Feeders and feathers and fear-scapes…oh my!

Greetings, fellow naturalists!

Karis here, with an update, the end of a journey, and the start of something new.

So much can change in a short period of time, and this year is full of the unexpected!

Just two weeks ago, armed with my backpack, camera, and a box of well-loved field guides, I bade farewell to my beloved flat in Cape Town and opened the door to a new chapter, and a new home. Though I had a few reasons to relocate, one factor heavily weighted the decision: green. I so missed having a garden, a place to live and work outdoors, and soak in the sounds, sights, and smells of the natural world.

And so it is that today, I write from the endless charm of a cottage kitchen beneath a grey and drizzly sky, thankful for the thatch-roof above my head and the mingled smells of earth and rain drifting through my window.

As I settled in through my first day in the cottage, I began to notice a few birds: Cape White-eyes calling in the trees, the liquid notes of a Southern Double-collared Sunbird spilling over from a neighbour’s garden, the shrill alarm call of an Olive Thrush. For my own amusement, I began to absent-mindedly write these down—the species name, the date, and a tick if I had seen (rather than just heard) the bird. I pinned the list to my fridge, and left it. Over the next few days, it began to grow. A Hartlaub’s Gull flew overhead. White-backed Mousebirds shared dust-baths in the sand, and a Red-eyed Dove (which sounded as though it was singing IN my ear) startled and burst into song at 04h30 in the morning.

The interest continued to increase when I mentioned the list to my landlords; they were excited by the prospect of having a bird list for the property, and gave me free rein to make the garden more bird-friendly! By this point, I was thoroughly invested—I had been keen to try my hand at maintaining an indigenous garden, and this was the perfect excuse to do so. That same day, I contacted Communitree, a brilliant urban-greening organisation based in Cape Town. Communitree answered my questions and matched my enthusiasm, and I delved into the process of dreaming and scheming a design which will incorporate as many native species as possible, whilst also attracting a wide variety of insects and birds.

Though promising, this level of transformation takes time, and I wanted something to “do” in the interim. So, I enlisted the aid of my doctoral supervisor, Les Underhill, and he responded in the form of two bird feeders, on conditional loan: I could use the feeders so long as I collected observational data and turned it into writing! I readily accepted the offer, and am keen to keep up my end of the bargain. After some deliberation, we decided on the following very basic protocol:

-2 feeders, one surrounded by open space, and one close to a shrub, hedge, or tree,

-2 10-minute bird counts conducted at set times in the morning and afternoon, and a series of 10-minute counts scattered throughout the day, with 30-minute breaks between observation periods.

These simple counts will provide surprisingly rich information. First, the position of the feeders is significant. Les has noticed (as those of you who regularly feed birds in your garden may also know) that one of his feeders consistently attracts more birds. Though many factors likely play into this reality, one is of particular interest; the “busy” feeder hangs from a tree, affording visitors a quick and easy escape either further into the tree or into the nearby bushes, while the less popular feeder stands in the open. This addresses a phenomenon within behavioural ecology called the “landscape of fear.”

This model contends that species which are often predated modify their behaviour within a habitat based on where they perceive themselves to be at the greatest risk of predation. For instance, returning to our bird feeder example, let’s imagine a Cape Sparrow who has a choice between two garden feeders: Feeder 1, a crowded spot next to a shrub, or Feeder 2, a quiet feeder in the middle of the garden. Even though the quality of food at both feeders is identical, whichever feeder our sparrow chooses requires a sort of trade-off. 

If he chooses Feeder 1, he can easily escape from predators, but has to compete with several other birds for food—that takes energy. If he chooses Feeder 2, he no longer has to compete for food, but is at a greater risk of being spotted and snatched by a predator before he can retreat.

Placing one feeder in each location and monitoring which attracts how many birds, of what species, and when can spark thought-provoking questions into the other factors playing into how each bird makes its foraging gamble. Are some sparrows “bolder” than others, and more likely to engage in risky behaviour? Does that risky behaviour pay off, or are “bold” birds more likely to be eaten? Are species which forage in groups more likely to visit a risky, exposed feeder? Does foraging in a group actually reduce the risk of predation? What about visibility? Will some birds engage in riskier behaviour when visibility is poor, and they have a lower chance of being spotted by a predator? These are a just a few examples—there are SO many questions we can ask based only on where we place a bird feeder in the garden!

Feeders are also great opportunities to look at inter-species interactions—which birds are territorial around the feeder (another energy-costly behaviour!) and when? Are male birds more likely than females to be territorial, or vice versa? Does behaviour change seasonally? Though many of these questions have seemingly intuitive answers, they may still bring a few surprises!

Here’s a challenge for all you garden birders: spend 10 minutes each day with a notebook and a pencil watching birds in your garden, and simply write things down as you notice them. Do you notice the number and diversity of species? Do you notice variations in plumage? Or behaviours and interactions? Try this for a week or two, and then review your notes, paying close attention to what you noticed. This is a simple trick for learning what you are curious about. Once you have an idea that interests you, put that curiosity to use! Make a spreadsheet to track the species in your garden each day. Take photos of birds in moult or with unusual markings (and submit them to BOP on the Virtual Museum!). Choose one or two species to focus on, and use an ethogram to keep a detailed account of the behaviours you observe in a thirty-minute block of time. Check out the “Birds” section in this resource from the Royal Zoological Society of Scotland for a few tips on creating an ethogram.

For a simulation of foraging ecology, check out this link. The model allows you to experiment with how predation survival changes when birds forage in groups versus individually.

In addition to generating some interesting ecological ponderings, conducting counts is a great way of monitoring changes in local species composition and phenology over time. What birds are active in the morning? What birds are active day-long? What birds are present for only a few months of the year? What species are moulting, and when? Something as simple as two or three daily counts (and a few photographs for BirdPix) can provide a detailed picture of the species and traits which are most prevalent in a given place at a given time, again, paving the way for more complex and nuanced questions of seasonality, movement, and range.

Well, this has been a very long-winded way of saying…

  1. Gardens are a great place to study ecological principles, and
  2. You can start your own study at home!

I will be checking in every few months or so with an update on my garden situation, and in the meantime, I would love to hear your stories! Have you already noticed interesting patterns, behaviours, or changes at your garden feeders? What questions arise from your observations? Comment on this post or send an email to get in touch. We may even include one or two interesting stories in a future issue of the BDI Bridge.

Happy exploring!

Karis

Further reading on the ecology of fear (this is the article that started it all):

The Ecology of Fear: Optimal Foraging, Game Theory, and Trophic Interactions

Joel S. Brown, John W. Laundré, & Mahesh Gurung,

BDInsight – March 2021

March has marched right past! And we are heading into the Easter holidays. We wish you all a wonderful Easter Weekend full of BioMAPping adventures!

Read on for the latest BDI News….

OdonataMAP – Vital Odonata Areas

One of the main things we have been working on behind the scenes, is determining Vital Odonata Areas for South Africa. In other words, areas of conservation priority for dragonflies and damselflies across South Africa.

The selection of sites of special importance to biodiversity conservation is traditionally qualitative, or at best semi-quantitative. For example, the guidelines for the selection of Important Bird Areas (Grimmett & Jones 1989) contain statements such as “The site is known or thought regularly to hold significant numbers of a globally threatened species” (BirdLife International 2021). This is a criterion that can be challenged in several ways on quantitative grounds; for example, the terms “regularly” and “significant numbers” are left undefined, and the criterion becomes thus open to interpretation in multiple ways. This is an expert-driven approach (O’Dea et al. 2006)

A quantitative approach of conservation site selection has aimed to obtain the smallest set of sites which included all species in at least one of them (Margules et al. 1988, Vane-Wright et al. 1991, Pressey et al. 1993). The initial algorithms employed for the “reserve selection problem” used a heuristic procedure known as the “greedy algorithm” and these were shown to be sub-optimal (Underhill 1994); they were replaced by linear programming tools that provide optimal solutions using readily available software (Rodrigues & Gaston 2002). There are many variations of the theme.

However, the reserve selection problem differs from the Important-Bird-Areas approach. The first is an algorithm, the second consists of expert opinion. The sites selected by the two approaches can differ radically (O’Dea et al. 2006). One of the assumptions of the quantitative approach is that it species distribution database is complete, and in particular that there are no false negatives, places where the species occurs, but where it has not been recorded. The main problem effectively highlighted by O’Dea et al. (2006) is that the experts cannot hold all the alternative combinations of potential sites in mind at once. However, they are able to consider the smorgasbord of other factors that are part of site selection, and not only species distribution.

The approach proposed by the BDI and the Freshwater Research Centre aims to overcome three issues: (1) It makes use of “complete” distribution maps which are created by the algorithm of Underhill (in prep.) to generate maps from patchy data using imputing approaches; (2) It uses an algorithm to select a set of candidate sites (and to rank them), ensuring that no site is overlooked; (3) This relatively small number of ranked candidate sites, and the species that the algorithm believes occur there, are presented to an expert panel, who can examine them for feasibility.  

More on this soon! So watch this space! 🙂

The AB and the ABC: Action in the Baltic, and the April Bulbul Challenge!

On Tuesday, the 30th of March 2021, we had a great session, a Citizen Scientist Hour about birds! Thank you very much to all for attending and special thanks to the speakers.

The videos are now on the BDI YouTube channel, so you can enjoy the talks again, or watch them for the first time if you missed them:

Two amazing journeys: Rwanda and Nigeria!

On the 25th of March we had two amazing talks, one from a journey to a beautiful National Park in Rwanda, and the other about the journey of the Nigerian Bird Atlas Project. We these two talks we celebrated that the milestone of 100 videos on our YouTube Channel:

BirdPix on a run in 2021

BirdPix is important because it is going to be used to test whether “species distribution models” can be used to generate maps that look like the bird atlas maps from SABAP2. If we can get this right for the birds, then we can use the same statistical models for the dragonflies, the reptiles, the butterflies and everything else. It is only for birds that we can compile species lists for a place which are pretty comprehensive and complete within a few hours.

For example, for reptiles, good species lists for a locality are tough to get. There is a fascinating section in the reptile atlas for South Africa, Lesotho and eSwatini that describes 22 surveys, each at least 10 days long, which attempted to find all the reptiles at a site. See section 3.3.1 (pp. 4-6) in the reptile atlas for a description of all the search methods used, such as road-cruising at night, searching through leaf-litter, under rocks and sheets of corrugated iron, massive “trap arrays”, night-time spotlight surveys for sleeping chameleons, etc. And after 270 days of fieldwork, there was good data for 22 grid cells, out of more than 2000! So the maps in the reptile atlas (and in ReptileMAP in the Virtual Museum with another eight years of data) are full of holes. Here is the distribution map for the Cape Cobra:

ReptileMAP distribution map for the Cape Cobra (6 March 2021). Light green quarter degree grid cells have Virtual Museum (ie photographic records (348 of them), and the darker green cells have only specimen records (for a total of 509 records from 315 grid cells). The four red records were deemed questionable by the authors of the reptile atlas. The broad pattern is clear. Cape Cobras occur in the west! There are 100s of grid cells in which it MUST occur, but there are no records, either in the historical data, or in the Virtual Museum data! The Cape Cobra inset at the top of the map is the only record in what would otherwise be a big gap along the West Coast (http://vmus.adu.org.za/?vm=ReptileMAP-159677).

Obviously, and sadly, this map for the Cape Cobra is stuffed full of “false negatives”. These are grid cells in which the species occurs, but in which it has never been recorded. Remember that this map is built with the reptile atlas as the base, so it includes all the museum specimens and literature records as well as the Virtual Museum records.

“Species distribution models” provide a statistical approach to dealing with this problem. They use an objective approach to filling in the gaps (which is better than just doing it “by eye”, which is the strategy used for the fieldguides!). There are dozens and dozens of models, which all give different answers. How do you tell which species distribution models work well? The answer is simple. You need to have maps which are the truth. And the bird atlas provides this. So if we can use the BirdPix data (which is still even scruffier and even fuller of false negatives than the the ReptileMAP data) to “model” the bird atlas data, we can test the various species distribution modelling techniques.

The BirdPix database is still a good deal smaller than those of LepiMAP, ReptileMAP, etc. So, without neglecting all the other groups of species in the Virtual Museum, we want to give BirdPix a boost in 2021. The maps below show how well we are doing. The red and yellow maps show how well we are doing overall, and the blue maps show how well we are doing in 2021. The numbers in the quarter degree grid cells in the red-yellow maps show the total number of species for each grid cell. The numbers in the blue maps show the number of species based on records submitted in 2021 (so this does include some older records, but this is an incentive to get recognition for submitting your old records!!).

We’ll start in KwaZulu-Natal, and go roughly clockwise through the provinces of South Africa (ie KwaZulu-Natal, then Eastern, Western and Northern Capes, North West, Free State, Limpopo, and finally Mpumalanga and Gauteng. For each province, the cumulative red-yellow map comes first, then the blue map for 2021. The explanation for the KwaZulu-Natal maps is detailed, so you should probably read this, and then skip straight to the province that interests you the most.

Overall, KwaZulu-Natal has BirdPix records from 155 of the 174 quarter degree grid cells that intersect with the province. 15 of the 19 with no records are easy to spot. The other four just have slivers in the province and are a challenge to find! The 27,176 records which have been identified to species have yielded 612 species. The number in a grid cells is the species richness of the grid cell. If you add the numbers of species in all the grid cells in this map, the total is 9,685. You can say 9,685 species-grid cells. Another way to think of this number is compiling a distribution map for each of the 612 species. The total number of grid cells which would be shaded is 9,685. If every species occurred in every grid cell, then the number of shaded grid cells would 612×174=106,488 species-grid cells. The truth is much less than this, but much more than the current 9,685!

For every one of the 155 grid cells with data, we have calculated the most recent date on which each species was recorded. We have sorted these, and chosen the middle date (which is officially called the median). This measures the “average age” of the data for the grid cell. Obviously we’d love every species to be represented by a recent record. This confirms that the species still persists there. We end up with a collection of 155 medians. To get a quick summary of them, we repeat the process. Sort them. Find the date in the middle. This provides a measure of the “up-to-dateness” of the BirdPix data for KwaZulu-Natal. The median of the medians for KwaZulu-Natal is 28 December 2017. That is 39 months ago. For half the grid cells, half the species were seen after 28 December 2017, and vice versa. That is the interpretation of this date. We can improve this date by replacing old records of a species in a grid cell with new ones. We call this refreshing the data.

That leads us to the next map, the blue one:

The blue maps use only records submitted in this year, 2021. The number in each grid cell is the number of species submitted for that grid cell since 1 January 2021. If we can make this blue map really good during 2021, then lots of species will have records in 2021, and this will drag the “up-to-dateness” closer to the present! 80 grid cells have been visited so far in 2021. The total of these 80 numbers is 1,709. In these 80 grid cells, the most recent record for 1,709 species has moved to 2021. The median date in these 80 grid cells has changed for the better. And this must pull the overall median closer to the present.

The Eastern Cape has BirdPix records from 238 of the 314 quarter degree grid cells that intersect with the province. 12,271 records have been identified to species. They have yielded 552 species. If you add the numbers of species in all the grid cells in this map, the total is 6,776 species-grid cells. The up-to-dateness of BirdPix in the Eastern Cape is 2 November 2017. That is 40 months ago. We can improve this date by replacing old records of a species in a grid cell with new ones. We need to keep refreshing the data.

The blue map shows that 87 grid cells in the Eastern Cape have been visited so far in 2021. The total of the numbers of species in these 87 grid cells is 1,121 species-grid cells. The median dates in these 87 grid cells have changed for the better. This is the strategy to improve the up-to-dateness of the data. Get records for as many species as possible in 2021. 

The Western Cape has BirdPix records from 226 of the 263 quarter degree grid cells that intersect with the province. 35,391 records have been identified to species. They have yielded 465 species. If you add the numbers of species in all the grid cells in this map, the total is 11,676 species-grid cells. The up-to-dateness of BirdPix in the Western Cape is 24 August 2019. That is 19 months ago. That’s excellent. To maintain this relatively recent date we are going to need to keep replacing old records of a species in a grid cell with new ones. We need to keep refreshing the data.

The blue map shows that 106 grid cells in the Western Cape have been visited so far in 2021. The total of the numbers of species in these 106 grid cells is 2,278 species-grid cells. The median dates in these 106 grid cells have changed for the better. This is the strategy to maintain the up-to-dateness of the data. Get records for as many species as possible in 2021. 

The Northern Cape has BirdPix records from 412 of the 654 quarter degree grid cells that intersect with the province. 15,327 records have been identified to species. They have yielded 412 species. If you add the numbers of species in all the grid cells in this map, the total is 8,486 species-grid cells. The up-to-dateness of BirdPix in the Northern Cape is 18 January 2019. That is 26 months ago. For a large and difficult province, this is remarkably good. To maintain this we are going to need to keep replacing old records of a species in a grid cell with new ones. There are 242 grid cells with no records at all. We need to try to reach these too!

The blue map shows that 90 grid cells in the Northern Cape have been visited so far in 2021. The total of the numbers of species in these 90 grid cells is 842 species-grid cells. The median dates in these 90 grid cells have changed for the better. This is the strategy to maintain the up-to-dateness of the data. Get records for as many species as possible in 2021 (and visiting new grid cells also helps!). 

North West has BirdPix records from 113 of the 202 quarter degree grid cells that intersect with the province. 14,247 records have been identified to species. They have yielded 473 species. If you add the numbers of species in all the grid cells in this map, the total is 5,430 species-grid cells. The up-to-dateness of BirdPix in North West is 24 February 2017. That is 49 months ago. We can improve this date by replacing old records of a species in a grid cell with new ones. We need to keep refreshing the data.

The blue map shows that 43 grid cells in North West have been visited so far in 2021. The total of the numbers of species in these 40 grid cells is 859 species-grid cells. The median dates in these 43 grid cells have changed for the better. This is the strategy to improve the up-to-dateness of the data for North West. Get records for as many species as possible in 2021. 

The Free State has BirdPix records from 176 of the 238 quarter degree grid cells that intersect with the province. 7,424 records have been identified to species. They have yielded 429 species. If you add the numbers of species in all the grid cells in this map, the total is 3,811 species-grid cells. The up-to-dateness of BirdPix in the Free State is 3 February 2018. That is 38 months ago. We can improve this date by replacing old records of a species in a grid cell with new ones. We need to keep refreshing the data.

The blue map shows that 66 grid cells in the Free State have been visited so far in 2021. The total of the numbers of species in these 66 grid cells is 847 species-grid cells. The median dates in these 66 grid cells have changed for the better. This is the strategy to improve the up-to-dateness of the data for the Free State. Get records for as many species as possible in 2021. 

Limpopo has BirdPix records from 168 of the 221 quarter degree grid cells that intersect with the province. 14,670 records have been identified to species. They have yielded 561 species. If you add the numbers of species in all the grid cells in this map, the total is 6,790 species-grid cells. The up-to-dateness of BirdPix in Limpopo is 16 June 2016. That is 57 months ago, almost five years. We need a concerted effort in Limpopo to replace old records of a species in a grid cell with new ones.

The blue map shows that 31 grid cells in Limpopo have been visited so far in 2021. The total of the numbers of species in these 31 grid cells is 656 species-grid cells. The median dates in these 31 grid cells have changed for the better. This is the strategy to improve the up-to-dateness of data for the Limpopo. A special effort is needed to get Limpopo up-to-date. 

Mpumalanga has BirdPix records from 140 of the 157 quarter degree grid cells that intersect with the province. 11,892 records have been identified to species. They have yielded 547 species. If you add the numbers of species in all the grid cells in this map, the total is 5,325 species-grid cells. The up-to-dateness of BirdPix in Mpumalanga is 14 January 2017. That is 50 months ago. We can improve this date by replacing old records of a species in a grid cell with new ones. We need to keep refreshing the data.

Gauteng has BirdPix records from all 47 of the quarter degree grid cells that intersect with the province. 17,993 records have been identified to species. They have yielded 491 species. If you add the numbers of species in all the grid cells in this map, the total is 4,129 species-grid cells. The up-to-dateness of BirdPix in Gauteng is 23 August 2017. That is 43 months ago. We can improve this date by replacing old records of a species in a grid cell with new ones. We need to keep refreshing the data.

The blue map shows that 42 grid cells in Mpumalanga have been visited so far in 2021. The total of the numbers of species in these 42 grid cells is 535 species-grid cells. The median dates in these 42 grid cells have changed for the better. This is the strategy to improve the up-to-dateness of the data for Mpumalanga. A big drive is needed to get records for as many species as possible in this province in 2021

The blue map shows that only 27 of the 47 grid cells in Gauteng have been visited so far in 2021. The total of the numbers of species in these 27 grid cells is 458 species-grid cells. The median dates in these 27 grid cells have changed for the better. This is the strategy to improve the up-to-dateness of the data for Gauteng. A big drive is needed to get records for as many species as possible in this province in 2021.

How do you refresh a butterfly? You LepiMAP it in 2021!

The take home message of this blog is one of disappointment! But the reality is that we have never looked at the butterflies in LepiMAP in this way before. Because we have never been aware of how disappointing it is, we (= project coordinators) have not been encouraging corrective action. So the sense of disappointment is directed at ourselves, and not at the citizen scientists who are LepiMAPpers!

We have just invented ways to measure the “age” of the data for a project. There is a long explanation in an OdonataMAP blog and there is a video that covers the same ground in the BDI YouTube channel.

In a nutshell, choose a quarter degree grid cell in a region of interest. Find the most recent date on which each species was recorded, sort these dates, and pick the middle (the median). This gives an estimate of the “age” of the data for that grid cell. Find the median for every grid cell in the region. Find the median of all the medians. This is a good handle on the “age” of the data in the region. It is quite a challenge to wrap the brain around what this date means, but once you have got it, it’s easy. This median of the medians is the mid-date of the records in half the grid cells!

Would you like to hazard a guess what this date is for the butterflies in LepiMAP? Remember that the butterflies were last given a concerted refreshment drive during the SABCA project (fieldwork finished 2010, in South Africa, Lesotho and eSwatini). Even worse is to bear in mind that 90% of the SABCA data was specimen data, digitized from museums and private collections. Many records go back to the early part of the 20th century, and some to the 19th! A lot of species have not been “refreshed” since they were first recorded. It sounds like I am psyching you up for a really bleak picture.

It is hard to know whether the answer is “good” or “bad”, because we have never done these calculations before. The median of the medians for the LepiMAP data for South Africa, Lesotho and eSwatini is 1 March 2003. So in February 2021, it is almost exactly 18 years old. In broad brush terms, half the records in half the grid cells were made before that date, and half afterwards.

The problem with data getting long-in-the-tooth is that the distribution maps we produce can no longer really be claimed to be up-to-date! It would be nice to produce distribution maps using data from only the past decade, say. But they would look very sparse. We have never really thought in these categories before! But in an era of rapid development and climate change, old records do not provide evidence that a species still occurs in a grid cell. Ideally, it would be nice to make distribution maps using records from just the past five years!

Sharon Stanton and Heleen Louw “refreshed” this Lysander Opal Chrysoritis pan lysander on 6 February 2021. The previous record of this species in the Nuy quarter degree grid cell (3319DA), near Worcester, Western Cape, was on 18 October 1967. Gosh, that is 53 years ago. The record is archived at http://vmus.adu.org.za/?vm=LepiMAP-737335

So we need to make a determined effort to “refresh” records, and nudge that median of the medians in the direction of now!

How do we do this? Autumn is around the corner. With it comes a big peak in butterfly abundance. So plan to make a big effort to refresh records over the next few months! Start with the grid cells close to you. The secret is to upload every record you can. If we can refresh all the common species in the well-covered grid cells, that will make an awesome start.

Try to visit your favourite sites this autumn. In the past, our mindset has largely been on adding species not yet on the list for the grid cell. Now, the approach needs to be to aim to refresh everything!

The maps below provide some sort of context. The red-yellow maps for the provinces of South Africa provide the long-term overview, and give the total number of butterfly species in the LepiMAP database per grid cell. The harsh reality is that in all provinces there is lots of fieldwork to be done, and this big picture stuff must not be forgotten in the drive to refresh records! The blue maps are the scary ones. They show the number of butterfly species per grid cell so far in the current butterfly year, taken as starting on 1 July 2020. We are just over seven months into that year, with the best months just ahead. So we have still the opportunity to redeem ourselves!

We’ll work clockwork round the provinces. In the previous blog, we started in Limpopo and ended in North West. This time we’ll begin in the Western Cape, followed by Northern Cape, Free State, North West, Limpopo, Mpumalanga and Gauteng, KwaZulu-Natal and ending in the Eastern Cape.

Western Cape

The quick summary for LepiMAP butterflies in the Western Cape runs like this: 351 species recorded; 54,754 records identified (IDed) to species (or subspecies); 6,786 species-grid cells***; 240 out of 263 grid cells have data (this excludes the three shown as 0 in the map – these have records, but could only be IDed to genus). The median of the medians in the Western Cape is 13 November 1996. In other words, there is a huge amount of historical data that has never been refreshed. The message here is simple, and does not need to be put into words of one syllable! [*** 6,786 is the total you get when you add together all the numbers in the map above; it is the sum of the species richness number in all the grid cells, so we call it the species-grid cell number!]

This is the Western Cape since 1 July last year. Lots of grid cells have just a few species. A handful are in the twenties! Lots of opportunities everywhere to help bring the median dates for grid cells closer to the present!

Northern Cape

This is the overall summary for LepiMAP butterflies in the Northern Cape: 249 species recorded; 19,302 records IDed to species (or subspecies); 4,810 species-grid cells (the sum of the numbers in the map); 431 out of 654 grid cells in the Northern Cape have records IDed to (sub)species. The median of the medians in the Northern Cape is 27 September 2008. The Northern Cape is 12 years ahead of the Western Cape; a determined effort to collect data was made in the Northern Cape during the SABCA period.

This is the species richness per grid cell in the Northern Cape since July last year. If you can plan a trip there this autumn, especially to the areas which have had rain recently, you can make an enormous difference to this map.

Free State

This is the overall summary for LepiMAP butterflies in the Free State: 278 species recorded; 12,472 records IDed to species (or subspecies); 3,405 species-grid cells (the sum of the numbers in the map); 204 out of 238 grid cells in the Free State have records IDed to (sub)species. The median of the medians in the Free State is 28 January 1997, essentially the same as the Western Cape. There’s a handful of grid cells with impressive species richness. The biggest thing that these grid cells achieve is to highlight what ought to be feasible in the grid cells with very thin coverage.

The only thing needed to achieve a drastic improvement in the “age” of the data in Free State is to visit a lot of grid cells, and get a few records from each. When only a handful of species have been recorded in a grid cell, it is easy to bring the median of last records of species right up to the date of fieldwork!

We hope that a big effort is feasible in the Free State this autumn.

North West

This is the overall summary for LepiMAP butterflies in the North West: 259 species recorded; 18,569 records IDed to species (or subspecies); 4,126 species-grid cells (the sum of the numbers in the map); 157 out of 202 grid cells in the North West have records IDed to (sub)species. The median of the medians in the North West is 30 January 2010, so the data can be described as reasonably up-to-date. The priority here is that it is rather thin, especially in the western two-thirds of the province!

Please go west in North West!

Limpopo

Here is the overview for LepiMAP butterflies in Limpopo: 454 species recorded; 71,373 records IDed to species (or subspecies); 13,471 species-grid cells (the sum of the numbers in the map); only five grid cells entirely inside Limpopo have no data, out of 221 grid cells. The median of the medians in Limpopo is 1 November 2008.

Compared to the the long-term coverage map, LepiMAPping in Limpopo since July last year has been quite sparse. There’s an opportunity to make a big improvement this autumn!

Mpumalanga and Gauteng

Gauteng is in the western edge. Mpumalanga is across the centre and the east.

This is the overall summary for LepiMAP butterflies in the Mpumalanga: 442 species recorded; 44,809 records IDed to species (or subspecies); 9,176 species-grid cells (the sum of the numbers in the map); Mpumalanga touches 157 grid cells. Only two grid cells falling entirely within the province have no data, and there is another half a grid cell sharded the Free State withoug data. The median of the medians in the Mpumalanga is 4 December 2007

The overall summary for LepiMAP butterflies in Gauteng shows 263 species recorded. 30,715 records have been IDed to species (or subspecies). There are 3,777 species-grid cells (the sum of the numbers in the map). Every one of the 47 grid cells in Gauteng have records IDed to (sub)species. The median of the medians in Gauteng is 8 January 2009.

This is the map of species richness in Mpumalanga and Gauteng since July last year. The southwestern corner of Gauteng badly needs attention and there is plenty of scope for big improvements in northwest. No matter where you go in Mpumalanga, you will make a substantive contribution. There is lots of potential for autumn fieldwork in the next few months!

KwaZulu-Natal

This is the overall summary for LepiMAP butterflies in KwaZulu-Natal: 489 species recorded; 189,921 records IDed to species (or subspecies); 16,269 species-grid cells (the sum of the numbers in the map); only one of the 174 grid cells in KwaZulu-Natal has no records IDed to (sub)species (and this is in the far south, and most of the grid cell is in the Eastern Cape! In spite of the wealth of data, the median of the medians in KwaZulu-Natal is 28 September 1994, getting on for three decades ago. In inescapable conclusion is that the KwaZulu-Natal data is getting a bit long in the tooth!

The pattern of LepiMAPping in KwaZulu-Natal is for a handful of grid cells to be done superbly well every year. It is easy to pick these out on the map! This is incredibly valuable data, because it will enable amazing analyses of long term trends and how phenology*** is changing through time. There are PhDs lurking in that part of the database, and we encourage the LepiMAPpers in these grid cells to keep on keeping on. But we really badly need some mobile LepiMAPpers to visit lots of different grid cells. To achieve a large shift to the medians in many of the grid cells will need quite intensive fieldwork, because the species richness in the grid cell is substantial. Getting the KwaZulu-Natal data up-to-date represents a really big challenge! (*** In this context, the “phenology” of a butterfly species means the period when adults are in flight.)

Eastern Cape

In the Eastern Cape, the quick summary for LepiMAP butterflies runs like this: 445 species recorded; 43,447 records IDed to species (or subspecies); 8,245 species-grid cells (the sum of the numbers in the map); 288 out of 314 grid cells in the Eastern Cape have records IDed to (sub)species. The median of the medians in the Eastern Province is 27 November 1988. In a nutshell, the coverage is great, but age is an issue.

… this autumn, aim for the interior of the Eastern Cape.

… this is only part of “quality”

This blog has focused on one aspect of the quality of biodiversity data, and that is “up-to-dateness”. There are lots of other dimensions of quality. Spatial quality is important too. It is quite hard to measure; the obvious coverage statistic is the percentage of grid cells with data, but we really need something more subtle which takes account of whether the data is well-scattered through the region, or whether it is concentrated in just one part of the region.

For butterflies, we would also like to have the data well scattered in time through the overall flight period, so we have a good chance of recording the species that only fly for a short period in the season. So we need a measure of seasonal quality.

We don’t only want up-to-date data, old data is also important, because it is critical for detecting expansions and contractions in distributions. It is especially valuable to have a sample of grid cells which get a lot of records, consistently, every year. So we need a measure of long-term data quality. If this dimension of quality for a region is good, then it means that the data is likely to be valuable for looking for range changes through time.

But for autumn 2021, let us focus on bringing the data in the grid cells within our reach up-to-date. No one has to do everything or be everywhere. Citizen science is about teamwork, and if we all do what we are able to do in our areas, then cumulatively we can make a big difference. Perhaps not in a single autumn, but if we keep this new mindset working into the next few years, then we will see huge changes.

As the leadership of LepiMAP (and the Virtual Museum in general), we ought to have done this important thinking years ago, and we are sorry that we didn’t. On the other hand, no other projects seem to have done any quantitative thinking along these lines, so the Virtual Museum retains global leadership in this area.

Acknowledgements

Rene Navarro developed the software used for these brand new measures up-to-dateness. Karis Daniel generated the maps.

There would not be anything to write about without the contributions of Team LepiMAP. Thank you for your support.

BDInsight – January 2021

The first month of the new year is already behind us! For January 2021 BioMAPpers managed to snap and map almost 10,000 records on biodiversity. Amazingly well done!

Starting from scratch…

OdonataMAPpers in KwaZulu-Natal have started 2021 from scratch. They have taken on board the New Year’s resolution for Team Virtual Museum! “Starting in my home grid cell on 1 January 2021, I will upload records to the Virtual Museum of as many species as possible (and I will be especially careful not to neglect the common species). Wherever I travel in 2021, I will do my best to keep the distribution maps up-to-date for as many species as possible.”

This is what Team KZN has achieved halfway through the first month of 2021 for OdonataMAP. By taking this approach we are keeping the records fresh, and this is especially important for the common species, which we tend to neglect.

This map is based on records uploaded in 2021 by 17 January and identified by the expert panel. The numbers in the grid cells represent species richness by this date

BDI Citizen Scientist Hours

BDI Citizen Scientist Hour #20 was held on Thursday 28 January 2021. We had two great talks lined up for the evening. These were:

  • Karis Daniel: “It takes a village: Why biodiversity needs citizen scientists and their data”

Karis, a recent PhD candidate at UCT, shared the reasoning behind her current research, exploring how Citizen Science as a discipline not only contributes to scientific research, but also plays a key role in creating long-term conservationist attitudes and lifestyles in broader communities.

Climate is changing throughout the World, but there are marked regional differences in the pace of this change, in the impacts, the intensity of research, and the amount of biodiversity at risk. David talked about the information they have synthesized from hundreds of studies worldwide to determine the upper thermal limits of ectotherms, and the extent to which they could be endangered by rising temperatures in hot versus cool regions.

On Wednesday 20th January 2021, the BDI Citizen Scientist Hour had another two awesome talks for the evening.

Melissa, who is BirdLife SA’s Landscape Conservation Programme Manager, shared insights about South Africa’s Secretarybirds and how citizen science is assisting with monitoring these Endangered sentinels of the grasslands and open landscapes.

  • Les Underhill: “The Virtual Museum: achievements of 2020 and plans for 2021”

Les reviewed the record-breaking year which the Virtual Museum achieved in 2020 and he set some targets for 2021. The main goal for the year is to keep the distribution maps up-to-date by continually refreshing records of species in grid cells. He will introduced us to new ways of measuring up-to-dateness.

You can catch up on all the various talks on our YouTube Channel!

The Fundamentals of Citizen Science – A BDI Course

We believe that citizen scientists can make a significant contribution towards healing the massive biodiversity issues of our generation. On one hand, citizen scientists enable up-to-date distribution maps for species to be made. On the other hand, citizen scientists generate civic awareness for biodiversity in their communities, becoming “ambassadors for biodiversity.” You can be a part of this by attending the BDI’s week-long Fundamentals of Citizen Science course.

We plan to run the course multiple times in 2021, at different venues. Provisionally (but with accommodation booked at the three places), these dates have been selected: 21–28 February at Karoo Gariep Nature Reserve, Hanover; 11–18 April at Karoo Plains, Carnarvon; 6–13 August at Botuin, Vanrhynsdorp.

How do you apply? Start by sending an email to Megan at megan@thebdi.org

Starting from scratch : OdonataMAP in 2021

Cherry-eye Sprite. Jaco Botes

We lost all the data***. Now we need to be starting from scratch!

This is not such a crazy idea. It is so easy to think. I know that the Red-veined Dropwing has been recorded here. I won’t bother to take a photograph of that dropwing, even though it is sitting so beautifully over there, because I know someone has submitted it already.

Full marks to Andries and Joey de Vries! On 1 January 2021, they anticipated this blog by photographing, and uploading, one of the species that is so readily ignored because it is so common, the Red-veined Dropwing! This record is curated at http://vmus.adu.org.za/?vm=OdonataMAP-102592

If we taken this approach, then, as the years tick by, the database steadily gets to show its age. The distribution maps we produce for a species tend to be based on older and older records.

How can we measure the “age” of the OdonataMAP data for, say, South Africa, Lesotho and eSwatini? Here is a recipe, with four steps. (1) In each quarter degree grid cell, find the date of the latest record of each species. (2) Sort these dates and find the date in the middle (the statistician’s median). Half the species in the grid cell have been seen before this date, and half after. We want this date to be as recent as feasible. Because we are taking the date in the middle, the fact that some species were recorded as vagrants a century ago does not influence the “middle date”. (If we had used the “average date”, the very old dates would drag the answer back in time in a way that is not OK. The mean of 1920, 2005, 2015 is 1980, but the median, the date in the middle is 2005.) (3) Find the “middle dates” for all the grid cells with records in South Africa, Lesotho and eSwatini. (4) Sort all these dates, and find the date in the middle. This median of the medians measures the “age” of the data for this region. In half of the grid cells, half the species have been seen since this date. (Here is a video that presents the same ideas; it is in the BDI YouTube channel.)

How far in the past is this median of the medians? Right now, on 1 February 2021, this date is 16 December 2015. This is the median of the medians for all grid cells with OdonataMAP data in South Africa, Lesotho and eSwatini. That is 5 years and a month ago. In English, this means that in half of the grid cells with records, half of the species have been recorded in the past five year, and half are older than that.

Five years is getting near the limit. Once the most recent record of a species in a grid cell gets to be five years old, it cannot really be used as evidence in a law court that the species persists there. In a nutshell, the OdonataMAP data is just starting to get a bit long in the tooth, and we need to make a special effort, starting in 2021, to pull it up to date.

I have a real soft spot for the Cherry-eye Sprite. When you look at it, it is a 100% appropriate name for this damselfly. Whoever dreamt up this name deserves a medal. This was one of about a hundred records of dragonflies and damselflies made on 1 January 2021. This photo, taken by citizen scientist Jaco Botes is curated for posterity at http://vmus.adu.org.za/?vm=OdonataMAP-102859

The best strategy for doing this is simply to act as if we need to start all over again. We especially need to focus on the common species! A great start was made on 1 January 2021, and this blog is illustrated with a few of the records collectedon this date. What follows is a set of maps, for the provinces of South Africa, which shows the number of species per grid cell, uploaded in the 29 days of 2021 AND identified to species level by the awesome OdonataMAP expert panel.

We start in the north, with Limpopo, and work our clockwise: Mpumalanga and Gauteng, KwaZulu-Natal, Eastern Cape, Western Cape, Northern Cape, Free State, and finally North West Province. On one hand, these maps show how much has been attained in only a month. On the other hand, they show how much there is to do!

[*** … of course we haven’t lost the data … but let’s work as if this is the truth!]

These are the grid cells in Limpopo with records uploaded in 2021. On 1 February 2021, for Limpopo overall, using the entire database, the the median of the medians was 6 March 2014. Half the records in half of the 170 grid cells with records are older than this. This means that the average age of the OdonataMAP data for Limpopo is 6 years 11 months, 21 months behind the average for the region!

These are the grid cells in Mpumalanga and Gauteng with records uploaded in 2021 so far.

On 1 February 2021, for Mpumalanga as a whole, the median of the medians was 29 August 2014. Half the records in half of the 128 grid cells with records are older than this. This means that the average age of the OdonataMAP data for Mpumalanga is 6 years 5 months, 16 months behind the average for the region!

For Gauteng, the median of the medians was 4 February 2016. Half the records in half of the 42 grid cells with records are older than this. This means that the average age of the OdonataMAP data for Gauteng is almost exactly 5 years. So Gauteng is one month ahead of the average for the region!

These are the grid cells in KwaZulu-Natal with records uploaded in 2021 so far. Impressive! On 1 February 2021, for KwaZulu-Natal as a whole, the median of the medians was 23 March 2015. Half the records in half of the 169 grid cells with records are older than this. This means that the average age of the OdonataMAP data for KwaZulu-Natal is 5 years 1 month. This is only nine months behind the average for the region!

Only a handful of grid cells in the Eastern Cape have OdonataMAP records uploaded in 2021 so far. Impressive! On 1 February 2021, for Eastern Cape as a whole, the median of the medians was 5 November 2015. Half the records in half of the 181 grid cells with records are older than this. This means that the average age of the OdonataMAP data for Eastern Cape is 5 years and 3 months. This is only one month behind the average for the region! Well done to the Eastern Cape, and please keep the records pouring in.

These are the grid cells in the Western Cape with records uploaded in 2021 so far. Impressive! On 1 February 2021, for the Western Cape as a whole, the median of the medians was 25 March 2017. Half the records in half of the 170 grid cells with records are older than this. This means that the average age of the OdonataMAP data for the Western Cape is 3 years and 10 months. This is 15 months ahead the average for the region! Great achievement to the OdonataMAPpers of the Western Cape.

This is a New Year’s Day record of a very common species uploaded to OdonataMAP by Corrie du Toit. This Nomad had wandered close to the southern tip of Africa, not far from Cape Agulhas. The record is curated at http://vmus.adu.org.za/?vm=OdonataMAP-102577. Corrie is responsible for the row of three grid cells with 2021 records just west of Cape Agulhas

These are the grid cells in the Northern Cape with OdonataMAP records uploaded in 2021 so far. On 1 February 2021, for the Northern Cape as a whole, the median of the medians was 6 October 2017. Half the records in half of the 201 grid cells with records are older than this. This means that the average age of the OdonataMAP data for the Northern Cape is 3 years and 4 months. This is 22 months ahead of the average for the region! Of all the provinces, the Northern Cape has the most up-to-date database.

These are the handful of grid cells in the Free State with OdonataMAP records already uploaded in 2021 so far. On 1 February 2021, for the Free State as a whole, the median of the medians was 2 January 2015. Half the records in half of the 125 grid cells with records are older than this. This means that the average age of the OdonataMAP data for the Free State is 6 years and 1 month. This is 12 months behind the average for the region.

These are the grid cells in North West with OdonataMAP records already uploaded in 2021 so far. They are all along the southeastern border of the province! On 1 February 2021, for North West as a whole, the median of the medians was 6 December 2016. Half the records in half of the 78 grid cells with records are older than this. This means that the average age of the OdonataMAP data for North West is 4 years and 2 months. This is 12 months ahead of the average for the region.

So on 1 February 2021, the ordering of the provinces in terms of “up-to-dateness” is (1) Northern Cape (3.3 years), (2) Western Cape (3.9 years), (3) North West (4.2 years), (4) Gauteng (5.0 years), (5) Eastern Cape (5.2 years), (6) KwaZulu-Natal (5.9 years), (7) Free State (6.1 years), (8) Mpumalanga (6.4 years) and (9) Limpopo (6.9 years). The overall average against which these are compared is 5.1 years.

Of course, this is not the only ranking criterion. Aspects like percentage coverage, total numbers of records, and records per species-grid cell are also important. But for now the focus is on up-to-dateness. The hack to improve the up-to-dateness of a province is to “refresh” as many common species as possible in as many grid cells as possible. And this activity is precisely what helps to keep the distribution maps up to date.

So please adopt the mantra of “starting from scratch”. Please do upload everything, including the most common species, wherever you go, and especially in the grid cells with lots of data. These are the ones where it is easy to let up-to-dateness slip.

Acknowledgements

Rene Navarro developed the software used for these brand new measures up-to-dateness. Karis Daniel generated the maps. There would not be anything to write about without the contributions of the OdonataMAPpers. This is teamwork.

Thanks to Andries and Joey de Vries, Jaco Botes and Corrie du Toit for being out in the field on New Year’s Day and taking the photographs used to illustrate this blog.

Progress with BirdPix in the Free State during 2020

We will slowly work out way through projects and provinces! We have done BirdPix in the Western Cape.

This map shows the number of bird species recorded for BirdPix in each quarter degree grid cell of the Free State at the end of 2020.

BirdPix in the Free State, 2020. The number in each grid cell is the total number of bird species recorded in the grid cell up to 28 December 2020

And this what this same map looked like a year ago, on 31 December 2019.

BirdPix in the Free State, 2019. The number in each grid cell is the total number of bird species recorded in the grid cell up to 31 December 2019

You have to work a little bit to see the advances. The number of bird species for Bloemfontein grid cell (2926AA near the centre of the map) increased by 18 from 183 to 201, and there have been lots of other increases. Seven grid cells got their first BirdPix records during 2020. The maps below provides a measure of BirdPix activity in the Free State during 2020.

BirdPix in the Free State in 2020. The number in each grid cell is the total number of bird species recorded in the grid cell, considering only records uploaded to BirdPix between January and December 2020

So although the number of species in the Bloemfontein grid cell increased by 18, records were submitted for 106 species. That is precisely what we are looking for. The remaining 88 species were “refreshed“, in the sense that they now have records from 2020, confirming that they still occur in the grid cell.

It is this blue map which highlights the main focus of the Virtual Museum nowadays. The emphasis has shifted from “species per grid cell, irrespective of when the records were made”, to keeping the database “refreshed” and up-to-date.

Measuring “up-to-dateness” …

Here is another (and fairly subtle) approach to measuring “up-to-dateness” in the Free State overall! For each grid cell, we find the date of the last record for each species. If species are “refreshed” regularly, this date will be recent. We next sort all the “last recorded” dates for all the species in a grid cell from oldest to most recent. Calculate the date in the middle. Half the species were last seen before this date, and half have been seen subsequently. We  want to keep this middle date as recent as possible. (Statisticians call this “middle date” the median, and there is a blog about this concept.)

Next, we take all the grid cells in a region (e.g. a province like the Free State) and we compute the middle dates (the medians) for all of them. We hope, on average, that these middle dates are pretty recent. To measure how recent they are overall, we calculate the middle date of all the middle dates in the region. We are happiest if this date is recent. We prefer this date to be recent, because if this median of medians is not too far in the past, it means that, overall, the species lists for the grid cells in the region are pretty up-to-date.

At the end of 2020, for BirdPix in the Free State, the median of the medians was 8 August 2016. In other words, half the grid cells had their own medians before this date, and half of them had medians after this date. August 2018 is four years and five months ago, or 53 months. So we can make the statement: at the end of 2020, BirdPix was, on average, 53 months behind the clock. We can repeat this arithmetic, pretending we are have turned the clock back to December 2019, a year ago. The median of the medians then would have been 9 September 2015, 52 months prior to December 2019. So, in terms of up-to-dateness, BirdPix in the Free State slipped by one month during 2020. Considering the difficulties of 2020, this is a satisfactory outcome.

As citizen scientists, we should aim to improve the up-to-dateness during 2021. We can achieve this by adopting the New Year’s resolution for Team Virtual Museum. “Starting in my home grid cell on 1 January 2021, I will upload records to the Virtual Museum of as many species as possible (and I will be especially careful not to neglect the common species). Wherever I travel in 2021, I will do my best to keep the distribution maps up-to-date for as many species as possible.” We should aim to do this wherever we are, and for all the projects of the Virtual Museum.

… more summary numbers …

At the end of 2020, there were 6,523 records in BirdPix which had been identified to species level. These included 425 bird species. The records were for 163 quarter degree grid cells. There are 153 grid cells which are entirely within the Free State, and another 85 which have overlaps between the Free State and other provinces or with Lesotho. That is a total of 238. So there are records for 163 of the 238 quarter degree grid cells in Lesotho. In the top map, the number of species recorded to date in each grid cell at the end of 2020 is given. If you add these numbers up, the total is 3,189 “species-grid cells”.

At the end of 2019, these figures were 5,524 records, for 418 species. So we added 999 records, and seven species in the year. During 2020, the number of grid cells with records increased by seven, from 156 to 163. The number of “species-grid cells” increased from 2,871 to 3,189, an increase 318. In other words, 318 species were recorded in grid cells from which they had not been recorded at the start of 2020.

Refreshment dip into Yzerfontein during lockdown

Kitch garden bird

At the beginning of May 2019, the quarter degree grid cell for Yzerfontein had 15 BirdPix records for 12 species. An expedition on 5 May 2019 changed that to 67 records of 39 species. There is a blog about this! During the remainder of 2019 and during the pandemic-dominated 2020, citizen scientists slowly improved these figures to 96 records of 45 species. At the start of 2021, South Africa was back in lockdown, a 6 am curfew meant that early morning starts were not feasible, and the beaches were closed. So on 9 January, it was time for a dip back into Yzerfontein to try to refresh as many species as feasible. It was time to honour the New Year’s resolution for Team Virtual Museum for citizen scientists …

… “Starting in my home grid cell on 1 January 2021, I will upload records to the Virtual Museum of as many species as possible (and I will be especially careful not to neglect the common species). Wherever I travel in 2021, I will do my best to keep the distribution maps up-to-date for as many species as possible” …

The edge of quarter degree grid cell 3318AC Yzerfontein is an hour from home. So with a 6 am start, I was at the intersection of the R27 and the R315 to this summer holiday resort by 7 am. See the map below …

Yzerfontein QDGC 3318AC

Underneath this map on the Virtual Museum website is the list of 45 species recorded so far. When I started, the bottom part of this list looked like this:

The end of the species list for the Yzerfontein QDGC before 9 January 2021

Here are species 34 to 45 on the list. The column that has 96 at the bottom tells us the number of BirdPix records for each species (and if you click on “Records” over on the right you get to see their details). The second last column gives the date of the most recent record for each species. So there are four records of Cape Sparrows, the most recent of which is on 12 December 2019.

Understanding the dates at the bottom of the column provides real insight into the up-to-dateness of the data for this grid cell. It is unusual for both the dates to be the same! This is how to calculate the top date of the two. Take the 45 “most recent” dates, and sort them. Pick the date in the middle: 5 May 2019. Half of the 45 species have been seen since this date and half before this date. For the bottom date, do the same process but with all 96 records. Half the records were made before 5 May 2019, and half of them since. This way of calculating the “date in the middle” produces a value called the “median” by statisticians. There is a blog about this!

After I got home, I submitted 50 records to BirdPix. Overnight, the members of the BirdPix expert panel have confirmed the IDs of all them. They are an awesome and dedicated group of people, and this is an important opportunity for us to express our thanks to them. The number of records for the grid cell has increased by 50 from 96 to 146. The number of species has grown by eight from from 45 to 53. Here is the list from House Sparrow to the end:

The end of the species list for the Yzerfontein QDGC after 9 January 2021

House Sparrow has shifted from being number 34 in the previous list to 39 now. In this part of the list, the new species are Southern Masked Weaver (47), African Sacred Ibis (51) and African Hoopoe (52). But the important thing to look at is how the median dates have changed. The median of the “last recorded dates” is now yesterday, 9 January 2021. That is because, when you sort these 53 dates, more than half the species were recorded on 9 January 2021! The bottom date has advanced from 5 May 2019 to 11 December 2019. Half of the 146 records were made before 11 December 2019, and half of them since. And that is of no concern!

The important thing is not the eight new species, but the fact that the median of the “last recorded dates” is right up-to-date. More than half the species were “refreshed“. The big challenge for 2021 is going to be to get this date into 2021 for as many grid cells as possible for as many projects as possible. Yzerfontein was easy; it only had 45 species.

Here are a few of the records from 9 January 2021:

African Hoopoe
In the Virtual Museum, this hoopoe is curated at http://vmus.adu.org.za/?vm=BirdPix-151655. This is the first record of the species in the grid cell for BirdPix

The hoopoe was on a lawn, in the dark shade under a tree. Considerately, it flew up onto a balcony and posed there. A chick is destined to receive a juicy worm.

Birds in flight are a challenge …

Black-shouldered Kite in flight
This Black-shouldered Kite can be found in the Virtual Museum at http://vmus.adu.org.za/?vm=BirdPix-151653

… but this Black-shouldered Kite hovered obligingly.

You will be pleased to know that this photo did not find its way into the Virtual Museum …

Kitch garden ornament

… the gull and the spurfowl seem oblivious to the kitsch garden ornament.

Law enforcement was prominently parked in the beach parking area, and no one was defying the lockdown regulations. There were lots of gulls on the beach, but the White-fronted Plovers had clearly not discovered that the beaches were deserted of humans, and they had congregated on the salt pan near the Strandkombuis.

White-fronted Plover on saltpan at Yzerfontein
Now you can see why it is called a White-fronted Plover! It was far away, and it was a dull morning. Look at the other photos curated at http://vmus.adu.org.za/?vm=BirdPix-151665!

You can find the complete BirdPix list of species for the Yzerfontein grid cell (and the map) by going to the link http://vmus.adu.org.za/vm_locus_map.php?vm=birdpix&locus=3318AC. (You can find the lists for other projects by changing “vm=birdpix” to other projects, eg “vm=reptilemap”, and you can change the code for the quarter degree grid cell).

So Yzerfontein is nicely refreshed for the birds. The dragonflies do however need attention (see http://vmus.adu.org.za/vm_locus_map.php?vm=odonatamap&locus=3318AC; the median date s in 2011!); there MUST be some freshwater somewhere in the grid cell. For LepiMAP, the median last record date is 1 February 2015 (see http://vmus.adu.org.za/vm_locus_map.php?vm=lepimap&locus=3318AC). But for ReptileMAP it is way back in 25 August 1983. Gosh, that is nearly four decades ago. Once the data starts to be this old on average, it ceases to be really valuable as current evidence of species distributions. That is the ultimate challenge.

This leads us back to our Virtual Museum resolution for 2021: “Keep the distribution maps up-to-date”. It is the commonest species in well-covered grid cells that are easy to neglect. And, at the same time, they are the easiest to keep up-to-date.

There are positives to having to leave after sunrise. Under normal circumstances, it would not have been light when I passed the huge Vissershok Landfill Site. A decade or so ago, this dump was well-known for hosting a some quite exotic storks: Marabou and Open-billed, and here is an amazing record from 2009 of White Storks at the dump. Yesterday, when it was still too early for a self-respecting, and presumably well-fed, White Stork to be up and about, the lamp posts at the nearby weighbridge where heavy trucks get examined were each occupied:

Grubby White Stork at Vissershok dump
Curated at http://vmus.adu.org.za/?vm=BirdPix-151593. This is only the third record of White Stork in the Bellville quarter degree grid cell 3318DC; to see the full list of bird species in BirdPix for this grid cell, go to http://vmus.adu.org.za/vm_locus_map.php?vm=birdpix&locus=3318DC

The moral of this story is that birds with white feathers should not feed in rubbish dumps.

But the moral of the blog is simple. Our anthem for 2021 is “refresh, refresh, refresh!”

BDInsight – Festive Season 2020/21

A very Happy New Year to each and everyone of you. It is hard to believe that 2020 is behind us and 2021 has started. The world is still in the grips of Covid-19, but we have become accustomed to this “new” way of living. With these challenges great opportunities also arise and innovation happens. It has been a year of growth and the opening of new doors.

The BDI Citizen Science community has grown stronger. Biodiversity mapping has been a great way to keep sane throughout 2020. We held several Citizen Scientist Hours which opened up a whole new world to all of us. To catch up on the various awesome talks, visit our YouTube Channel.

Virtual Museum

New Year’s resolution for Team Virtual Museum: “Starting in my home grid cell on 1 January 2021, I will upload to the Virtual Museum records of as many species as possible (and I will be especially careful not to neglect the common species). Wherever I travel in 2021, I will do my best to keep the distribution maps up-to-date for as many species as possible.”

In spite of all the challenges, 2020 was BestYearEver for the Virtual Museum, by a margin of 24%. That is an awesome achievement, Team Virtual Museum. 2020 is now history. Even the colour of its line on this plot has changed from red to blue. The current year is always RED, and in the bottom left hand corner you can see that the first records for the year have already been submitted.2021 needs to be the year of “refreshment” of old records. Let’s pretend that we are starting again from scratch. This is the strategy for keeping the distribution maps up-to-date. This is the primary need of biodiversity conservation planning and priority setting. Without up-to-date maps (and historical maps to show how distributions are changing), conservation planning for species is as effective as winking in the dark! Strength and peace to all citizen scientists in 2021.

Fundamentals of Citizen Science – BDI Course

Rick Nuttall revealed the new BDI course, to be called Fundamentals of Citizen Science in one of our recent BDI Citizen Scientist Hour events. We plan to repeat the course at least three times in 2021. The planned dates and places are:

  • 21-28 February at the Karoo Gariep Nature Reserve (New Holme Guest Farm), Hanover, Northern Cape
  • 11-18 April at Louisvale Farm, north of Carnarvon, Northern Cape
  • 6-13 August at Botuin, Vanrhynsdorp, Western Cape.
  • The provisional cost is R11,900 per person for the course including food and accommodation. Please send emails expressing interest to megan@thebdi.org

You can read more about what the courses involver here.

OdonataMAP

There are now more than one hundred thousand (100,000) photographic records in OdonataMAP. That is a huge. For the purpose of producing distribution maps for the dragonflies and damselflies of Africa, the OdonataMAP data is supported by the 121,000 records of ADDO data, mostly the historical data in museum collections. Within the next year, we should aim to get the OdonataMAP database larger than 121,000. 100,000 photographic records. That is a stunning achievement! Thank you, OdonataMAPpers, and well done!

Progress with BirdPix in the Western Cape during 2020

Southern Double-collared Sunbird

This is planned to be the first of many similar blogs. We are starting with an easy project, BirdPix, in my home province, Western Cape. It is still a bit experimental!

This map shows the number of bird species recorded for BirdPix in each quarter degree grid cell of the Western Cape on 28 December this year, very close to the end of 2020.

BirdPix in the Western Cape, 2020. The number in each grid cell is the total number of bird species recorded in the grid cell up to 28 December 2020

And this what this same map looked like a year ago, on 31 December 2019.

BirdPix in the Western Cape, 2019. The number in each grid cell is the total number of bird species recorded in the grid cell up to 28 December 2019

These two maps show impressive progress during 2020 for the total number of species in many grid cells.  And you have to work quite hard to find the grid cells where the year-end totals are the same!

But the emphasis in the Virtual Museum has shifted from “species per grid cell, irrespective of when the records were made”, to keeping the database “refreshed”. The map below provides a quick measure of freshness. It shows the number of species per grid cell, for records uploaded in the year 2020.

BirdPix in the Western Cape in 2020 only. The number in each grid cell is the total number of bird species recorded in the grid cell, considering records uploaded to BirdPix between 1 January 2020 up to 28 December 2020 only

The logic here is that the more species uploaded for a grid cell in 2020, the more up-to-date the species list for that grid cell must be. We don’t know yet what this map will look like for other projects and for other provinces. But this has to be impressive! Some grid cells, those in darker shades of blue, had lots of species in 2020. Those with beige shades had only a few. But an awful lot of grid cells in the Western Cape were visited during the year.

The Cape Town grid cell had 169 species at the end of 2019 (second map). This had grown by 20 species to 189 at the end of 2020 (first map). But the total number of species submitted during 2020 was 135 (third map). This means that 20 of the 135 species were new to the grid cell, and that the remaining 115 species were used to do a 2020 refreshment of species last recorded in earlier years! This concept of “refreshing” old records is one that we are going to talk about more and more. There is a blog about this.

And here is a fairly subtle approach to measuring “up-to-dateness” in the Western Cape overall! For each grid cell, we find the date of the last record for each species. If species are “refreshed” regularly, this date will be recent. We next sort all the “last recorded” dates for all the species in a grid cell from oldest to most recent. Calculate the date in the middle. Half the species were last seen before this date, and half have been seen subsequently. We  want to keep this middle date as recent as possible. (Statisticians call this “middle date” the median, and there is a blog about this concept.)

Next, we take all the grid cells in a region (e.g. a province like the Western Cape) and we compute the middle dates (the medians) for all of them. We hope, on average, that these middle dates are pretty recent. To measure how recent they are overall, we calculate the middle date of all the middle dates in the region. We are happiest if this date is recent. We prefer this date to be recent, because if this median of medians is not too far in the past, it means that, overall, the species lists for the grid cells in the region are pretty up-to-date.

At the end of 2020, for BirdPix in the Western Cape, the median of the medians is 24 October 2018. In other words,  half the grid cells have their own medians before this date, and half of them have medians after this date. October 2018 is 26 months ago. So we can make the statement: BirdPix is, on average, 26 months behind the clock. Before we decide whether this is good or bad, we will need to do these calculations for lots of other projects and provinces. It will probably turn out to be awesomely excellent.

We can repeat this arithmetic, pretending we are have turned the clock back to December 2019, a year ago. The median of the medians was 14 December 2015. Gosh, this is 48 months previous to December 2019. In other words, at the end of 2019, BirdPix was 48 months behind the clock in the Western Cape. What this means is that, during 2020, BirdPix in the Western Cape “improved” from being 48 months behind the clock to being 26 months behind the clock. That is a 22-month improvement. That sounds pretty impressive.

New Year’s resolution for Team Virtual Museum

“Starting in my home grid cell on 1 January 2021, I will upload records to the Virtual Museum of as many species as possible (and I will be especially careful not to neglect the common species). Wherever I travel in 2021, I will do my best to keep the distribution maps up-to-date for as many species as possible.”

Southern Double-collared Sunbird
This photo illustrates the point that photos for the Virtual Museum do not have to be works of art. So long as the species in the photo is identifiable, it qualifies! But this Southern Double-collared Sunbird is pushing the patience of the expert panel to the limits. Here it is in BirdPix: http://vmus.adu.org.za/?vm=BirdPix-150313. It was the first record of this species in quarter degree grid cell 3418AD, at Cape Point, so it was a bit of a priority

Postscript: Finding the ruddy quarter degree grid cells

The frustrating thing about all these maps is this problem: “How do I find a particular grid cell on the ground?” Doing this is harder than it needs to be, because the clown who designed the system of codes for quarter degree grid cells ought to have been allowed to design only one more thing: his tombstone! It is a messy and unnecessarily complicated system. But we are stuck with it, so we have no choice but to get to grips with it. If you pick a grid cell in one of these maps, and want to work out its six character code, here is the recipe.

(1) Find the four digits for the one degree grid cell. To do this, first go up to the next thick line above your grid cell, and follow this line to the degrees number on the left edge of the map. In South Africa, there are always two digits. 33 is an example. They are the first two digits you need. Then go left from your chosen grid cell to the next thick line. The degrees number is on the bottom edge of the map. Also, two digits; numbers like 21. Run the four digits together. For the example above, the one degree grid cell is known as 3321.

(2) There are 16 quarter degree grid cells in the one degree grid cell. They are arranged in four rows and four columns, and each quarter degree grid cell has a code consisting of two letters (see the pattern below). Which row and which column is your grid cell in? Suppose it is in the third row and the second column. Use this pattern guide to find the two letter code for the grid cell in this position. Third row, second column is position CB. Add these letters onto the four digits for the one degree grid cell. So the code for the grid cell you are looking for is 3321CB. Gosh, that is not easy.

To find a list of the bird species that have been submitted to BirdPix for grid cell 3321CB, go to http://vmus.adu.org.za/vm_locus_map.php?vm=birdpix&locus=3321CB. You will discover that it needs a visit!

You can put any grid cell you need as the locus (ie adjust locus=3321CB to whatever you need). You can also change projects; eg replace vm=birdpix by vm=reptilemap to get a list of reptiles for any quarter degree grid cell.