How frequently can the species in the photograph be identified?
We asked this question of seven of the taxa in the Virtual Museum (http://vmus.adu.org.za). We looked at scorpions, lacewings, birds, frogs, reptiles, butterflies, and dragonflies and damselflies.
What happens is this. Citizen scientists upload their photographs into the Virtual Museum. A record can consist of one to three photographs. The second and third photographs are usually used to show different angles on the animal. They will know that the record is butterfly, and that it ought to be submitted to LepiMAP, and that the scorpions go to ScorpionMAP, etc. But they don’t need to know what species they are uploading (although they can submit their identification, or even tentative identification). For each of these groups of species, there is an expert panel consisting of specialists, often citizen scientists themselves. These experts do their best to make an identification to species (or even subspecies level for some butterflies and reptiles). But they are careful, and if the identification cannot be made with certainty to species level, they allocate a genus, and sometimes even a family. This mostly happens when the photo is a bit blurred, or if the critical ID feature is not shown. And some species can only be identified when the species is captured, and the critical diagnostic features, often the genitals, are examined with a magnifying glass! The identifications are displayed for all to see and examine on the Virtual Museum website; as a result, the members of the expert panels tend to err on the side of caution.
Let’s work our way through the seven groups. For each group of species, we will count the number of records submitted, and calculate the percentage which have been identified to species level. Each group is illustrated with a recently uploaded record from the Virtual Museum.
This is Opistophthalmus gigas. At this stage the scorpions only have scientific names. There is a great need to make them more accessible to everyone by allocating English common names! The photograph was taken by Luke Kemp in Namibia. The ScorpionMAP details are available at http://vmus.adu.org.za/?vm=ScorpionMAP-3490
Scorpions. We expected the scorpions to be tricky. But of the first 3,259 scorpions to be submitted to ScorpionMAP, 3,259 have been identified to species. That is an incredible 98.6%.
This is one of the “green lacewings”. It is identified to family Chrysopidae. To see more detail, go to LacewingMAP and look at http://vmus.adu.org.za/?vm=LacewingMAP-15501. This photograph was uploaded from Swaziland by Kate Braun. Mervyn Mansell comments: “Unfortunately it is not possible to identify any closer. It is quite difficult to distinguish between the various green lacewing species without a close examination of the wing venation and the male genitalia. The females of the different species are difficult to separate even if wing venation is clear. Some species are, however, characteristic and can be distinguished from photos, This is is possibly one of the members of the genus Chrysoperla“
Lacewings. We knew the lacewings would be really really difficult. For the “green lacewings”, the Chrysopidae, many species need to be dissected to identify them! In spite of the problems, Mervyn Mansell, the lacewing specialist, has identified 1,556 of the 2,380 records uploaded to LacewingMAP to species. That is a commendable 65.4%. Even for the green lacewings, the ID-to-species rate is 35%. That is far higher than Mervyn anticipated when LacewingMAP started.
The beautiful Common Moorhen was photographed today, 2 November 2018, and the photo immediately uploaded by Adriette Benade from near Alexander Bay in the Northern Cape, South Africa. The BirdPix record is permanently curated at http://vmus.adu.org.za/?vm=BirdPix-63485
Birds. 61,657 bird records have been submitted to BirdPix. 61,518 have been identified to species. That is 99.8%. That is the highest rate of all. BirdPix has the potential to make a huge contribution to the African Bird Atlas. Wherever you are in Africa, take photos of birds and upload them. The chances of the species being identified are overwhelming!
Frogs. The frogs are potentially difficult to identify from photographs. Sometimes the key ID features can only be seen if there is a series of photos from different angles. The number of records submitted is 8,221, of which 7,898 have been identified to species. That is 96.1%. Given the difficulties, that is remarkably high.
Reptiles. The number of sets of reptile photos uploaded to ReptileMAP is 19,980. Many species of reptile are cryptic, and identification involves counting scales, etc. So it is not self-evident that the rate of identification from photos will be large. But the success rate in the Virtual Museum is an astonishing 98.8%. 19,736 of the records have been have identified to species or subspecies level.
Ryan Tippett uploaded this exquisite Eastern Sorrel Copper. He took the photo in the Clocolan District of the Free State. It was the fourth record of this species from this grid cell. That sounds pretty boring. Until you grasp that it “refreshed” the most recent previous record, made in December 1995. That’s 23 years ago. Refreshing old records is incredibly important, because it provides evidence that a species still occurs at a site. Details of this record are at http://vmus.adu.org.za/?vm=LepiMAP-661549
Butterflies. The butterflies constitute the largest component of the Virtual Museum. There are 88,892 sets of up to three photographs. 95.3% have been identified to species or sub-species level. There are six families of butterflies, and four are unproblematic! 88% of the butterflies identified to family or genus level come from two families: the Lycaenidae (the blues and the coppers) and the Hesperiidae (the skippers). These are the two tricky families with lots of lookalike species.
Citizen Scientist Alan Manson has made a massive contribution to OdonataMAP, especially from KwaZulu-Natal. Once upon a time, he was a birder, but then he saw the light, and got hooked on the dragonflies and damselflies. He took this photograph of a Violet Dropwing near Komatipoort in Mpumalanga. Full details are at http:// http://vmus.adu.org.za/?vm=OdonataMAP-58739
Dragonflies and Damselflies (the Odonata). The OdonataMAP database is growing fast. It now consists of 56,039 records. This is another tricky group, in which identification depends on subtle features. In spite of this, the expert panel has identified 51,291 records to species level. That’s an amazing 91.5%.
Take home message. 95.6% success rate in identifying to species!
The take home message. The question we asked at the start was “How frequently can the species in the photograph be identified?” Across the seven groups of species considered here, a total of 240,428 records have been submitted to the Virtual Museum. That is almost a quarter of a million records. Of these, 229,927 have been identified by one of the expert panels to species (or subspecies) level. That is an impressive 95.6%. For six of the seven groups, the identification-to-species rate exceeds 90%. The lacewings get dragged down by the “green lacewings”. The take home message has to be that the value of photographic records to biodiversity mapping at the species level, as done by the Virtual Museum, is massive.
BDI took occupation of its unit in Epping Industria I on Monday this past week. Director Pete Laver is doing some spectacular innovations. Watch this space.
Meanwhile we are exploring our new neighbourhood. It’s a mix of industrial warehouses and factories. Lots of hard surfaces: roads, roofs and paving. But the sheer number of birds is impressive.
The most common species is House Sparrow. This is the male of a pair with a nest behind the fire alarm. What happens when the alarm goes off?House Sparrows everywhere. This rust inspector is on the job.Most razor wire never actually gets to serve its function of keeping intruders out. Here is an alternative use for razor wire. Providing this House Sparrow with a perch in the early morning sun. Although Factory Sparrows (sorry, House Sparrows) are abundant, they do not manage to totally exclude Cape Sparrows.Rock Doves (feral pigeons) are also almost ubiquitous. This concentration must be finding something special on the stones! You need to remove the speck of dirt from your beautiful sheen.A comfortable spot for a preen.The Rock Doves share this space with three other members of the pigeon-dove family. This industrial Laughing Dove is closing its eyes while the southeaster ruffles its feathers.The Red-eyed Dove has found a daytime use for street-lighting. There IS a little bit of green in this picture. This Speckled Pigeon was finding food on the tar.The third most abundant species is, like the House Sparrow and Feral Pigeon, an alien. The only green in this picture is the sheen on wing of the Common Starling. There’s an indigenous starling too. This Red-winged Starling has found a little snack.
Even in this environment there are people who care for their biodiversity. People, who in their own way, are “connected to nature.” Here are three containers of water. They have rocks in them so that the birds can perch and drink (and so that the southeaster doesn’t blow them away).Epping Industria I, established in the 1940s, is what is known as a novel ecosystem. A space so utterly transformed that it cannot serve any conservation function. Is that really true? If the biodiversity can be used to “connect to nature” the thousands of people who work here, then it can serve a purpose. We live in the “Anthropocene”, the period in which human activity is the dominant influence on the environment and on biodiversity. Ultimately, the only way we are going to achieve biodiversity conservation is by ranking up the concept of “connectedness to nature.” And BDI will try, in its way, to achieve this in Epping Industria I.Here are two species in Epping which don’t have to compete with alien “cousins.” This Cape Wagtail is hiding in the shadow of a security fence ….. and this, with its grey collar, is a Cape Canary … By the time we get to write Industrial Biodiversity 2, the BDI logo will be in the frame above the door of Unit 4.
Dragons do exist, and they’ve been around for over 300 million years! They might not breathe fire, but they do have six legs, four wings, and extremely keen eyesight. These mini dragons are carnivorous insects known as dragonflies (Anisoptera) and damselflies (Zygoptera), belonging to the insect Order Odonata. OdonataMAP, the Atlas of African Odonata, funded by the JRS Biodiversity Foundation is a project in the Animal Demography Unit’s Virtual Museum aiming to: (1) map the current distribution of the dragonflies and damselflies occurring in Africa; and (2) to serve as a repository of all existing distribution data for this group in the geographic extent of the project so that we can better understand their conservation priorities.
The first Shoot the Dragons Week for the 2018 Spring/Summer season kicked off on 22 September 2018. OdonataMAPpers were out and about, armed with their cameras, smiles and enthusiasm, to see how many dragonflies and damselflies they could snap and map. These beautiful insects are important monitors of water quality. They are sensitive to environmental change and play key roles in both terrestrial and aquatic habitats. They are predators as both nymphs and adults, feeding on a variety of prey including nuisance species such as mosquitoes and biting flies. Spending most of their lives underwater in rivers, streams, ponds, and lakes, their presence in aquatic environments is an excellent measure of water quality as they require clean water to thrive.
For the Week (which ran from 22 to 30 September 2018) a total 724 dragons were snapped, mapped and uploaded to the OdonataMAP database at http://vmus.adu.org.za. Records came in from Botswana, Kenya, Namibia, South Africa, Zambia and Zimbabwe! For South Africa, most of the records came from KwaZulu-Natal Province (173).
Diana Russell mapped the most dragons for the Shoot the Dragons Week with 80 records, followed by Norman Barrett (76) and Richard Johnstone (41). This is amazing! A massive thank you also goes to each and everyone that contributed records during the week. Every single record counts. Of the 724 records that were submitted (which covers 73 different taxa), 78,5% have been identified already, thanks to the super OdonataMAP expert panel.
The dragon that was snapped and mapped most commonly during the Week was the Red-veined Darter Sympetrum fonscolombii, with 81 records, followed by the Tropical Bluetail Ischnura senegalensis (52) and Black Percher Diplacodes lefebvrii (34). There were 15 species for which more than 10 records were submitted during the Shoot the Dragons Week.
Bernardine Altenroxel has recently graduated cum laude with a BSc(Hons) in Geography from the University of South Africa (UNISA). So, with her studies behind her for the time being, BDI sent her a new assignment, with a series of questions relating to citizen science. Bernie has contributed more than 4,000 records to the Virtual Museum; insects are her main interest with 3,000 contributions to LepiMAP and 500 to OdonataMAP.
Degrees from UNISA are underpinned by great feats of determination and persistence. Congratulations to citizen scientist Bernadine Altenroxel on the award of a BSc(Hons) in May this year
Bernardine Altenroxel does “disaster management”, the business of turning chaos into order. She says: “If there is anything my line of work has taught me, it is to never take a single day for granted. Any given day has the potential to descend into utter chaos – from accidents, to fires, to floods. If disaster management has taught me about bringing order back from disorder, biomapping has taught me about the need for balance and harmony in the natural environment. One speaks to the other, for without balance and harmony in the natural environment, disorder will inevitably follow; within disorder, balance and harmony need to be restored.”
BDI: Bernie, how did you become a citizen scientist? What was the catalyst that got you going?
In 2009, I had been going through a really rough time and felt the need to get away on my own for a few hours to clear my head. Lekgalameetse Nature Reserve was, and remains, one of my favourite places and this seemed like the ideal place for me to gain clarity on what I should do with my life. There had been profound and abrupt changes in my life which I needed to grasp, and the tranquillity of Lekgalameetse was sure to help me think clearly … plus provide me with the opportunity to test out my recently bought digital SLR camera. On a bright mid-winters day in 2009, I entered Lekgalameetse and to my absolute delight found the solitude I so craved. Besides the Reserve staff, there was not another person that I encountered whilst there. Little did I know it then, but this day would serve as a catalyst which would see me embark on exciting journey of learning and discovery, and entry into the exciting world of citizen science.
The Malta Waterfall at Lekgalameetse Nature Reserve where my journey into the world of citizen science originated.
As I sat beside the Malta Waterfall, deep in thought, a butterfly lazily drifting around in a shaft of sunlight caught my attention. It was unlike any butterfly I could recall having seen before, and I couldn’t help but watch as it landed on a nearby leaf. Barely breathing, I carefully stood up and tried to take a photograph, but the butterfly lifted off the leaf and started to circle again. Dejected at the missed opportunity, I sat down again, but could not help watching as the butterfly fluttered around and then settled on the end of the same leaf again. Eventually I managed to take a photograph of the butterfly. Little did I know that this would be the first of many happy hours spent photographing butterflies. For many months I puzzled over the identity of the butterfly. I just couldn’t get it off my mind. Internet searches yielded nothing and back then I had no books to use as a reference. This single record would eventually serve as the catalyst which would see me drawn into the world of citizen science. The curiosity over the butterfly would just not go away. Eventually, I submitted the record to a citizen science project and finally found the answer I had been looking for. The butterfly was a common mother-of-pearl butterfly. More butterfly records soon followed.
One of the decisions I had taken back in 2009, as I sat beside the Malta Waterfall, was to study further. Having enrolled with UNISA in 2011 for an environmental management degree, I centred my Ecotourism module project (undertaken in 2014) around the butterflies of Lekgalameetse. While researching the project and searching for data on the butterflies of Lekgalameetse, I came into contact with Megan Loftie-Eaton and Professor Les Underhill. They helped me with the information I required, and invited me to become a contributor towards the Animal Demography Unit’s Virtual Museum. It was under their guidance and constant encouragement that I would see myself fully immersed in the world of citizen science, coming into contact with other people who shared my enthusiasm. Pretty soon, I was noticing more than just the butterflies and started to submit records for more of the Virtual Museum projects. This chance encounter with Megan and Les has led me on a path of discovery which has not only shaped my private life and academic progression (I now hold a Batchelor’s degree in Environmental Management and a BSc Honours degree in Geography), but has also contributed significantly towards my work within disaster management. My whole life has been turned around since 2009. Citizen science has literally helped me to heal and grow.
The butterfly which first drew me into citizen science. It is a mother-of-pearl (Protogoniomorpha parhassus) one of the common butterflies of the region.
BDI: What has been the highlight for you?
The absolute highlight was, quite accidentally, re-discovering the Zimbabwe yellow-banded sapphire butterfly (Iolaus nasisii) in 2015, and subsequently being able to locate and successfully rear the Iolaus nasisii caterpillar. I also stumbled upon a thriving community of cryptic spreadwings (Lestes dissimulans) in an area where they have not previously been observed. There can be no better feeling than being able to contribute towards the scientific understanding of species’ distribution and ultimate conservation.
The newly emerged Zimbabwe yellow-banded sapphire butterfly (Iolaus nasisii). While carrying a bundle of hay for my horse on 12 November 2015, I found a small, colourful butterfly. The butterfly was unfortunately dead, probably having succumbed to one of the heatwaves to have gripped Limpopo during October and November. Being a keen LepiMAPper, and instantly recognising the butterfly as an important find, I scooped it up with my free hand, fed my horse and headed back indoors. (http://vmus.adu.org.za/?vm=LepiMAP-582581)
BDI: How has being a citizen scientist changed your view of the world?
Besides bringing me through a difficult period in my life, citizen science has provided me with a deeper understanding of how different components within the environment come together to make an ecosystem whole and functional, and how easily human activities can totally mess this up. This is something I continuously consider in my work within disaster management.
BDI: What are you still hoping to achieve?
Looking ahead, I am hoping for the opportunity to explore more areas and further contribute towards our understanding of the distribution of different species and how this is changing, especially in the face of climate change. My camera is nearly always part of my baggage. I am often required to travel around for work, and will take my camera with me if I think there may be an opportunity to obtain a few more records. This has delivered some surprises, like finding a Lucia Widow at a temporary pool of water in Giyani or a beautiful Streamer Tail moth in Tzaneen (see below). Just by chance, I was talking on my cellphone outside our offices in Tzaneen when the Streamer Tailed moth fluttered by. In a few slick, ninja-like moves, I managed to catch the moth, take a few photographs and release it again – much to the amusement of my work colleagues. I have yet to find another of these gorgeous moths. It is elusive species such as this which I hope to still encounter on my journey.
The Streamer tail moth caught outside my place of work in Tzaneen.
I try to reach 1000 records per year for the Virtual Museum. This is the first year that I have struggled to reach this target. This is largely due to the sudden drop in Lepidoptera numbers, a phenomenon observed across most parts of South Africa, in the summer of 2017/18..
BDI: How do you react to the statement that “Being a citizen scientist is good for my health, both physical and mental!”?
Citizen science really inspires a person to get out there and explore the environment – thus pursuing healthy activities. Within my line of work, one unfortunately often has to deal a lot with the darker side of life. In my spare time, spending time in the environment looking for new records which can contribute towards citizen science projects, and the excitement of finding something new, really helps me to unwind and de-stress. This helps me to cope in what can be a very hectic, demanding environment.
“Disaster management” is the business of turning chaos into order. There are no dull moments! Something is always demanding attention. Citizen science helps me to unwind and de-stress after a hectic week or event.
What do you see as the role which citizen science plays in biodiversity conservation? What is the link?
There is most certainly a link between citizen science and the conservation of biodiversity. Without the knowledge which is being generated by citizen science, I think it would be far more difficult to really monitor biodiversity. At the same time, there is a great deal of awareness which is being raised which contributes towards conservation and the promotion of biodiversity. In a rapidly changing world under climate change, the massive number of records generated through citizen science can broaden our understanding of how the distribution of different species is changing, and ultimately how this may impact on the human environment as well. We cannot live on this planet and think we are in no way connected with the natural environment. We depend on the environment, and if the environment suffers, so do we. Citizen science can make significant contributions by reaching a broad range of people, who in turn inspire and teach others this very basic concept.
Systematic atlasing in Hessequa – moving from mapping to monitoring
Johan A van Rooyen*
U3A Stilbaai – Bird Group
Introduction
Les Underhill and Michael Brooks in their 2016 paper about the progress of the Second Southern Africa Bird Atlas Project (SABAP2), mention the Stilbaai Bird Club in the paragraph “Personal, club and group challenges and targets”. In this paper, I document the targets set and achieved by the atlasers of the Stilbaai Bird Group over the period 1 October 2014 to 30 November 2017 (Underhill & BrooKs 2016).
In September 2014, the Stilbaai Bird Club was introduced to the SABAP2 protocol (fully described in Underhill 2016). Some members started atlasing in October 2014. The atlasing of the Stilbaai atlasers is coordinated by the author of this paper. In 2016 the bird club was integrated into the U3A: Stilbaai as a Bird Group.
The Stilbaai atlasers started off as a group of 10 atlasers of which eight are husband and wife teams and in 2017 they were joined by two more atlasers. All of them are retired and live in Stilbaai, except for one couple who reside in George.
Because Stilbaai falls in the Hessequa Municipality, it was decided to atlas the pentads that cover the municipal area. The area is shown in Figure 1 and lies more or less between the Breede River in the west and the Gouritz River in the east, and the Langeberg Mountain in the north and the ocean in the south. A few pentads without access roads in the Langeberg Mountain were excluded, as well as two pentads in the south on private land where access could not be arranged. The resultant “Hessequa Atlas Area” comprises 75 pentads. For ease of reference the pentads were all given names of farms or towns or other prominent features over and above the standard reference number and those names are used by all the atlasers in the group.
Fig 1. Map of Hessequa atlas area
This is a large area of about 110 x 55 km with the farthest pentads between 90 and 100 km from Stilbaai. This area forms the eastern half of the Overberg and is almost entirely rural. Most of the area is agricultural, where the main crop is wheat. In the south, much of the coastal fringe is natural vegetation. The northern pentads lie along the Langeberg mountain range.
The objectives set by the group for each of the years evolved over time, but it was realised right from the outset that it must accommodate the two broad objectives of SABAP2. That is to improve the information for mapping purposes, as well as to move towards monitoring as a longer term goal. The objectives and achievements for each year are given in more detail in the rest of the paper.
It is important to realise that it is not only the Stilbaai atlasers who are doing SABAP2 fieldwork in this area. The coastal towns of Witsand, Stilbaai/Jongensfontein and Gouritsmond are popular holiday destinations and have attracted a fair share of visiting atlasers. The same applies to the Grootvadersbosch Nature Reserve and the very popular Voëlvlei near Gouritsmond. A number of visiting atlasers also contributed significantly in the rest of the area.
Coordination of atlasing in Hessequa
Atlasing systematically in Hessequa is coordinated by using a semi-automated spreadsheet system that incorporates the specific targets for any given year. The Stilbaai atlasers are issued with a priority list of pentads by email at the start of each month from which each atlaser then chooses the pentads they want to visit. Each atlaser informs the others of his/her choice by using “reply to all” to prevent duplication. The list is also updated weekly to show the choices already made and pentads completed.
The spreadsheet is updated regularly by keeping track of atlas cards that are submitted for the Hessequa area. A “Pentad Group” covering the Hessequa area was created on the SABAP2 website (Figure 2) and this shows information only for the 75 pentads. This simplifies the monitoring of submitted cards tremendously. Many cards are submitted by visitors to the area and this is the most efficient way of keeping track of those cards as well. The information from the website is copied to the spreadsheet to mirror the website and allows for calculations to compare cards submitted to the targets that were set.
Fig 2. Hessequa pentad group on SABAP2 website
Base conditions
In the remainder of this paper the pentads of the Hessequa atlas area are shown schematically and the number of completed full protocol cards for each pentad is shown in the same colours as on the SABAP2 website. The legend is given in Figure 3 for easy reference.
Fig 3. Legend indicating number of full protocol cards per pentad
In each cell in the following figures the top line is the pentad number, the second line the Stilbaai atlasers’ name for the pentad and the third line the number of full protocol cards.
The cumulative coverage of the Hessequa area from the start of SABAP2 in July 2007 up to the end of September 2014 is shown in Figure 4. At the start of this initiative, only 15 of the 75 pentads had one full protocol card and 27 pentads had reached the foundational coverage of four or more cards (Figure 4).
Fig 4. Cumulative full protocol cards up to 30 September 2014, at the start of systematic atlas fieldwork in the Hessequa
Atlasing in 2015
The Stilbaai atlasers started slowly in the last quarter of 2014 but firm targets were set annually from the beginning of 2015.
The first target for 2015 was to increase the coverage for mapping purposes and the specific aim was to turn Hessequa green, that is a minimum of four cards per pentad. It was, however, also agreed by the atlasers that more than that could be achieved and two quarter degree squares, one around Stilbaai (3421AD) and the one just north of it (3421AB) were selected for more intense atlasing. This area is called the Stilbaai core area and the aim was to turn it dark green with seven cards per pentad.
The second target for 2015 was already focusing on the monitoring objective of SABAP2 and it was decided that each pentad will be atlased at least once regardless of the number of cards already submitted.
The 2015 coverage that was achieved is shown in Figure 5. A total of 195 full protocol cards were submitted, 152 by the Stilbaai atlasers and 43 by visitors. The monitoring target of a minimum of one card per pentad was thus achieved. The cumulative coverage by 31 December 2015 is given in Figure 6.
Fig 5. Full protocol cards submitted during 2015, the first year of systematic atlas fieldwork in the HessequaFig 6. Cumulative full protocol cards up to 31 December 2015 at the end of the first year of systematic atlas fieldwork in the Hessequa
The target of “turning Hessequa green” was, except for three pentads, achieved by the end of 2015 and the coverage of the Stilbaai core area was increased to seven cards or better (Figure 6).
Atlasing in 2016
The monitoring target was set slightly higher for 2016 to a minimum of one card per pentad for the whole area, except for the Stilbaai core area where it was set as a minimum of 4 cards. It was also decided to atlas the two home pentads around Stilbaai (3420_2120 and 3420_2125) at least once a month.
The mapping target was to get the Stilbaai core area to 11 cards (light blue). A longer term mapping target was to get the rest of Hessequa to a minimum of 7 cards (dark green) by the end of 2017. In order to spread the work load between 2016 and 2017 some pentads would then have to be atlased twice during 2016.
During 2015 no attention was paid to ensure an equal distribution of cards over the months of the year for each pentad. For 2016 and subsequent years, it was decided to aim for as equal a distribution as practically possible and pentads were prioritised on a monthly basis to achieve this target. The result of what was achieved to 30 November 2017 is discussed later on.
The 2016 coverage is shown in Figure 7. A total of 277 full protocol cards were submitted, 175 by Stilbaai atlasers and 102 by visitors.
The monitoring targets were met except for pentad 3355_2050. During a data quality control exercise during 2017 it was found that a number of cards that were submitted as full protocol cards did not cover the required minimum of two hours atlasing. They were subsequently changed to ad hoc cards and the one full protocol card that was submitted for 3355_2050 for 2016 was changed to an ad hoc card. Quality control is now done on a continuous basis in order to prevent this from occurring again.
The cards submitted for pentads 3420_2120 and 3415_2120 were much higher than expected due to the out-of-range Red-necked Buzzard that caused a huge influx of “twitchers” who also submitted full protocol cards. But as Underhill & Brooks (2016) stated: “There is no pentad for which SABAP2 has”enough” checklists.”
The cumulative coverage by 31 December 2016 is given in Figure 8. All pentads had by this stage reached the minimum mapping requirement of 4 cards, the Stilbaai core area the 11 card target and some of the others had by now reached the 7 card (dark green) stage.
Fig 7. Full protocol cards submitted during 2016, the second year of systematic atlas fieldwork in the HessequaFig 8. Cumulative full protocol cards up to 31 December 2016, at the end of the second year of systematic atlas fieldwork in the Hessequa
Atlasing in 2017
After a discussion with Prof Les Underhill late in 2016, it was decided to increase the monitoring target for Hessequa. The target for 2017 was set for a minimum of two full protocol cards per pentad for the whole area.
This target was already achieved by 30 November 2017 and is shown in Figure 9. A total of 267 full protocol cards was submitted, 212 by Stilbaai atlasers and 55 by visitors.
Fig 9. Full protocol cards submitted during 2017, the third year of systematic atlas fieldwork in the Hessequa
The cumulative coverage up to 30 November 2017 is shown in Figure 10 and the whole of Hessequa was by this date dark green (seven or more cards).
Fig 10. Cumulative full protocol cards up to 30 November 2017, at the end of the third year of systematic atlas fieldwork in the Hessequa
Targets for 2018
In further communication with Prof Les Underhill during 2017, it was recommended that an even more ambitious monitoring target be set for 2018. That is to again do two full protocol cards per pentad, but to distribute these cards evenly over the four seasons of the year.
The four seasons are defined as follows:
Summer – December, January and February
Autumn – March, April and May
Winter – June, July and August
Spring – September, October and November.
It is this definition that forced the “shortening” of the 2017 atlas year to end by 30 November in order to start with the new programme on 1 December 2018.
The Stilbaai atlasers, however, decided to increase the 2018 target by aiming to do four cards per pentad (one card per season) for the Stilbaai core area. The two home pentads will again be atlased at least once per month.
The target for 2018 is shown schematically in Figure 11. In this figure each pentad has four rows, one for each season starting with summer at the top.
Fig 11. Atlas targets in the Hessequa for 2018, showing planned seasonal distribution of effort
Figure 11 shows that the 2018 target for the Stilbaai core area is a card in every season and three cards per season for the Stilbaai home pentads (continuing with the one card per month objective). In the rest of Hessequa the target is for each pentad to get a card for summer and winter while the adjacent pentads will get cards for autumn and spring in a chessboard pattern. If this is achieved, the pentads will be switched around in 2019 to cover all four seasons in a two year cycle. Two exceptions to this rule can be seen in the northeastern and northwestern corners of Hessequa where access problems make it a logistical imperative for two adjacent pentads be done at the same time.
If the above targets are achieved, the Stilbaai core area will be turned dark blue (16 cards) during 2018 and the rest of the Hessequa area light blue (11 cards) which will provide excellent information for the objective of mapping bird distributions.
Monthly distribution of full protocol cards
Since the start of 2016 the Stilbaai atlasers have aimed to spread the atlas cards as evenly as practically possible over the months of the year. The monthly distribution of the cards as on 30 November 2017 is shown in tabular form in Figures 12, 13 and 14. The colours used in the monthly columns are the standard colours used throughout this paper.
Fig 12. Monthly distribution of cards in the Hessequa achieved up to 30 November 2017 (Pentads 1-25)Fig 13. Monthly distribution of cards in the Hessequa achieved up to 30 November 2017 (Pentads 26-50)Fig 14. Monthly distribution of cards in the Hessequa achieved up to 30 November 2017 (Pentads 61-75)
It can be seen from Figure 12, 13 and 14 that the distribution of the cards over the months of the year is very good, except for the pentads where a large number of cards have been done by visitors. That is perfectly understandable as they often visit the area during the same time of the year and those cards obviously contribute greatly towards the detailed understanding of species distribution during those months.
Conclusions
From 1 October 2014 to 30 November 2017, the Stilbaai atlasers, with a steady stream of cards from visitors, improved the foundational coverage of the Hessequa area. Initially 20% of pentads had one card and about a third of pentads had four cards (Figure 4). At the end of this period, the coverage depth was seven cards or more for every one of the 75 pentads of the Hessequa area and 11 or more cards for the Stilbaai core area.
This was achieved while simultaneously achieving monitoring targets of at least one card per pentad for 2015 and 2016 and two cards per pentad for 2017. An excellent distribution of full protocol cards over the months of the year was also achieved. This will be taken forward into the future.
With the foundational coverage on a sound footing, the Stilbaai atlasers will focus on more intensive monitoring in future and will strive for an even distribution of full protocol cards over the seasons of each year. This paper describes a good example of what can be achieved by a group of birders working together with a systematic strategy towards atlasing goals.
Acknowledgements
We are greatly indebted to the 146 visiting atlasers who built the base from 2007 to 2014 and who are still contributing large numbers of cards every year. The following atlasers contributed 10 or more cards to the Hessequa area and deserve a special mention: Pieter de Waal La Grange (73), Don Reid (34), Josef van Wyngaard (20), Pat Nurse (19), Brian Vanderwalt (18), Stefan Theron (17), John Carter (16), Tineke Malan (16), Garth Shaw (16), Adrius Rabie (14), Alan Collett (10), Maria Kemp (10) and Hans Jurie Linde (10).
The Stilbaai atlasers are a special group of people who took to atlasing with great enthusiasm and have been willing to do their atlasing in a coordinated way since October 2014. Without their unwavering support, this would not have been possible. They are Patrick and Alice Duddy, Ben and Joekie Jovner, Phil and Esther Scheffer, Hennie and Gerda Smit, Menno Stenvert and Krysia Solman, Terry and Maria Terblanche, Annelie van Lill, Johan and Estelle van Rooyen, Rita van Rooyen, John and Jeannie Willemse, Dirk Bosman and Derick Oosthuizen.
References
Underhill LG 2016. The fundamentals of the SABAP2 protocol. Biodiversity Observations 7.42:1-12.
Underhill LG, Brooks M 2016. SABAP2 after nine years, mid 2007-mid 2016: coverage progress and priorities for the Second Southern African Bird Atlas Project. Biodiversity Observations 7.37:1-17
Common starling Sturnus vulgaris expansion in South Africa
Ielyzaveta M Ivanova
School of Animal, Plant and Environmental Sciences, University of the Witwatersrand, Private Bag 3, Wits 2050, South Africa
Craig T Symes
School of Animal, Plant and Environmental Sciences, University of the Witwatersrand, Private Bag 3, Wits 2050, South Africa
The Common Starling Sturnus vulgaris is a medium-sized granivorous and frugivorous bird (Craig 2005), with a native range across large parts of Europe and western Asia. It was introduced to Cape Town in 1899, colonising the Cape region during the early 20th century (Winterbottom & Liversidge 1954). Since then, the species has continued to systematically extend its range into South Africa (Craig 2005). Using the available data in SABAP2, collected over the last 10 years (July 2007 – June 2017), we present a summary of the progressive expansion of the species in South Africa.
The presence of the Common Starling is reported in more pentads (5’X5’ geographical grids used in SABAP2) in the 2016/17 period (736 pentads) than in 2007/08 (383 pentads) (Table 1), demonstrating a significant increase in distribution over the past 10 years. The species range appears to be in a state of continuous expansion as it spreads from the original source of introduction, as shown by the large numbers of previously unoccupied pentads reporting the Starling over time (Figure 1, Table 1). Despite this, the actual number of pentads reporting the Starling in any given period is relatively stable, perhaps even declining slightly (Table 1). The overall proportion of pentads reporting the Starling shows a steady decline over the period, which would likely be attributed to increases in the overall SABAP sampling effort (of Starling absent pentads) outpacing the species range expansion. Across its range, the Common Starling appears to have a relatively consistent abundance over time (as represented by the Starling’s reporting rate, Table 1).
Fig 1. Reporting rates of the Common Starling across pentads (5’X5’ geographical grids) in South Africa, in July 2007 – June 2008 (A) and July 2016 – June 2017 (B). Different colours denote reporting rates, presented as percentage of all record cards completed in each given pentad.
Table 1: Range expansion and abundance of the Common Starling in South Africa, for July-June annual periods in 10 years of SABAP2 sampling (July 2007 – June 2017).
Year perioda
Pentadsb
Newc
Reporting rated
2007/08
383 (19.8)
383
50 ± 45
2008/09
677 (15.9)
423
52 ± 45
2009/10
864 (16.6)
334
52 ± 43
2010/11
865 (15.9)
251
53 ± 44
2011/12
843 (15.6)
191
52 ± 43
2012/13
759 (14.8)
124
51 ± 44
2013/14
636 (12.2)
83
47 ± 44
2014/15
659 (12.0)
82
48 ± 44
2015/16
804 (13.4)
106
46 ± 43
2016/17
736 (12.2)
72
45 ± 43
a(July – June) bbNumber of pentads with Starlings (as % of sampled pentads) cNumber of new pentads with Starlings dReporting rate across Starling-reporting pentads (mean % ± SD)
The slight declines in the species range and abundance over the 10 years indicate that the presence of the species in an area does not necessarily result in long-term persistence. A similar decline is observed for the Starling in the United States, following a very rapid period of initial colonisation (Sauer et al. 2008). The expansion of the Starling’s range appears to be mitigated numerically by its contraction elsewhere in the country. As such, the colonising behaviour of the Common Starling in South Africa appears to be one of venturing into new territory, with a lag period of decline in less suitable areas where it may not be able to persist. A possible explanation of the high expansion rate is the general tendency to move along pathways of lower resistance, such as lower elevation terrain that is preferably under cropland or pasture (with the contrary causing a greatly slowed expansion, such as in the Iberian Peninsula, Ferrer et al. 1991).
Common Starling in Gauteng
In Gauteng, the Common Starling first made an appearance in 1986 (Boucher 2018), but consistent reporting of the species in the region did not begin until the early 21st century. A recent arrival, the Starling is already making steady range gains, being reported in “new” Gauteng pentads in each data period (Table 2). With the increasing number of pentads reporting the Starling, the average reporting rate for the species across the province is showing an obvious rise (Table 2). Such an expansion pattern resembles the initial phases of the Starling’s colonisation of the country at large, as discussed previously – quick gains in range.
Table 2: Range expansion and abundance of Common Starling in Gauteng, for July-June annual periods in 10 years of SABAP2 sampling (July 2007 – June 2017).
Year perioda
Pentadsb
Newc
Reporting rated
2007/08
1 (0.5)
1
0.02 ± 0.30
2008/09
4 (1.5)
3
0.06 ± 0.50
2009/10
1 (0.4)
1
0.05 ± 0.86
2010/11
1 (0.4)
1
0.07 ± 1.20
2011/12
4 (1.5)
2
0.39 ± 3.82
2012/13
4 (1.6)
1
0.05 ± 0.48
2013/14
4 (1.4)
3
0.18 ± 1.69
2014/15
7 (2.5)
3
0.35 ± 2.68
2015/16
8 (2.9)
5
0.21 ± 1.96
2016/17
10 (3.7)
1
0.46 ± 3.19
a(July – June) bbNumber of pentads with Starlings (as % of sampled pentads) cNumber of new pentads with Starlings dReporting rate across all Gauteng pentads (mean % ± SD)
The reporting rate for the Starling across Gauteng as a whole averages only 0.18 % for the 10 years, reflecting the novel status that the species still holds in the province. The increase in Starling reporting rates is not statistically significant at this stage, despite their apparent growth (ANOVA single factor test; F(9,2647) = 1.627, p = 0.102). A likely explanation of this is the very high variability observed in the annual averages (Table 2).
From the growing reporting rates and increasing variability, it can be noted that the lag period of decline following rapid territory colonisation seen for the Common Starling in South Africa as a whole is not yet identified in Gauteng, but may follow on in the years to come.
Assessing a variety of land uses found in Gauteng, the Starling’s presence is consistently below 1 % throughout (when pentads are averaged by share of land-use type), not being reported at all in pentads with agriculture comprising over 60 % of land use (Table 3). This finding supports the attribution of the traditionally farmland-inhabiting Common Starling’s decline in Europe to the intensification of agricultural areas (Donald et al. 2001).
While sampling effort has increased over the years of the atlas, as awareness of and interest in the project grows, the range expansion of the Common Startling in Gauteng appears to not simply be a function of that effort – rather, we believe it reflects an actual increase in the number of pentads in which it occurs, which is supported by the growing percentage of sampled pentads reporting the species (Table 2).
General conclusions
In South Africa, the Common Starling appears to be following an expanding distribution pattern, as it spreads into new territory and establishes its presence. From the pattern of expansion, it is possible to speculate a future Starling distribution that spans the entire country and sub-region. Whether it is able to persist in more “unfavourable” regions (such as the dry Northern Cape Province) remains to be established. The species is expected to be most abundant in areas where agriculture is a prominent, but not dominant, land use (Table 3), indicating an avoidance for what is likely to be intensified farmland (cf. Donald et al. 2001).
Table 3: Reporting rate (%) for Common Starling in Gauteng within pentads containing different land-use types, averaged for all pentads of each type found in the province.
Land-use
Share of pentada
Reporting rateb
Agriculture
< 10
0.1
> 40
0.3
> 60
0.0
Natural
> 60
0.1
Settlement
> 60
0.3
Highly transformed
> 10
0.7
aShare of pentad occupied by land-use (%) b(%)
With regards to Gauteng, the future of the Common Starling is challenging to determine, as the observations are of a trend arguably in its initial phases. However, some extrapolations can be made. The open grassland of pre-settlement Gauteng would have been prohibitive to Common Starling colonisation, but the conditions for colonisation have since changed. Its diet of insects and fruits is well-suited to the now-afforested expanses of Gauteng cities (Schäffler & Swilling 2012), as is its preference of cavities for nesting. If its preference for areas with intermediate levels of agriculture, settlement, and land transformation persist, the species will continue increasing in both range and abundance across the province (which features a large proportion of relatively densely settled and transformed spaces). Therefore, it is likely that the species increase in Gauteng will become significant over time.
The Common Starling has been described as having the potential to disrupt natural processes such as seed dispersal (Richardson et al. 1996); however, not much work has been published on these impacts in the Cape region. The Starling is also thought to be able to displace cavity-nesting birds in southern Africa through nesting competition, as it does with the Olive Woodpecker Mesopicos griseocephalus (van der Merwe 1984). On the other hand, in the introduced range around New York City, there is little evidence to attribute a decline in cavity-nesting native species to competition with the Starling (Koenig 2003). Therefore, the impact of Starling on other bird species in Gauteng (many themselves occurring in increased abundance due to anthropogenic change) is difficult to predict. A further consideration is that alien birds are known to form positive as well as negative interactions with not only native birds, but also other “aliens” (Rosenzweig 2001; Orchan et al. 2013). This is important to note, as highly transformed environments such as Gauteng contain numerous “alien species” (Symes et al. 2017). As its distribution expands, the Starling may engage in competition for resources with other species in Gauteng, or it may expand to fill a vacant niche (a controversial concept in itself, Lekevicius 2009). If the Common Starling is to follow the footsteps of the Rose-ringed Parakeet Psittacula krameri, an alien species preceding it in Gauteng by a few decades, impacts on “indigenous” birds are predicted to be minimal to insignificant (Ivanova 2017). In attempting to quantify impact, and given that the species is a successful “invader” elsewhere in the world, we suggest that the Common Starling is one to closely monitor.
Public responses to exotic species are often emotive (Gozlan et al. 2013), and may lack credibility altogether when there is either little scientific evidence or when scientific evidence is ignored. From the trends found so far, it is clear that in the South African context much research is still needed to understand the complexities of changing bird communities in the face of rapid anthropogenic change. Indeed the clarification of numerous terms, and the context in which they are applied in this field of research, are frequently inconsistent and need attention (e.g. invasive and alien, as defined by Richardson et al. 2011). Furthermore, this topic needs informed public engagement to help prevent misinformation on complex ecological processes. A wealth of information in the form of citizen science SABAP data remains to be mined in helping understand these processes.
Acknowledgements
We would like to thank the large number of independent observers for their continued contribution to the SABAP2 database, whose work makes possible the project, and our use of it.
Craig AJFK 2005. Common starling Sturnus vulgaris. In: Hockey PAR, Dean WRJ, Ryan PG (eds). Roberts’ Birds of Southern Africa, 7th edition. The Trustees of the John Voelcker Bird Book Fund, Cape Town, South Africa: 971-972.
Donald PF, Green RE, Heath MF 2001. Agriculture intensification and the collapse of Europe’s farmland bird populations. Proceedings of the Royal Society of London B 268: 25-29.
Ferrer X, Motis A, Peris SJ 1991. Changes in the breeding range of starlings in the Iberian Peninsula during the last 30 years: competition as a limiting factor. Journal of Biogeography 18: 631-636.
Gozlan RE, Burnard D, Andreou D, Britton JR 2013. Understanding the Threats Posed by Non-Native Species: Public vs. Conservation Managers. PLoS ONE 8: e53200.
Ivanova IM 2017. Spatial and temporal impacts of the alien species Psittacula krameri on the occurrence of avifauna in Gauteng. Honours thesis, University of the Witwatersrand, Johannesburg.
Koenig WD 2003. European starlings and their effect on native cavity-nesting birds. Conservation Biology 17: 1134-1140.
Lekevicius E 2009. Vacant niches in nature, ecology, and evolutionary theory: a mini-review. Ekologija 55: 165-174.
Orchan Y, Chiron F, Shwartz A, Kark S 2013. The complex interaction network among multiple invasive bird species in a cavity-nesting community. Biological Invasions 15: 429-445.
Richardson DM, Pysek P, Carlton JT 2011. A compendium of essential concepts and terminology in invasion ecology. In: Richardson DM (ed). Fifty years of invasion ecology: The legacy of Charles Elton. Blackwell Publishing, Oxford, UK: 409-420.
Richardson DM, van Wilgen BW, Higgins SI, Trinder-Smith TH, Cowling RM, McKell DH 1996. Current and future threats to plant biodiversity on the Cape Peninsula, South Africa. Biodiversity and Conservation 5: 607-647.
Rosenzweig ML 2001. The four questions: what does the introduction of exotic species do to diversity? Evolutionary Ecology Research 3: 361-367.
Sauer JR, Hines JE, Fallon J 2008. The North American breeding bird survey, results and analysis 1966-2007. U.S. Geological Survey Patuxent Wildlife Research Centre, Laurel, Maryland.
Schäffler A, Swilling M 2012. Valuing green infrastructure in an urban environment under pressure – The Johannesburg case. Ecological Economics 86: 246-257.
Symes CT, Roller K, Howes C, Lockwood G, van Rensburg BJ 2017. Grassland to urban forest in 150 years: avifaunal response in an African metropolis. In: Murgui E, Hedbloom M (eds). Ecology and conservation of birds in urban environments. Springer International Publishing, Cham, Switzerland: 309-341.
Van der Merwe F 1984. ’n Nalatenskap van Rhodes: Europese Spreeus verdring Gryskopspegte. African Wildlife 38: 155-157.
Winterbottom JM, Liversidge R 1954. The European starling in the South West Cape. Ostrich 25: 89-96.
Geldenhuys L. 2018. Aggregations of African Black Oystercatchers in remote coastal areas of the Northern Cape Province, South Africa. Biodiversity Observations 9.8:1-5
Aggregations of African Black Oystercatchers in remote coastal areas of the Northern Cape Province, South Africa
Louise Geldenhuys
Northern Cape Department of Environment and Nature Conservation, Private Bag X16, Springbok, 8240
Abstract
Counts of African Black Oystercatchers along the Northern Cape Coastline, excluding the Namaqua National Park, were conducted during August and November of 2015, 2016 and 2017. An average of 387 oystercatchers were counted in this area. The area between Port Nolloth and Kleinsee accounted for 46 % of oystercatchers counted, and this relatively undisturbed and remote area could be an important site for the conservation of oystercatchers in South Africa.
Introduction
The African Black Oystercatcher Haematopus moquini is endemic to southern Africa, and breeds in the narrow coastal zone and on the offshore islands from southern Namibia to southern KwaZulu-Natal, South Africa (Hockey et al. 2003, Underhill 2014). Adults are monogamous and territorial, and will stay in their territory for life, but pre-breeding juveniles migrate between 150 and 2000 km during the first few years of their lives, after which they return to find a territory close to where they hatched. African Black Oystercatchers feed during low tide, and aggregate at specific roost sites during high tides (Figure 1). During the breeding season breeding birds do not join these roosts, and the aggregations of birds at roosts consists of juveniles and immature non-breeding birds. These aggregations of non-breeding birds usually feed in the vicinity of the roost (Rao et al. 2014).
The sites of these roosts stay more or less constant over years, and the conservation of these sites is important for the long-term survival of the species (Rao et al. 2014). The locations of these roost sites have previously been identified through aerial surveys of the coastline between Elands Bay in South Africa and the Kunene River at the border of Namibia and Angola (Rao et al. 2014). This paper presents more recent (2015-2017) observations of aggregations of African Black Oystercatchers in the Northern Cape Province.
The conservation status of the African Black Oystercatcher has recently been changed from Near Threatened to Least Concern, following an increase in numbers (BirdLife International 2017). This change in threat status can be attributed to an overall increase in population size; this, in turn, is attributed to a massive increase in food resources as a result of the invasion of the coastline by the Mediterranean Mussel Mytilus galloprovincialis, the sensitive management of the offshore islands along the South African and Namibian coastlines, and the exclusion of off-road vehicles from the coastline of South Africa (Underhill 2014).
Fig 1. A group of 39 African Black Oystercatchers between Port Nolloth and Kleinsee.
Northern Cape African Black Oystercatcher surveys: 2015 to 2017
African Black Oystercatcher numbers and locations were recorded during the annual Northern Cape coastal audits. Counts were conducted from 4×4 vehicles traveling as close to the coastline as possible. Counts were done throughout the day, and not exclusively during high tide. The area surveyed was divided into a northern and southern section (Figures 2 and 3), and each section was surveyed twice (northern section 2015 and 2017, and southern section 2015 and 2016). The area of the Namaqua National Park was excluded from these surveys.
In the northern section (Orange River Mouth to Kleinsee), totals of 290 and 364 oystercatchers were counted in 2015 and 2017 respectively. In the southern section (Western Cape boundary to Kleinsee), totals of 80 and 39 oystercatchers were counted in 2015 and 2016, respectively.
Fig 2. Oystercatcher counts in the northern section of the Northern Cape coastline in 2015 and 2017. Groups of ten or more are reflected by the orange circles (size correspond to group size). Large black circles indicates areas where groups were found in the same area in the different years.Fig 3. Oystercatcher counts in the southern section of the Northern Cape coastline in 2015 and 2016. Groups of ten or more are reflected by orange circles. There were no groups of ten or more observed in 2016.
For the entire Northern Cape coastline, excluding the Namaqua National Park, 370 oystercatchers were counted in the combined two sections in 2015, and 403 oystercatchers in the two sections in 2016 and 2017 combined. These totals are much greater than previously reported for oystercatchers between the Orange and Olifants Rivers as a total of 86 (1978-1980) and 79 (1997-2002) (Underhill 2014). It is not known if this difference is due to the differences in observation methods used, or if it is a reflection of an increase in oystercatcher numbers. It is more likely to be the latter; for example, on Robben Island, mean oystercatcher numbers increased from c. 120 in 2002 to 345 in 2012 to 516 in 2017 (Spiby 2012; Bukola Braimoh unpubl. observations).
Aggregation areas
In the northern section there were seven observations of groups of 10 or more oystercatchers in 2015, and 11 groups in 2017 (Figure 2). There were two groups of 10 or more oystercatchers in the southern section in 2015, and none in 2016 (Figure 3). Two of these aggregations occurred at the same place during both surveys (Figure 2), and these sites should be considered important for oystercatcher conservation. The area between Port Nolloth and Kleinsee appears to be an important area for aggregating oystercatchers, with an average of 46 % of the total number of oystercatcers in the Northern Cape (excluding Namaqua National Park) found in this area. This area is also currently relatively undisturbed. While access is restricted by De Beers, no active mining is currently taking place, unlike the areas between Alexander Bay and Port Nolloth, and between Kleinsee and the Spoeg River Mouth, where intensive coastal diamond mining is taking place.
Acknowledgements
Klaas van Zyl, Enrico Oosthuysen, Marnus Smit, Conrad Geldenhuys, Johan Jonk, Thinus Jonker, Adeleen Cloete, Bronwen Cornelissen, and Wilna Oppel assisted with oystercatcher spotting and counting. Alexcor, De Beers, and West Coast Resources granted access into mining areas. The Northern Cape Department of Environment and Nature Conservation funded this survey.
References
BirdLife International 2017. Haematopus moquini. [The IUCN Red List of Threatened Species 2017]. Available from http://www.iucnredlist.org/details/22693627/0, accessed on 25 January 2018.
Hockey PAR, Lesenberg A, Loewenthal D 2003. Dispersal and migration of juvenile African Black Oystercatchers Haematopus moquini. Ibis 145: E114-E123.
Rao AS, Hockey PAR, Montevecchi WA 2014. Coastal dispersal by pre-breeding African Black Oystercatchers Haematopus moquini. Marine Ornithology 42: 105-112.
Spiby J 2012. Trends in African Black Oystercatchers Haematopus moquini on Robben Island, South Africa: population size and nest characteristics. BSc(Hons) project, Department of Zoology, University of Cape Town.
Underhill LG 2014. Assessment of the conservation status of African Black Oystercatcher Haematopus moquini. International Water Studies 20:97-108.
Underhill LG, Loftie-Eaton M and Navarro R. 2018. Dragonflies and damselflies of the Western Cape – OdonataMAP report, August 2018. Biodiversity Observations 9.7:1-21
Animal Demography Unit, Department of Biological Sciences, University of Cape Town, Rondebosch, 7701 South Africa; Biodiversity and Development Institute, 25 Old Farm Road, Rondebosch, 7700 South Africa
Megan Loftie-Eaton
Animal Demography Unit, Department of Biological Sciences, University of Cape Town, Rondebosch, 7701 South Africa; Biodiversity and Development Institute, 25 Old Farm Road, Rondebosch, 7700 South Africa
Rene Navarro
Animal Demography Unit, Department of Biological Sciences, University of Cape Town, Rondebosch, 7701 South Africa; FitzPatrick Institute of African Ornithology, Department of Biological Sciences, University of Cape Town, Rondebosch, 7701 South Africa
What is this document about, and for whom was it written?
This paper is about the Odonata (dragonflies and damselflies) of the Western Cape. It contains a summary of the information in the combined database of the OdonataMAP project and the ODA initiative. It provides a species list for the province. It gives instructions that enable the reader to obtain up-to-date distribution maps for each species, and to obtain up-to-date lists of species for quarter degree grid cells in the Western Cape.
The main users will be the citizen scientists who collect photographic data of dragonflies and damselflies and submit it to OdonataMAP. We believe the information contained here will be useful for planning purposes, and to guide citizen scientists to the areas within the Western Cape where the data needs are greatest.
The paper also aims to provide a model for the presentation of biodiversity data in such a way that can be used by managers and policy makers, by researchers, and by conservation advocacy NGOs. For these groups of people it aims (1) to provide a snapshot, at a point in time, of the quality and volume of data available for the Western Cape, and (2) to provide links to the relevant databases, so that they have access to useful summaries of the ongoing data collection effort. The data can clearly be repackaged in many different formats (for example, species lists for individual sites, such as nature reserves). The aim here is to provide a broad brush overview at the provincial level.
What are the headlines?
In the two-year period 1 July 2016 to 30 June 2018, citizen scientists added seven species to the list of dragonflies and damselflies in the Western Cape, bringing the total to 76 species (Figure 1).
The database available for this report contained 11,267 records of dragonflies and damselflies. This includes the specimen record dating back to the start of the 20th century.
Of these records 2,433 records (22%) were added between July 2016 and June 2017, and 4,202 (37%) between July 2017 and June 2018.
Thus 59% of the entire Western Cape database of records of dragonflies and damselflies was contributed by citizen scientists in two years.
Fig 1. This was the third record of the Vagrant Emperor Anax ephippiger in the Western Cape. Somerset West, 15 May 2017, Corrie du Toit. (http://vmus.adu.org.za/?vm=OdonataMAP-33845)
Where is the study area?
The Western Cape is a province of South Africa, situated on the southwestern section of the country (Figure 2). Of South Africa’s nine provinces, it is the fourth largest with an area of 129,449 km2. The Western Cape is the third most populated province, with an estimated 6.5 million inhabitants in 2017 (Statistics South Africa 2017).
Fig 2. Map of the Western Cape, showing some of the keys centres of human population, and the main road network.
The Western Cape Province is roughly L-shaped, extending northward and eastward from the Cape of Good Hope, in the southwestern corner of South Africa. It stretches 400 km northward along the Atlantic Ocean coast, about halfway to Namibia, and 500 km eastward along the south coast, ending at Natures Valley on the Indian Ocean. It is bordered on the north by the Northern Cape and on the east by the Eastern Cape.
The province has large variation in rainfall, with the eastern end, bordered by the warm Indian Ocean, being almost forest, and the northern end, bordered by the cold Atlantic Ocean, being semi-desert. This wet-dry gradient has a strong influence on the distribution of Odonata within the province. The other major factor in Odonata distribution is a series of almost linear ranges of mountains, roughly parallel to the coast, but at varying distances from it.
There are 262 quarter degree grid cells (Figure 2) which are entirely or partly within the Western Cape. 186 are entirely within the Western Cape. 76 are partly within the Western Cape; 52 are shared with the Northern Cape, 22 are shared with the Eastern Cape, and there are two which are shared between the three provinces (3124CA Winterhoekberge and 3124CC Winterhoek). This report is based on all 262 grid cells which are “in” the Western Cape.
What data are available for the dragonflies and damselflies in the Western Cape?
On 14 August 2018, there were 11,267 records of Odonata in the combined database of OdonataMAP and the Odonata Database of Africa (ODA), recorded since 1980 for Western Cape (Table 1). These were the records strictly within the boundaries of the Western Cape. Of these, 8,938 (80%) had been submitted by citizen scientists as photographic records and the balance were from ODA.
The Odonata Database of Africa (ODA) is an open access database developed by a JRS-funded project (Clausnitzer et al. 2012, Dijkstra 2016). It contains records of the distribution of dragonflies and damselflies across Africa and includes most of the museum specimen records for the region. It is available online as the African Dragonflies and Damselflies Online (ADDO) (http://addo.adu.org.za/). ADDO is a collaboration between the Department of Conservation Ecology and Entomology (University of Stellenbosch) and the ADU (University of Cape Town). Although the two databases are separate, search queries made to the OdonataMAP database can include a search of the Odonata Database of Africa. This was done for this report. This collaboration represents a major consolidation of data resources.
The records in the database are georeferenced, often to an accuracy of metres. But for the purposes of this report each record has been allocated to its “quarter degree grid cell”, a well-known mapping standard in South Africa, which has been used for many biodiversity atlases. The quarter degree grid cells are defined on a geographical grid, and are 15 minutes of latitude north to south, about 27 km, and 15 minutes of longitude east to west, about 25 km at the latitude of the Western Cape (Figure 2). Each quarter degree grid cell has a six-character code, and a name, usually that of a town (or farm) in the grid cell. Exact localities are not disclosed in this report, but are available to anyone with a bona fide need for them.
The Western Cape section of the database has seen spectacular growth over the past two years: 2,433 records were added between July 2016 and June 2017, and 4,202 between July 2017 and June 2018. The total for the six-year period from 2010 to June 2016 was 2,275 records (Loftie-Eaton et al. 2018). In percentages, 22% of the database was added in the 2016/17 year, and 37% in the 2017/18 year. Thus 59% of the 11,267 records in the Western Cape database was contributed by citizen scientists in two years.
Table 1: The 76 species of Odonata (dragonflies and damselflies) in the Western Cape based on the combined databases of OdonataMAP and ODA (see text). The species are sorted first by family, then genus and species names. The Red List (RL) classification of the species is that of Samways and Samaika (2016) and the eight species in threat categories are in boldface. The quantitative information is the number of quarter degree grid cells, in the parts strictly within the Western Cape each species has been recorded in since 1980 (QDGC), and the number of records of the species (N). The final column gives the last date on which the species was recorded, prior to 14 August 2018, when this table was created from the database.
Family
Species code
Scientific name
Common name
RL
QDGC
N
Last recorded
Aeshnidae
664070
Anaciaeschna triangulifera
Evening Hawker
LC
6
6
23/01/2017
Aeshnidae
664120
Anax ephippiger
Vagrant Emperor
LC
2
3
15/05/2017
Aeshnidae
664140
Anax imperator
Blue Emperor
LC
66
350
30/07/2018
Aeshnidae
664170
Anax speratus
(Eastern) Orange Emperor
LC
23
83
05/04/2018
Aeshnidae
664180
Anax tristis
Black Emperor
LC
1
2
01/01/2005
Aeshnidae
664470
Pinheyschna subpupillata
Stream Hawker
LC
27
126
18/03/2018
Aeshnidae
664510
Zosteraeschna minuscula
Friendly Hawker
LC
30
75
14/04/2018
Chlorocyphidae
661180
Platyypha caligata
Dancing Jewel
LC
2
2
12/03/2018
Chlorocyphidae
661210
Platycypha fitzsimonsi
Boulder Jewel
LC
13
100
27/02/2018
Coenagrionidae
662330
Africallagma glaucum
Swamp Bluet
LC
45
202
27/07/2018
Coenagrionidae
662370
Africallagma sapphirinum
Sapphire Bluet
LC
2
3
20/12/2013
Coenagrionidae
662470
Agriocnemis falcifera
White-masked Wisp
LC
6
12
16/12/2017
Coenagrionidae
662630
Azuragrion nigridorsum
Sailing Bluet
LC
21
72
04/05/2018
Coenagrionidae
662720
Ceriagrion glabrum
Common Citril
LC
41
301
15/05/2018
Coenagrionidae
663100
Ischnura senegalensis
Tropical Bluetail
LC
87
859
08/08/2018
Coenagrionidae
663160
Proischnura polychromatica
Mauve Bluet
EN
3
45
21/10/2017
Coenagrionidae
663260
Pseudagrion citricola
Yellow-faced Sprite
LC
11
21
06/02/2018
Coenagrionidae
663300
Pseudagrion draconis
Mountain Sprite
LC
38
254
01/04/2018
Coenagrionidae
663350
Pseudagrion furcigerum
Palmiet Sprite
LC
36
329
30/04/2018
Coenagrionidae
663410
Pseudagrion hageni
Painted Sprite
LC
5
48
26/03/2018
Coenagrionidae
663460
Pseudagrion kersteni
Powder-faced Sprite
LC
43
245
05/06/2018
Coenagrionidae
663820
Pseudagrion massaicum
Masai Sprite
LC
28
160
29/05/2018
Coenagrionidae
663560
Pseudagrion salisburyense
Slate Sprite
LC
3
3
03/12/2009
Coenagrionidae
663880
Pseudagrion sublacteum
Cherry-eye Sprite
LC
1
1
04/05/2018
Gomphidae
664550
Ceratogomphus pictus
Common Thorntail
LC
31
121
08/04/2018
Gomphidae
664560
Ceratogomphus triceraticus
Cape Thorntail
NT
20
58
14/02/2018
Gomphidae
665740
Paragomphus cognatus
Rock Hooktail
LC
38
202
12/03/2018
Gomphidae
665790
Paragomphus genei
Common Hooktail
LC
11
18
21/04/2018
Lestidae
660360
Lestes plagiatus
Highland Spreadwing
LC
7
35
04/05/2018
Lestidae
660330
Lestes tridens
Spotted Spreadwing
LC
3
4
08/04/2018
Lestidae
660300
Lestes virgatus
Smoky Spreadwing
LC
5
21
06/06/2018
Libellulidae
667030
Brachythemis leucosticta
Southern Banded Groundling
LC
1
1
30/04/2017
Libellulidae
667130
Crocothemis erythraea
Broad Scarlet
LC
83
712
06/07/2018
Libellulidae
667140
Crocothemis sanguinolenta
Little Scarlet
LC
46
259
05/06/2018
Libellulidae
667200
Diplacodes lefebvrii
Black Percher
LC
16
60
27/04/2018
Libellulidae
667690
Nesciothemis farinosa
Eastern Blacktail
LC
21
154
01/04/2018
Libellulidae
667780
Orthetrum abbotti
Little Skimmer
LC
1
1
01/01/2004
Libellulidae
667860
Orthetrum caffrum
Two-striped Skimmer
LC
49
244
15/05/2018
Libellulidae
667890
Orthetrum capicola
Cape Skimmer
LC
61
1002
03/08/2018
Libellulidae
667900
Orthetrum chrysostigma
Epaulet Skimmer
LC
22
31
22/06/2018
Libellulidae
667950
Orthetrum julia
Julia Skimmer
LC
40
125
23/03/2018
Libellulidae
668000
Orthetrum machadoi
Highland Skimmer
LC
1
1
01/01/1991
Libellulidae
668120
Orthetrum trinacria
Long Skimmer
LC
37
150
22/04/2018
Libellulidae
668180
Palpopleura deceptor
Deceptive Widow
LC
1
1
23/03/2017
Libellulidae
668190
Palpopleura jucunda
Yellow-veined Widow
LC
13
25
12/03/2018
Libellulidae
668230
Pantala flavescens
Wandering Glider
LC
15
32
22/06/2018
Libellulidae
668370
Rhyothemis semihyalina
Phantom Flutterer
LC
5
11
14/03/2018
Libellulidae
668420
Sympetrum fonscolombii
Red-veined Darter or Nomad
LC
77
531
09/08/2018
Libellulidae
668540
Tetrathemis polleni
Black-splashed Elf
LC
2
2
01/04/2018
Libellulidae
668620
Tramea basilaris
Keyhole Glider
LC
3
3
21/03/2014
Libellulidae
668630
Tramea limbata
Ferruginous Glider
LC
27
106
22/06/2018
Libellulidae
668660
Trithemis annulata
Violet Dropwing
LC
6
31
06/07/2018
Libellulidae
668670
Trithemis arteriosa
Red-veined Dropwing
LC
81
963
31/05/2018
Libellulidae
668800
Trithemis donaldsoni
Denim Dropwing
LC
2
3
05/01/2017
Libellulidae
668870
Trithemis dorsalis
Highland Dropwing
LC
31
104
18/05/2018
Libellulidae
668890
Trithemis furva
Navy Dropwing
LC
58
370
05/06/2018
Libellulidae
669120
Trithemis kirbyi
Orange-winged Dropwing
LC
44
103
30/06/2018
Libellulidae
668900
Trithemis pluvialis
Russet Dropwing
LC
10
79
09/04/2018
Libellulidae
669080
Trithemis stictica
Jaunty Dropwing
LC
40
286
05/05/2018
Libellulidae
669180
Urothemis assignata
Red Basker
LC
1
8
03/05/2018
Libellulidae
669390
Zygonyx natalensis
Blue Cascader
LC
20
63
27/02/2018
Libellulidae
669420
Zygonyx torridus
Ringed Cascader
LC
1
1
18/01/2018
Libelluloidea incertae
666270
Syncordulia gracilis
Yellow Presba
VU
7
82
19/11/2017
Libelluloidea incertae
666280
Syncordulia legator
Gilded Presba
VU
7
28
21/10/2017
Libelluloidea incertae
666290
Syncordulia serendipator
Rustic Presba
VU
3
13
28/03/2016
Libelluloidea incertae
666300
Syncordulia venator
Mahogany Presba
VU
10
34
22/02/2018
Macromiidae
666620
Phyllomacromia picta
Darting Cruiser
LC
6
10
18/11/2012
Platycnemididae
661480
Allocnemis leucosticta
Goldtail
LC
23
162
05/04/2018
Platycnemididae
661790
Elattoneura frenulata
Sooty Threadtail
LC
28
240
18/03/2018
Platycnemididae
661810
Elattoneura glauca
Common Threadtail
LC
31
85
27/02/2018
Platycnemididae
662140
Spesbona angusta
Ceres Streamjack
EN
4
71
30/11/2017
Synlestidae
660070
Chlorolestes conspicuus
Conspicuous Malachite
LC
19
135
22/04/2018
Synlestidae
660120
Chlorolestes fasciatus
Mountain Malachite
LC
5
5
30/03/2018
Synlestidae
660130
Chlorolestes tessellatus
Forest Malachite
LC
12
118
14/05/2018
Synlestidae
660080
Chlorolestes umbratus
White Malachite
LC
23
305
03/08/2018
Synlestidae
660150
Ecchlorolestes nylephtha
Queen Malachite
NT
12
67
06/06/2018
Synlestidae
660160
Ecchlorolestes peringueyi
Rock Malachite
NT
10
99
21/03/2018
Table 2: The number of records of Odonata for each of 157 quarter degree grid cells in the Western Cape, South Africa. The six-character codes for the grid cells are given and the official names of the 1:50,000 map sheets for the grid cell. The final column gives the total number of records available for the grid cell for which identifications have been made at species, genus or family level. The third column gives the number of species in each grid cell, and the fourth column the number of records that were identified to species level. The fifth column provides a count of the overall number of taxa, including species, genus and family.
QDGC
QDGC Name
Species
Records
Taxa
Total
3118AD
Kliphoek
1
1
2
2
3118BB
Douse The Glim
2
2
2
2
3118BC
Wolwenes
1
1
1
1
3118BD
Grootdrif
1
2
1
2
3118CA
Papendorp
1
1
1
1
3118CB
Lutzville
8
9
8
9
3118CC
Doringbaai
1
1
1
1
3118DA
Van Rhynsdorp
7
14
7
14
3118DB
Urionskraal
8
27
9
28
3118DC
Klawer
7
11
7
11
3118DD
Bulshoek
11
15
13
18
3119AC
Nieuwoudtville
13
45
17
53
3119CA
Lokenburg
1
2
2
3
3119CC
Doringbos
4
6
4
6
3124CC
Winterhoek
4
4
4
4
3217DD
Vredenburg
1
1
1
1
3218AB
Lambert’s Bay
2
2
2
2
3218AD
Elandsbaai
6
6
6
6
3218BA
Graafwater
1
1
1
1
3218BB
Clanwilliam
21
39
22
41
3218BC
Redelinghuys
1
1
1
1
3218BD
Oliewenboskraal
12
18
15
24
3218CB
Aurora
2
2
2
2
3218CC
Velddrif
3
3
3
3
3218CD
Bergrivier
2
4
2
4
3218DA
Goergap
4
4
4
4
3218DB
Eendekuil
1
1
1
1
3218DC
Moravia
1
1
1
1
3218DD
Piketberg
8
19
9
20
3219AA
Pakhuis
26
154
31
166
3219AB
Uitspankraal
6
9
6
9
3219AC
Wuppertal
28
103
31
110
3219AD
Grootberg
25
39
25
39
3219BC
Elandsvlei
7
7
7
7
3219BD
Middeldrif
1
1
1
1
3219CA
Citrusdal
23
48
24
51
3219CB
Grootrivier
23
76
24
77
3219CC
Keerom
21
38
21
38
3219CD
De Meul
5
6
7
8
3219DC
Groenfontein
5
7
5
7
3219DD
Kareekolk
2
3
2
3
3220DB
Komsberg
1
1
1
1
3220DC
Kruispad
4
6
4
6
3221DD
Fraserburg Road
1
1
1
1
3222AB
Rosedene
1
1
1
1
3222AC
Paalhuis
3
3
3
3
3222AD
Klipbank
4
4
4
4
3222BA
Kuilspoort
1
1
1
1
3222BB
Renosterkop
3
4
4
5
3222BC
Beaufort West
8
18
8
18
3223AA
Nelspoort
1
1
1
1
3223AD
Oorlogspoort
1
1
2
3
3223BA
Toorfontein
15
26
20
32
3224AA
Toorberg
0
0
1
1
3318AA
Saldanha Bay
5
12
6
13
3318AC
Yzerfontein
2
2
2
2
3318AD
Darling
2
4
2
4
3318BA
Mooreesburg
6
11
7
12
3318BB
Porterville
6
7
6
7
3318BC
Malmesbury
7
10
7
10
3318BD
Riebeek-Kasteel
20
42
21
43
3318CB
Melkbosstrand
7
15
7
15
3318CD
Cape Town
27
377
30
404
3318DA
Philadelphia
5
10
5
10
3318DB
Paarl
26
77
29
80
3318DC
Bellville
25
182
30
193
3318DD
Stellenbosch
42
357
48
382
3319AA
Groot-Winterhoek
22
70
23
71
3319AB
Gydopas
4
4
5
5
3319AC
Tulbagh
27
43
28
44
3319AD
Ceres
39
155
40
156
3319BA
Baviaanshoek
2
4
2
4
3319BB
Inverdoorn
8
10
8
10
3319BC
De Doorns
11
14
11
14
3319CA
Bain’s Kloof
43
573
49
591
3319CB
Worcester
35
109
37
111
3319CC
Franschhoek
38
389
43
396
3319CD
Villiersdorp
33
134
34
135
3319DA
Nuy
9
10
9
10
3319DB
Koo
10
17
10
17
3319DC
Langvlei
5
7
5
7
3319DD
Robertson
19
43
19
43
3320AC
Touwsrivier
1
1
1
1
3320AD
Bloutoring
5
6
5
6
3320BA
Matjiesfontein
2
2
2
2
3320BC
Fisantekraal
1
2
1
2
3320CB
Allemorgens
4
6
4
6
3320CC
Montagu
10
13
10
13
3320CD
Scheepersrus
10
28
10
28
3320DA
Kareevlakte
3
3
3
3
3320DB
Plathuis
2
2
2
2
3320DC
Barrydale
17
25
19
27
3320DD
Warmwaterberg
7
10
8
11
3321AC
Vleiland
4
4
5
5
3321AD
Ladismith
33
85
33
85
3321BC
Matjiesvlei
14
22
17
26
3321BD
Kruisrivier
1
1
1
1
3321CA
Algerynskraal
4
4
4
4
3321CB
Van Wyksdorp
1
1
1
1
3321CC
Muiskraal
1
1
1
1
3321DA
Calitzdorp
7
7
9
13
3321DB
Vleirivier
1
1
1
1
3321DC
Langberg
5
6
5
6
3321DD
Attakwaskloof
1
1
1
1
3322AA
Prince Albert
1
1
1
1
3322AC
Kangogrotte
15
54
19
62
3322AD
Rosselerf
7
11
9
15
3322BA
Seekoegat
1
1
1
1
3322BC
De Rust
3
4
3
4
3322CA
Oudtshoorn
8
11
8
11
3322CB
Dysselsdorp
14
41
15
44
3322CC
Jonkersberg
22
60
26
65
3322CD
George
27
144
31
170
3322DA
Stompdrift
18
49
21
58
3322DB
Buffelsdrif
1
1
1
1
3322DC
The Wilderness
41
594
48
633
3322DD
Karatara
39
354
42
377
3323AC
Barandas
10
15
10
15
3323AD
Willowmore
5
7
5
7
3323BC
Willowmore (East)
4
4
4
4
3323CA
Uniondale
4
4
4
4
3323CC
Kruisvallei
40
383
47
422
3323CD
The Crags
32
111
36
115
3323DA
Voorkloof
1
1
1
1
3323DC
Nature’s Valley
46
594
52
612
3418AB
Cape Peninsula (central)
21
239
26
269
3418AD
Cape Peninsula (Cape Point)
16
42
16
42
3418BA
Mitchells Plain
16
38
16
38
3418BB
Somerset West
36
2166
49
2230
3418BD
Hangklip
42
1212
51
1268
3419AA
Grabouw
36
116
38
118
3419AB
Caledon
16
39
17
40
3419AC
Hermanus
21
52
22
53
3419AD
Stanford
22
117
25
122
3419BA
Greyton
33
179
39
195
3419BB
Riviersonderend
10
21
11
23
3419BC
Jongensklip
2
2
2
2
3419BD
Napier
6
6
6
6
3419CB
Gansbaai
15
82
18
89
3419DA
Baardskeerdersbos
7
9
8
10
3419DD
Elim
2
2
2
2
3420AA
Stormsvlei
1
1
1
1
3420AB
Swellendam
40
177
44
184
3420AD
Wydgelee
3
6
3
6
3420BB
Heidelberg
15
23
15
23
3420BC
Malgas
6
11
6
11
3420CA
Bredasdorp
11
14
11
14
3421AB
Riversdale
1
1
1
1
3421AC
Vermaaklikheid
9
10
9
10
3421AD
Stilbaai
16
51
16
51
3421BA
Albertinia
1
1
1
1
3421BB
Herbertsdale
2
2
2
2
3422AA
Mosselbaai
27
219
32
269
3422AB
Pacaltsdorp
6
12
6
12
3422BB
Sedgefield
18
122
22
130
3423AA
Knysna
22
86
23
88
3423AB
Plettenberg Bay
21
59
22
60
Fig 3. Numbers of species of dragonflies and damselflies recorded per quarter degree grid cell in the Western Cape. Based on OdonataMAP database, January 1980 to August 2018.
Of the 262 quarter degree grid cells “in” the Western Cape, there is at least one species of dragonfly or damselfly for 157 (60%) of them (Table 1, Figure 3). The total number of records submitted for these grid cells was 11,885 (Table 2), reflecting the fact that there were 618 records in the sections of the 74 grid cells which were part of the Northern Cape or Eastern Cape.
From this database, a total of 76 Odonata species were recorded in the Western Cape (Table 1). The Cape Skimmer Orthetrum capicola had the most, 1002, records; the most recent observation was on 3 August 2018, 11 days prior to the data extraction for this report (Table 1). The second most abundant species was Red-veined Dropwing Trithemis arteriosa with 963 records, followed by Tropical Bluetail Ischnura senegalensis (859), Broad Scarlet Crocothemis erythraea (712) and Red-veined Darter Sympetrum fonscolombii (531). There were 26 species with between 100 and 500 records, and 23 with between 20 and 99 records. The five species with between 10 and 18 records, and the 18 species with fewer than 10 records were all given careful consideration, with checks to confirm identifications. Eight of the 76 species recorded in the Western Cape were in IUCN Threat Categories (Table 1).
Two quarter degree grid cells had more than a thousand records: 3418BB Somerset West had 2,230 and 3418BD Hangklip had 1,268 (Table 2), both on the eastern side of False Bay. There were 25 grid cells with 100 or more records, and 57 with between 10 and 99 records.
How many new species been added to the Western Cape list recently?
Amazingly, seven species of Odonata were added to the Western Cape list in the most recent two years, 2016/17 and 2017/18.
There are three records of the Vagrant Emperor Anax ephippiger in the Western Cape. They come from two quarter degree grid cells: two records, in April and May 2017, from distinct sites within 3219AA Pakhuis in the northern Cederberg range; one record, in May 2017, in quarter degree grid cell 3418BB Somerset West (Figure 1). The nearest record to these is in the Great Karoo in the Northern Cape, from quarter degree grid cell 3022CA Garskolk near Carnarvon, made in December 2016. There are five records in the Eastern Cape in three quarter degree grid cells: from west to east these are from 3324DD Hankey in March 2017, three from 3325DC Port Elizabeth in May 2017, November 2017 and February 2018, and from 3237CB Stutterheim, an older record from March 2006.
Fig 4. The third record of Spotted Spreadwing Lestes tridens in the Western Cape. Plettenberg Bay, 6 January 2018, Andre Marais. (http://vmus.adu.org.za/?vm=OdonataMAP-42514)
The Spotted Spreadwing Lestes tridens also has four Western Cape records, all at the eastern end of the Western Cape, with a scattering of records in the adjacent part of the Eastern Cape. The Western Cape records, arranged from west to east are in three quarter degree grid cells 3322CD George in April 2018, 3322DC The Wilderness in December 2016 (two records), and 3423AB Plettenberg Bay in January 2018 (Figure 4). Over the border in the Eastern Cape, there are six records from quarter degree grid cell 3424BA Kruisfontein (with Oyster Bay as a more well-known locality within the grid cell) dated between January and April 2017, one record from the adjacent quarter degree grid cell 3424BB Humansdorp in September 2014, six records from quarter degree grid cell 3325CC Loerie dated between December 2017 and April 2018. There are four more records between Port Elizabeth and East London, then a gap to the KwaZulu-Natal border, and many records in the start of the core of the distribution, along the KwaZulu-Natal coast.
There are eight records of Red Basker Urothemis assignata in the Western Cape, all made in the quarter degree grid cell 3322DD Karatara, immediately north of Sedgefield (Figure 5). The eight records were made by three observers at two localities between February and May 2018. There is a single record in the Eastern Cape (quarter degree grid cell 3325DC Port Elizabeth) made in May 2017. There are multiple records in coastal KwaZulu-Natal.
Fig 5. The seventh record of Red Basker Urothemis assignata in the Western Cape. Karatara, inland from Sedgefield, 1 May 2018, Andre Marais. The first record had been made only three months earlier (http://vmus.adu.org.za/?vm=OdonataMAP-50295)
The Denim Dropwing Trithemis donaldsoni has three Western Cape records from two quarter degree grid cells, which are both in the interior: 3119CC Doringbos, north of the Cederberg range, in November 2016, and 3321BC Matijesvlei, north of Calitzdorp (two records in January in 2017). There are no records for the Eastern Cape and a single record for the Northern Cape in 2823DA Danielskuil, northwest of Kimberley, in January 2017. This record is itself vastly out of the known range, in the savanna biome in the northeast of South Africa.
The first Western Cape record of the Cherry-eye Sprite Pseudagrion sublacteum was made in January 2018 in quarter degree grid cell 3323DC Nature’s Valley, close to the border with the Eastern Cape. There are seven records of Cherry-eye Sprite from five quarter degree grid cells in the western half of the Eastern Cape in the database, all dated 2014 or later; the suggestion is that the distribution of this species is moving westwards from KwaZulu-Natal through the Eastern Cape and has recently reached the Western Cape.
The single record of Southern Banded Groundling Brachythemis leucosticta for the Western Cape was made in April 2017, in quarter degree grid cell 3320CC Montagu (Figure 6). The nearest records are in the western Eastern Cape, with four records in quarter degree grid cell 3325CD Uitenhage, west of Port Elizabeth. There is a thin scattering of records along the Eastern Cape coast, all dating from 2012 or later, suggesting that the distribution of Southern Banded Groundling is expanding westwards along the coast from KwaZulu-Natal.
Fig 6. The first record of Southern Banded Groundling Brachythemis leucosticta in the Western Cape. Montagu, 30 April 2017, Shaun Hayes, Christine Hayes and Kathy de Wet. (http://vmus.adu.org.za/?vm=OdonataMAP-34004)
The single record of Deceptive Widow Palpopleura deceptor for the Western Cape was made in March 2017, in quarter degree grid cell 3319BB Inverdoorn, south of the Cederberg range, north of Ceres. There is a single record for the Eastern Cape, from quarter degree grid cell 3129CB Tombo (near Port St Johns) and there are eight records, from four quarter degree grid cells for KwaZulu-Natal.
There are two alternative explanations of the occurrence of these species in the Western Cape. They have been present for decades, but have been overlooked until the proliferation of citizen science observers and observations associated with OdonataMAP. Alternatively, these are genuine range expansions. Many bird species have, during various decades of the past 50 years, extended their ranges westwards into the Western Cape. Well known examples are Hadeda Ibis Bostrychia hagadash and Fork-tailed Drongo Dicrurus adsimilis (Ainsley et al. 2016, Second Southern African Bird Atlas Project unpubl. data). Perrisnotti et al. (2011) reported on range expansions in South Africa between 1980s and the 2002 of some conspicuous insects: fruit chafers (Coleoptera, Scarabaeidae, Cetoniinae), longhorn beetles (Coleoptera, Cerambycidae) and butterflies (Lepidoptera, Rhopalocera). All except one of the eight species they considered showed range expansions of the order of 500-800 km from KwaZulu-Natal in the direction of the Western Cape along the coastline. Although the evidence is anecdotal, it seems that the Golden Orb-web Spider (or Black-legged Nephila) Nephila fenestra expanded its range westwards reaching the Cape Peninsula in the first 10 years of the 21st century, and have become abundant.
How do I obtain lists of species for quarter degree grid cells?
Up-to-date lists of the species recorded in a quarter degree grid cell can be obtained from the following link: https://www.slideshare.net/Animal_Demography_Unit/how-to-create-a-species-list-from-the-virtual-museum-data The list of grid cell codes is provided in Table 1. In the link below, replace the “locus” with the code for the QDGC required (consult also Figure 2). The link below provides the species list for the quarter degree grid cell 3219AA Pakhuis, in the northern Cederberg:
http://vmus.adu.org.za/vm_locus_map.php?vm=OdonataMAP&locus=3219AA.
This link provides a map of the quarter degree grid cell, a list of the species recorded in it, the number of records for each species and the date of the most recent record. In addition, you can look at all the details for all the individual records of a species. It is also possible to get the list of all the records for the quarter degree grid cell. These are presented in batches of 30 records. This feature is particularly useful if there is a relative handful of records for a grid cell, and you want to see the details for all of them at once.
How up-to-date is the database?
In Table 1, the most recent date on which each of the 77 species has been recorded in the Western Cape is provided in the last column. The median of these dates was 5 April 2018; in other words, half of the species recorded in the Western Cape have been recorded there since 5 April, in the most recent four months prior to the download of the database for this. Of the 77 species, 59 species had last been recorded in the Western Cape during 2018 and a further 10 during 2017 (Table 1). This is a remarkable achievement. Seven of the eight species in IUCN threat categories had most recently been recorded in 2017 or 2018, and one Rustic Presba Syncordulia serendipator was last recorded in March 2016 (Table 1, Figure 8).
Fig 8. The most recent record of the Vulnerable Rustic Presba Syncordulia serendipator was made near Stellenbosch on 28 March 2016 by Corrie du Toit. (http://vmus.adu.org.za/?vm=OdonataMAP-21577)
In the same way as the up-to-dateness of the provincial database can be assessed using the median of the most recent date for each species, this same approach can be applied to individual quarter degree grid cells. This median date is calculated and presented whenever the species list for a grid cell is downloaded (see section above). Special fieldwork attention needs to be paid to quarter degree grid cells for which the median date is more than three years from the present. For example, quarter degree grid cell 3223BA Toorfontein, in the Great Karoo near Murraysburg, contains 15 species, but their median date is 24 January 2013, more than five years ago. The species list for this grid cell can be downloaded using http://vmus.adu.org.za/vm_locus_map.php?vm=OdonataMAP&locus=3223BA
Are there species which have not been recorded in recent years?
For four species, the most recent record was prior to 2010. All these records come from the Odonata Database for Africa, and are supported by specimens, mostly curated in the Stellenbosch University Entomology Collection.
The Highland Skimmer Orthetrum machadoi has been recorded only once in the Western Cape, in 1991, in quarter degree grid cell 3219CB Grootrivier, in the southern Cederberg range. Until 2017, the nearest records to this one were in KwaZulu-Natal. However, in February 2017, Highland Skimmer was recorded in the western Eastern Cape, in QDGC 3325CB Uitenhage North (http://vmus.adu.org.za/?vm=OdonataMAP-30854), and seven further records have been made from this locality.
There is a single record of Little Skimmer Orthetrum abbotti for the Western Cape, made in 2004 in quarter degree grid cell 3421AC Vermaaklikheid, along the south coast. There are OdonataMAP records for this species in five grid cells of the Eastern Cape, two of which are near Port Elizabeth (3325CC Loerie, four records in May 2018, and 3325CB Uitenhage North, 16 records between November 2017 and April 2018).
Both Western Cape records of the Black Emperor Anax tristis were made in 2005 in quarter degree grid cell 3418BD Hangklip, which includes the village of Bettys Bay. The nearest record was made in quarter degree grid cell 2930CB Pietermaritzburg in KwaZulu-Natal in 1991, with recent records slightly to the northeast (2830DA Collessie in November 2012 and 2831DA Nkwalini in January 2018).
There are three records of the Slate Sprite Pseudagrion salisburyense in the eastern half of the Western Cape: in quarter degree grid cells 3321AD Ladismith in 2005, in 3322CA Oudtshoorn in December 2009 and in 3323DC Nature’s Valley in April 2008. There is a scattering of records throughout the Eastern Cape.
The continued occurrence of these four species in the Western Cape needs confirmation. The first place to search is at the location of the original discovery.
What are the priority areas for data collection in the Western Cape?
There were 156 quarter degree grid cells in, or partially in, the Western Cape with at least one species of dragonfly or damselfly identified to species level (Table 2, Figure 3). The largest number of species record in a quarter degree grid cell was 46 (in 3323DC Nature’s Valley, at the eastern limit of the province (Figure 2). 13 quarter degree grid cells had 36 or more species, and are shaded brown in Figure 3, and a further 12 had between 24 and 35 species, and were shaded dark green-brown in Figure 3.
These 25 quarter degree grid cells are characterised by areas of rugged and mountainous terrain. The grid cells of the mountains of the Boland, immediately east of Cape Town, show consistently large species richness, as do the mountains along the Garden Route in the eastern edge of the Western Cape. The intervening mountain ranges have patchy coverage. In simplistic terms, there are ranges of mountains to the south and the north of the Little Karoo. The main range to the south is the Langeberg; the quarter degree cell 3420AB Swellendam which lies along this axis has 40 species. The range to the north is known as the Groot Swartberge; within this range, quarter degree grid cell 3321AD Ladismith has 33 species. This gap, between the eastern and western ends of the Western Cape, probably represents the biggest challenge of fieldwork in the province, in the summer of 2018/19.
The second biggest challenge lies north of the mountains of the Boland, towards the Cederberg, and northwards along the Escarpment immediately inland of Vanrhynsdorp.
The third challenge is the Great Karoo, where the majority of the quarter degree grid cells without any coverage lie. The fact that quarter degree grid cell 3223BA Toorfontein, south of Murraysberg, has a list of 15 species (Table 2) is indicative of what is achievable in the Great Karoo.
The fourth coverage challenge lies in the Swartland and Overberg regions north and east of Cape Town, respectively. Large parts of these regions are almost totally transformed to agriculture, with complete loss of natural habitats to fields of wheat and canola, to vineyards and to orchards. A sensible strategy in these areas would be to increase the number of records per quarter degree grid cell to at least 50, and preferably 100, and to examine the species accumulation curves. Three candidate quarter degree grid cells in the Swartland, chosen only because they are conveniently close to Cape Town, are 3318DA Philadelphia (five species, 10 records), 3318BC Malmesbury (seven species, 10 records) and 3318BA Moorreesburg (six species, 12 records) (Table 2).
Any quarter degree grid cell in the Western Cape with fewer than 100 records should be regarded as a priority. That excludes only 25 grid cells (Table 2). Even for the grid cells with large volumes of data, every record should be submitted to the OdonataMAP database. There are three reasons for this: (1) it “refreshes” the record for the species, confirming the continued presence of the species in the grid cell; (2) it is only in the grid cells with the most data that studies of changes in species composition through time are going to be feasible; (3) every record contributes to our understanding of the “phenology” (the flight period) of the species. Studies of phenology require large data volumes.
How do I go about participating in data collection for this project?
In a nutshell, the protocol is simple. Take photos of dragonflies and damselflies, and upload them to the OdonataMAP section of the Virtual Museum website. There is no need to identify the species in the photograph. This gets done by an expert panel.
There is a slideshow entitled “How to shoot your dragon” at https://www.slideshare.net/Animal_Demography_Unit/how-to-shoot-your-dragon
Taking photographs of dragonflies and damselflies is less challenging than most people anticipate. Most individuals have a perch which they return to routinely after each foraging flight and generally remain on the perch for long enough for several photographs to be taken, from different angles. The foraging flights seldom last for more than a few minutes, so a measure of patience is required. Each time they land, they tend to perch differently, so this provides an opportunity to take photographs at several angles. The entire spectrum of cameras are in use; the most versatile for this type of photography are the new generation of “compact” cameras
Before you can upload into the Virtual Museum you need to register as a citizen scientist. The procedure for doing this is described here: https://www.slideshare.net/Animal_Demography_Unit/how-to-register-as-a-citizen-scientist-with-the-animal-demography-unit
Once you are registered you logon to the website using your email address and password. A “Data upload” section now becomes visible. The critical information that needs to be uploaded into the database is date, place and a series of one to three photographs of a single species, usually different angles on the same individual. Guidance on the upload process is provided in this slideshow: https://www.slideshare.net/Animal_Demography_Unit/how-to-submit-records-to-the-virtual-museums
The expert panels for each project consists of taxon experts and the most experienced citizen scientists. For OdonataMAP, many records get confirmed identifications within a week. Some records take longer, and for some photographs a positive identification to species level is not possible. Records are sometimes identified to genus or family level. Some species can readily be identified from a poor, even partially blurred photograph. At the other extreme a few species can only be identified in the hand. As a beginner participant, the best strategy for a positive confirmed identification is to submit the best one, two or three photographs, preferably from different angles. The most important parts of the dragonfly or damselfly to get in sharp focus are the thorax and a wing.
There is an exceptional fieldguide to the dragonflies and damselflies of South Africa. It was written by Warwick and Michèle Tarboton. It is called A Guide to the Dragonfllies and Damselflies of South Africa, and published by Struik Nature. It describes and illustrates 164 species of Odonata recorded in South Africa at the time of publication (Tarboton & Tarboton 2015). It is widely available in good bookshops, and an ebook version is also available (see https://www.warwicktarboton.co.za/Dragonfly%20Book.html).
Acknowledgements
Many friends and colleagues made helpful suggestions which improved this report: Sharon Stanton, Eugene Moll, John Wilkinson, Alan Manson, Warwick Tarboton and Lappies Labuschagne. Pete Laver prepared the maps. We acknowledge funding from the JRS Biodiversity Foundation, Seattle, USA. But above all, we celebrate the amazing contributions made by the citizen scientists responsible for 80% of the data upon which this report is based.
References
Ainsley J, Underhill LG, López Gómez M, Brooks M 2016. Bird distribution dynamics 8 – Hadeda Ibis Bostrychia hagedash in South Africa, Lesotho and Swaziland. Biodiversity Observations 8.6: 1-10. Available online at https://journals.uct.ac.za/index.php/BO/article/view/404Clausnitzer V, Dijkstra K-DB, Koch R, Boudot J-P, Darwall WRT, Kipping J, Samraoui B, Samways MJ, Simaika JP, Suhling F 2012. Focus on African freshwaters: hotspots of dragonfly diversity and conservation concern. Frontiers in Ecology and the Environment 10: 129-134.
Dijkstra, K-DB 2016. African Dragonflies and Damselflies Online. (Version 1 July 2016). Available online at http://addo.adu.org.za .
Loftie-Eaton M, Underhill LG, Navarro R 2018. OdonataMAP: progress report on the atlas of the dragonflies and damselflies of Africa, 2016/17 and 2017/18. Biodiversity Observations.
Perissinotto R, Pringle EL, Giliomee JH 2011. Southward expansion in beetle and butterfly ranges in South Africa. African Entomology 19: 61-69.
Samways MJ, Simaika JP 2016. Manual of Freshwater Assessment for South Africa: Dragonfly Biotic Index. Suricata 2. South African National Biodiversity Institute, Pretoria.
Statistics South Africa 2017. Mid- year population estimates. Available online at http://www.statssa.gov.za/publications/P0302/P03022017.pdfTarboton W, Tarboton M 2015. A Guide to Dragonflies and Damselflies of South Africa. Struik Nature, Cape Town.
Underhill LG, Navarro R, Manson AD, Labuschagne JP, Tarboton WR 2016. OdonataMAP: progress report on the atlas of the dragonflies and damselflies of Africa, 2010-2016. Biodiversity Observations 7.47: 1-10. Available online at https://journals.uct.ac.za/index.php/BO/article/view/340
Water, birds, and biodiversity – key elements of education
John Fincham
Cape Bird Club member & SABAP2 atlaser, Cape Town, South Africa
Skhumbuzo Mbewu
Tour Guide & SABAP2 atlaser, Cape Town, South Africa
Jo Hobbs
Cape Bird Club member & SABAP2 atlaser, Cape Town, South Africa
Introduction
Current and historical Facts
Given the reality of the water crisis in the Western Cape (WC), especially in the City of Cape Town and the satellite towns, a unique opportunity exists to use the combination of the Paarl Bird Sanctuary and the Drakenstein Waste Water Treatment Works (PBS/WWTW) for education about water and related facts. Severe drought is not the only reason for the shortage of fresh water. It is likely that the water requirements of the burgeoning human population of the province, together with the need to use water to irrigate food crops, now exceed the water resources of the WC, despite the storage created in dams. An associated fact is that in the WC a large proportion of employed people work in Agriculture, both directly and indirectly. So any cut in water for irrigation, would increase unemployment and intensify poverty, which are already huge problems. The overall predicament has country-wide, and even global implications, emphasising the need for water-related education.
The PBS/WWTW complex is situated on the east bank of the Berg River, about 30 km from the source, which is in the mountains above Franschhoek. This riverside location creates the responsibility to constantly ensure good water quality for downstream use by people and agriculture. It also provides an exceptional opportunity for environmental and health education, from schoolchildren to students at universities. For schools in particular, the venue can be an open-air classroom that excites and holds the attention of scholars, thereby increasing the educational impact of the available resources. Opportunities for research projects, tourism and recreation are also substantial. By contrast, the processed water from the Strandfontein WWTW at Cape Town flows directly into the sea without any reuse by people. However, the water crisis in the City is likely to soon compel recycling of the Strandfontein water.
Some of the history of PBS has been described (Schmidt 1996, Cohen, Spottiswoode & Rossouw 2006, Harebottle et al. 2008, Hobbs 2018). The seven existing pans form a substantial artificial wetland covering approximately 50 hectares (Figure 1). In recent years the waste water treatment process has been modernised, and final water quality is monitored in an on-site laboratory. The return of water to the river throughout the year contributes to a sustained flow for human and other uses, in towns and on farms downstream. In the dry summer months the proportion of treated water in the flow volume of the river, increases.
Fig.1 Paarl Bird Sanctuary is bordered by the Berg River and vineyards to the west, with industrial and residential areas to the east. Pans A-D form an artificial wetland that attracts prolific birdlife, and from which treated waste water feeds back to the river for reuse downstream.
In addition to the exceptional educational potential of the process of treating waste water for reuse, especially by people, the PBS artificial wetland and the adjacent Berg River, create an important opportunity for learning about biodiversity, especially as regards birds and invasive vegetation on the river banks. Key aspects of these components have not been described previously and are the main focus of this paper.
Bird counts at PBS
Monthly counts of water-associated birds at PBS are in the 24th year, and no count has been missed. Data for the first 10 years of counts has been analysed and published (Harebottle et al. 2008). It was concluded that PBS was second only to Strandfontein WWTW (now known as the Birding Section of the False Bay Nature Reserve) for conservation of water-associated birds in the Cape Town area. Furthermore, PBS supports 11 universally and regionally important species for monitoring numbers and migrations. A recommendation was that PBS qualifies globally and regionally as an Important Bird Area and a Ramsar Site.
The Grey-headed Gull Chroicocephalus cirrocephalus (Figure 2) is a sought-after bird that is numerous and approachable at PBS. The list of species seen regularly is substantial (Cohen, Spottiswoode & Rossouw 2006, Harebottle et al. 2008) Exciting vagrants that are occasionally present include Squacco Heron Ardeola ralloides, African Jacana Actophilornis africanus, Lesser Flamingo Phoeniconaias minor (nomadic), Little Bittern Ixobrychus minutus, and Goliath Heron Ardea goliath.
Fig 2. A Grey-headed Gull (Chroicocephalus cirrocephalus) sitting on nestlings. These gulls are numerous at PBS and allow a close approach, which facilitates photography.
Recent problems at PBS
It is on record that in 2004 thousands of local and international birders visited PBS (Harebottle et al. 2008). By 2017 the number of visitors had dwindled to a few at weekends only, and under security cover, because of robberies, sometimes with violence. The adverse publicity from this criminal activity has been disseminated widely, including online and by social media. Moreover, facilities have been repeatedly vandalised. The Yvonne Weiss bird lookout platform is a concrete and brick structure that provides high-level views over five pans (Figure 3). Below the platform there is an undercover area that can be used for audiovisual aids like videos, slide projection, and poster displays (Figure 4). There are also toilets. It was originally funded jointly by the Drakenstein Municipality and the Rowland & Leta Hill Trust. It has been severely vandalised twice. To try to stop further vandalism, it is now surrounded by high security fencing topped by razor wire; strong locked gates; pepper spray in the toilets (activated automatically at night); 24 hr CCTV camera surveillance; and flood lighting at night. It is currently only open to visitors over weekends because of the threat of vandalism and robberies.
Fig 3. The Yvonne Weiss bird lookout platform is a substantial structure that is a useful part of the outdoor classroom because the upper deck overlooks five pans. Here the waste water treatment process is being explained in Afrikaans, to children from Dalweide Primary School.Fig 4. Children watching a video showing microscopic, commensal organisms that occur normally in clean water. They are in the undercover part of the Yvonne Weiss bird lookout facility, which is also suitable for other teaching aids, such as projecting slides and showing posters.
“Donated by the Cape Bird Club” was the inscription on a plaque in the Rita Meyer/Sand Island bird hide, which was built by Paarl Boy Scouts (Schmidt 1996). This hide, and three others, have been destroyed by vandals, were rebuilt, and destroyed again. Since 2010 there have been about 10 robberies in PBS, three of which involved minor stabbings, and one couple was threatened with a firearm. These incidents are less serious and not as frequent as in some other areas. To counter crime, PBS is now only open at weekends when security officials are in attendance. Birders are instructed to stay in their cars and use them as hides by parking at cleared vantage points. Since these arrangements came into force visitor numbers have started to increase slowly.
Human population pressure
There is an ongoing increase in the population in the Mbekweni and Groenheuwel suburbs of Paarl along the eastern side of PBS. The provision of housing has been overwhelmed, so that many people are living in shacks under conditions of poverty, with a high rate of unemployment (Figure 5).
Fig 5. Human population pressure is high along the eastern side of PBS. Many people live in shacks under conditions of poverty, and there is a high rate of unemployment.
Methods
Informing communities through schools
It was proposed that if communities in Paarl, and particularly adjacent to PBS, were informed about the potential of the PBS/WWTW complex for environmental and health education, as well as for tourism, recreation, research and job creation, then they would come to realise these assets needed to be safeguarded and used wisely for their own benefit. The principle that local community support is essential for recreational and wildlife areas, and National Parks, is widely known and accepted.
The Drakenstein Municipality, which is the local government authority for the area, requested a business plan as a condition for authorisation of the project. A document was accordingly prepared, submitted and accepted by the top municipal management. It proposed to work through schools as an effective way to start to convey key information back to the communities they serve. This plan is on file with the first author.
School Principals arranged meetings with all the teachers at schools in order for the project to be described. There is time gap at 14h00 when teachers can attend meetings. Meetings took place at all the schools serving Mbekweni and Groenheuwel suburbs of Paarl. A total of 205 teachers attended, usually including the Principals. Details of the meetings are summarised in Table 1.
School
Date
Teacher attendance
Langabuya PS
1/3/2016
21
Imboniselo PS
18/4/2016
30
Mbekweni PS
4/5/2016
32
Desmond Tutu HS
5/5/2016
32
Dalweide PS
15/8/2016
25
Groenheuwel PS
6/10/2016
23
Ihlumelo HS
1/3/2016 & 14/9/2017
42
Total
205
Information presented to teachers at school meetings
Emphasis was placed on crucial environmental messages conveyed clearly by birds in five ecosystems. In addition, the need to ensure water quality and flow in the Berg River was explained (as specified previously), as well as the problem of invasive, non-indigenous trees along the river banks. Information was presented by means of discussion supported by visual aids. The teachers were advised that practical examples relating to the information presented could be demonstrated at the nearby PBS/WWTW complex, which is an ideal outdoor classroom for environmental and health education.
Examples of messages conveyed by birds, according to ecosystems they utilise, follow.
Terrestrial birds globally: long distance bird migrants are warning of devastating habitat destruction along flyways that span the earth (Hockey 2012; BirdLife International 2015; Taylor, Peacock & Wanless 2015). The numbers of some of the migrants that reach PBS, such as the Common Sandpiper Actitis hypoleucos, and the White-winged Tern Chlidonias leucopterus, have declined drastically since counts started 23 years ago. Human related pressures are damaging the flyways migrants use in several ways. These include urban sprawl; overgrazing by livestock; destruction of forests and woodlands; agricultural monocultures (crops, forestry and livestock); draining of wetlands; flooding of wetlands by dams; and lethal obstacles in flyways (electricity power lines, wind turbines, fences, roads, and railways). In India, migrating Amur Falcons Falco amurensis (which cross the Indian Ocean to reach Africa) are caught in nets for food (Kumar 2014). In Malta, there is ruthless hunting pressure on migrating birds (Azzopardi 2005), which is also the case in Cyprus and other Mediterranean countries.
Oceanic seabirds: pelagic birds that feed exclusively at sea include albatrosses, penguins, gannets, cormorants, and others. They are in serious trouble because industrialised over-fishing is depriving them of food and killing them as by-catch; and also because we have introduced predators that are killing their chicks on the islands where some of them breed (Crawford & Makhado 2012; Ryan 2012; Davies, Dilley et al. 2015; FitzPatrick Report 2015; Taylor, Peacock & Wanless 2015; Yeld 2015; Knapton 2016, Crawford et al. 2017; Ryan 2017; Wanless 2018). Ultimately there may be no fish left for birds or people because high-tech, mechanised, industrial fishing, was not part of evolution.
Birds regionally in southern Africa: here the avian messengers of disaster are all the vultures, some large eagles (e.g. Martial Eagle Polematus bellicosus, Crowned Eagle Stephanoaetus coronatus, Bateleur Terathophus ecaudatus & Tawny Eagle Aquila rapax), and the Secretarybird Sagittarius serpentarius. In 2015 they were classified as vulnerable, endangered or critically endangered (Taylor, Peacock & Wanless 2015; Ogada et al 2016). In South Africa there are many places named Aasvoëlskop/krans, but the vultures are no longer there. The background to this situation is that the region has been carved into 7 countries and numerous provinces by politicians, with no consideration of environmental impacts. The biomass of ecologically adapted migratory game, that fed vultures and some eagles, may well have exceeded the biomass of current farm animals. Seasonal migration routes have been cut by numerous barriers. Some of these are lethal, such as electricity power lines and the veterinary fences in Botswana and Namibia. Absurdly the fences are a condition for beef importation by the remote European Union. Moreover, there are now extra obstacles in wind turbines, as well as the less intrusive solar energy facilities. The link that follows provides recent information on damage from wind turbines: https://www.fin24.com/Economy/wind-farms-can-be-deadly-20171217-2
Urban birds locally: crows in towns are easy to see and can be important scavengers, indicating the presence of litter that they help to clean up. However, with litter there are inevitably rats, mice, fleas, lice and numerous microscopic pathogens in excreta from humans and animals. When there is promiscuous human defecation on the ground because there are no toilets, children are often infected by helminths, and other intestinal parasites (Fincham et al. 1998). The illustration of a piece of intestine surgically excised from a 3-year old boy because it was blocked by Ascaris lumbricoides worms, emphasises the risk, and elicited shocked gasps from some teachers.
Rural birds locally: away from towns crows must hunt for food. When they decimate tortoises it is an indication of an impoverished rural environment with an imbalanced biodiversity (Figure 6). The crows have moved into a niche vacated by vultures, eagles and other raptors (as described regionally), and tortoises can be a vulnerable residual prey species. (Uys 1966, Simmons & Barnard 2011, Fincham & Lambrechts 2014; Fincham et al. 2015; Fincham & Nupen 2016). Some local tortoise species are on the verge of extinction (Branch 2008).
Fig 6. The carapaces of 315 small tortoises killed by a pair of Pied Crows to feed four chicks and themselves, in the karoo. Additional prey must also have been taken. Photo by Nollie Lambrechts.
Water quality & quantity: natural wetlands are the source of rivers, into which they filter clean water. They are rich in biodiversity, of which birds are a part. Humans take clean water from rivers, emanating from natural wetlands, pollute it seriously (including sewage; other excreta; soaps, detergents and dirt from washing; discharges from hospitals, industry and agriculture), and must then return it to the river because it is needed for use downstream. This situation pertains to the Berg River at Paarl and Wellington. If the water is not cleaned thoroughly, pathogens, toxins and pollutants could be disseminated to communities all the way to Velddrif, at the mouth of the river. A warning of a dangerous situation is when ducks and other water-associated birds die in numbers due to excessive levels of botulism toxin in algae, snails, maggots, mussels & fish that they eat, especially when water is semi-stagnant (Soos & Wobeser 2006). Details of the water treatment process are not the main focus on this paper, but were summarised in introductory talks to teachers and scholars. The need to ensure minimal risk of transmitting water-borne diseases and toxicities downstream was emphasised in the preferred language of each tour group. It was confirmed by Primary and High School teachers that water purification is an important part of the curricula.
Invasive riverine trees: the Berg River and its banks are an ecosystem that is used by birds and a wide range of other organisms. The river banks have been invaded by non-indigenous trees, especially Eucalyptus spp and Black Wattle Acacia mearnsii. These trees need so much water to sustain their prolific growth that the hydrology of the river, as well as the biodiversity of the ecosystem, have both been adversely affected (Marais & Wannenburgh 2008). The river flow has been reduced, and erosion has been enhanced because peak flow pressures on the banks and the bed have changed. Moreover, the unnatural tree cover has compromised many of the indigenous plants and animals associated with the river. A programme is underway to eradicate the invasive trees and restore natural biodiversity (Figure 7).
Fig 7. Clearing of invasive trees from the banks of the Berg River is underway. Indigenous species are being planted to replace the non-indigenous invaders.
School tours
Following the descriptive introduction to the teachers, they were keen to have scholars undertake educational tours of the PBS/WWTW complex. Accordingly groups from two High Schools and three Primary Schools toured the complex, as detailed in Table 2.
Date
School
Scholars
Teachers
1/10/2016
Desmond Mpilo Tutu HS
42
1
2/10/2016
Desmond Mpilo Tutu HS
44
1
22/2/2017
Groenheuwel PS
76
1
23/2/2017
Groenheuwel PS
76
2
24/4/2017
Langabuya PS Scouts
64
2
4/9/2017
Dalweide PS
60
2
6/9/2017
Dalweide PS
60
2
12/9/2017
Dalweide PS
66
2
10/10/2017
Ihlumelo HS
45
2
11/10/2017
Ihlumelo HS
47
2
12/10/2017
Ihlumelo HS
47
2
23/10/2017
Ihlumelo HS
52
2
24/10/2017
Ihlumelo HS
21
1
25/10/2017
Dalweide PS
60
1
26/10/2017
Dalweide PS
30
1
Total
5
790
205
On arrival, each tour group was given a short introductory talk in their preferred language as far as was practical. So they were addressed in Afrikaans by Adam Small and Marshall Diedericks (WWTW); in isiXhosa by Mteteleli Sibaca (WWTW) and Skhumbuzo Mbewu; and in English by Albert van Vuuren (Aquavan consultant) and John Fincham. This helped the children to relax. They were introduced to how we use water, and the necessity for reuse after purification, since available water, sustained by natural wetlands, is limited. A key point was to explain and emphasise biodiversity as being the whole range of interacting, water-dependant life forms (animals and plants) in any ecosystem, including humans.
After this, groups were divided so that half were helped with bird identification by experienced birders, working from the Yvonne Weiss bird outlook platform, using binoculars and spotting scopes. Each child was provided with a laminated sheet (for reuse) with photographs in colour of 24 birds that are always present at PBS, printed on both sides. A score card corresponding to the coloured photos, with thumbnail bird images, gave the bird names in four languages: Afrikaans, English, SeSotho and isiXhosa. Completion of the score card created a competitive task for each individual on the day. The use of spotting scopes and binoculars to facilitate identification of different bird species was an exciting experience for the scholars (Figure 8).
Fig 8. Grade 10 scholars using a scope & binoculars as aids for identifying birds, at PBS. These are important tools for use in outdoor classrooms. The girls are on the Yvonne Weiss bird lookout platform, scanning pan A for birds (see Figure 1).
The other half of each group went on a guided nature walk along the berm between pans E2 & E3 (see Figure 1). On the walk a wide variety of birds were identified. Nests of the Southern Masked Weaver Ploceus velatus were demonstrated. The intricacy and complexity of nest construction by weavers is an important lesson for everyone (Figure 9), and deserves enormous respect. Nests with eggs of the Black-winged Stilt Himantopus himantopus (Figure 10), and the Grey-headed Gull Chroicocephalus cirrocephalus (Figure 2) were also shown to the scholars. After about an hour the groups changed around.
Figure 9. The woven nests of weaver birds are a wonder of Nature. Using only his bill, this male Southern Masked Weaver is weaving blades of grass into the nest structure.Fig 10. A nest of the Black-winged Stilt Himantopus himantopus with eggs, as demonstrated to scholars on the nature walk.
Results
Details of educational tours made by 790 scholars from five schools, accompanied by 24 teachers, are presented in Table 2.
Scholars from the High Schools in grades 10, 11 & 12 completed questionnaires to evaluate their educational experience from the tour of the PBS/WWTW complex. The analysis in Table 3 shows the percentage responses to specific questions by grade 10 scholars.
Question
Response
Paarl Bird Sanctuary (PBS)
Would you like to have bird-related school projects?
87% definitely would
Would you like to visit PBS again soon to learn more about birds?
87% definitely would
How much did you enjoy looking at the birds?
74% replied ‘A lot.’
Waste Water Treatment Works (WWTW)
How much did you learn about water purification?
60% replied ‘A lot.’
Will what you learned at the WWTW help with your school work?
70% replied ‘A lot.’
Written comments were submitted by 55 High School scholars. A selection of these is presented as the quotations that follow.
“This place is very attractive to tourists because it has things that attract people, such as different kinds of birds, and demonstrating how water is purified.”
“This tour helped us to get knowledge about how birds are important and how water is purified.”
“I learnt a lot about birds and how water is purified, and I loved it.”
“I definitely want to visit again. Outdoors studying is more interesting. I will educate my friends about the wonderful tour we had today. I will tell my peers and family to remove waste from the water because it can seriously damage the WWTW.”
“I splendidly enjoyed being here. It gave me more interest in nature. I will always remember what I have been taught about water.”
“It was quite a mind-blowing experience and I really enjoyed it. I liked the part where we learnt about birds. There was also useful information on water purification.”
“I have learned so much from you guys. You are excellent and I hope to see you again, teaching me about birds and how to purify water. Thank you.”
“I really enjoyed this session, especially water treatment because it taught me that I must respect water.”
“All I want to say is I enjoyed the day on both sections, water purification and birds. So I just say thank you guys. I have learned a lot.”
“The WWTW was great. It helped me a lot about water purification and birds.”
“Visiting the WWTW was very exciting and interesting. I would like to visit the place often because it helps you to know what is happening in the community we live in.”
“Visiting the WWTW was very exciting and more interesting than being in class to learn what exactly is the purpose and role of natural organisms. I would like to visit this place often.”
“I have learned many different things about birds, their behaviour and how they raise their children. It was the most awesome lesson I ever had. I want to learn more about birds.”
“I enjoyed each and every moment. I learned many new things about birds and nature. It made me more curious to study about nature.”
“I found the place so beautiful and I didn’t know there is a place like this in Paarl. It has a lot of exciting activities.”
Only one girl in 790 scholars commented that she was not interested in birds or water purification.
Evaluation by teachers: eight Primary School teachers stressed the need for security protection of the PBS/WWTW complex, especially to make it safe for education. Two teachers commented on the importance of community involvement, as follows:
“This is such a valuable part of our environment. So, if we can get more schools to visit the sanctuary, people and the community will become aware of it and learn how to appreciate, respect and conserve our environment.”
“The residents of the surrounding area should be informed about the value that PBS holds for tourism, and that new job opportunities can be created. Then they must work together with PBS to fight crime.”
A comment specific to education was: “Educational tours/excursions like these expand the learners’ frame of reference and make the curriculum more ‘alive’. It also teaches them to respect and appreciate our environment, as well as to conserve our animal and plant species.”
A teacher at Desmond Mpilo Tutu High School wrote as follows: “I would like to thank you for opening up opportunities to our learners at Desmond Mpilo Tutu. They have learned a lot, and the information gathered will be used on science-related projects. We are looking forward to have more of these awareness programmes and we hope that they can improve environmental awareness in our community and promote a healthy lifestyle. This initiative will strengthen our relationship.”
Discussion
The most important result from this project has been the enthusiasm of the teachers and scholars at all the schools serving Mbekweni and Groenheuwel townships in Paarl, for information about water, birds, and biodiversity. This thirst for vital knowledge can be contagious. Based on this, it is recommended this report should be circulated for consideration and action to all administrators of education, curriculum planners, and schools in the Western Cape, and possibly throughout South Africa. Education needs to be adjusted as a matter of urgency, in order to communicate the crucial messages about the unsustainable pressure from humanity on the global and local environments, that are conveyed so clearly by birds. Wherever there are outdoor classrooms similar to the PBS/WWTW complex, these should be used as they are the most appropriate and effective venues for this essential form of environmental and health education.
A grade 10 girl reinforced this recommendation when she wrote in the evaluation questionnaire: “The out of class lesson is much better because you are taught on what you can see and I would like it to be done every week, just one day a week, so we can understand what we are taught and help us to know how birds are essential in our environment. It gave me an interest to learn more about nature and water.”
A different but equally important reaction was from a boy at a different Senior School. After he had seen the wide range of bird species in PBS he said that before the tour he had thought that doves were the only birds. This emphasises the ignorance of many urban children about nature as a whole, and the urgent need to move education outdoors as the best way to teach holistically about biodiversity and threats imposed by humanity on the survival of their own species.
The current extreme shortage of potable and irrigation water in the Western Cape, and in much of the rest of South Africa, emphasises the reality of the environmental crisis that exists. The water requirements of the human population of the Western Cape now probably exceed the fresh water resources of the province, despite storage in dams. The water crisis defines the urgency of conservation of the natural wetlands from which our water originates, throughout southern Africa.
An overall conclusion and recommendation is that humanity needs to listen to and act on the clear messages from birds and biodiversity. It is imperative that human population pressure on the environment locally in the WC and universally, must be reduced. A key to achieving this is that the reproductive rate of our species needs to slow down, so that the global human population starts to show negative growth.
Acknowledgements
Our thanks go to Senior Engineer Ronald Brown, i/c the Drakenstein WWTW, who has supported this project throughout, together with key WWTW staff members: Adam Small (Access Controller), Marshall Diederichs (Process Manager), Mteteleli Sibaca (Chemist) all of whom gave short talks to the children; Nonkululeko Tyantsi (Chief Chemist) for her encouragement; and Sandra Ontong for organisational support. The Drakenstein Municipality provided administrative and financial support (by paying for buses) through their Environmental Management Division and staff members Ilze Fiellies and Cindy Winter.
The Principals and teachers of all the schools were enthusiastic and gave us great encouragement, and as did the scholars. Mr Chris Bam, the Principal of Dalweide Primary School, was a particularly strong supporter.
Many individuals helped the children to identify birds with binoculars, some using their own spotting scopes. Those who assisted on more than one occasion were: Simon Fogarty, Yolanda Wellem, Pikkie Rousseau, Priscilla Beeton, Thembanani Magazi, Dick Barnes and Patsy Copeland. Antoinette le Roux helped specifically with Groenheuwel and Dalweide Primary Schools based on her fluency in Afrikaans and teaching experience.
Others who came to help with the school visits were Lucia Rodrigues, Ian Rijsdik, Julian Hare, Penny Dichmont, Gillian Barnes, Rose Mills and Dale Wright. Rudolph Röscher and Francis Steyn of the Western Cape Department of Agriculture introduced us to the Junior LandCare Project. Cedric Morkel introduced us to Dalweide and Groenheuwel Primary Schools. The 20 pairs of binoculars on loan from the Cape Bird Club were essential tools and a strong incentive to the children.
Funding came from the Cape Bird Club, Tygerberg Bird Club, the Western Cape Birding Forum, BirdLife South Africa Western Cape, and the Western Cape Department of Agriculture through their Junior LandCare Project.
References
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BirdLife International 2015. Decline of migratory birds wintering in Africa. African Birdlife, 3(2): 10-11.
Branch B 2008. Tortoises, Terrapins & Turtles of Africa. Struik Nature. Cape Town (see pp. 24-27).
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Predation by Southern Yellow-billed Hornbill on adult Southern Grey-headed Sparrow
Julio de Castro
34 Hedsor Drive, Harare, Zimbabwe
Lola Castro
2102 Curzon Road, Bryanston, Johannesburg, South Africa
Mabel de Castro
34 Hedsor Drive, Harare, Zimbabwe
Frank Rijnders
2102 Curzon Road, Bryanston, Johannesburg, South Africa
July 08, 2018
On 17 October 2017 we camped at Camp No. 2 at Monamodi Pan (S 25° 03’ 16.3″ E 22° 06’ 21.3″) in the Mabusehube area of the Kgalagadi Transfrontier Park, Botswana, a very dry area where food and water were scarce at the time of the visit. Birds gathered in large numbers at the few watering points available (Figure 1).
Figure 1: Doves drinking at Monamodi Pan. Photo: Julio de Castro.
The main bird visitors at our campsite were Southern Grey-headed Sparrows (Passer diffusus) but Cape Sparrows (Passer melanurus), Violet-eared Waxbills (Uraeginthus granatinus) and Sociable Weavers (Philetairus socius) were also present. Half a dozen Southern Yellow-billed Hornbills (Tockus leucomelas) were residents at the camp and were regularly seen on the ground. All bird species came to look for possible food items and water throughout the day.
On 18 November 2017 at about 10:20 am some small birds suddenly flew off where they were foraging in a response usually observed when there is (or it is perceived to be) an attack by a bird of prey. We then saw that a Southern Yellow-billed Hornbill had caught one of the adult Southern Grey-headed Sparrow and it was in the process of killing it by violently shaking it and thrashing it against the ground (Figures. 2 and 3).
Figure 2: A few seconds after the bird was caught. Photo: Frank Rijnders.
Figure 3: The Hornbill thrashing the recently caught bird. Photo: Julio de Castro.
The hornbill partially defeathered the victim on the ground before flying into a nearby tree. Here it continued to remove some more feathers by vigorously hitting and rubbing the sparrow against the tree (Figures 4 & 5).
Figure 4: The hornbill ‘plucking’ the sparrow. Photo: Julio de Castro.
Figure 5: Another view of the bird being plucked. Photo: Frank Rijnders.
It succeeded in removing most of the feathers and, at 10:53am the hornbill finally swallowed its prey (Figures. 6 & 7). The whole process lasted a little over thirty minutes.
Figure 6: The Hornbill starting to swallow the now defeathered prey. Photo: Frank Rijnders.
Figure 7: The Hornbill swallowing its prey whole. Photo: Julio de Castro.
At no time did the other sparrows or other birds attempt to mob the attacker and, after a few minutes, birds were seen again feeding on the ground at the place where the predation had taken place a few minutes earlier.
Hockey et al. (2005) cites that the Southern Yellow-billed Hornbill’s diet includes “a wide range of invertebrates and small vertebrates”. Among the latter, nestlings of Red-billed Quelea (Quelea quelea) are mentioned, together with an extensive list of prey animals. However, the list does not mention predation on adult birds.
It is possible that the observed behaviour was fortuitous. However it appears more likely that Southern Yellow-billed Hornbills take advantage of the mayhem created when large numbers of birds gather at waterholes or are distracted when foraging together to catch their prey by surprise (Figure 8).
Figure 8: Birds crowded at a water source are easy prey to predatory birds. Photo: Frank Rijnders
It could be argued that, as hornbills do not produce pellets or casts, the removal of the feathers could be connected to this fact. However, it is more likely that, together with the strong knocking of the victim against the tree, this behaviour aims at facilitating the swallowing of the prey.
References
Hockey PAR, Dean WRJ and Ryan PG 2005. Roberts – Birds of Southern Africa. The Trustees of the John Voelcker Bird Book Fund.
