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International Citizen Science Day in The Company’s Garden

Posted on 14/04/2018 by Les Underhill

International Citizen Science Day in The Company’s Garden – by Les Underhill

All but one of the thousands of people in The Company’s Garden, in the heart of Cape Town, were there to enjoy the autumn sun, and hoping for rain. I was there to celebrate International Citizen Science Day, Saturday, 14 April 2018. The sun made it easy to take photos for the Virtual Museum (http://vmus.adu.org.za).

The dragonflies and damselflies, taken together, are called the Odonata. The damselflies mostly fold their wings over their backs, but they are mainly associated with really clean freshwater. So it was a bit of a surprise to find a damselfly sitting on the stalks emerging from the ornamental pond in the top photo.

The pair of Egyptian Geese in this pond had one gosling. Probably this was the only one left of a brood; the average starting off size of a brood is eight. This brood shrinkage is not a conservation issue in The Company’s Gardens. There is no shortage of Egyptian Geese.

This goose parent used the fountain in the ornamental pond as lookout. Cecil John Rhodes, of Cape to Cairo ambitions, has turned his back on this Egyptian Goose. Reminders of the failure to put a railway from here to Egypt is apparently a stressful topic.

The war horses and soldiers of the Delville Wood Memorial have to withstand the unsavoury attentions of the Hartlaub’s Gulls. They provide a great vantage point from which they can swoop down on anyone who scatters any food.

The Company’s Garden has a well-maintained section of vegetables. This is the best spot for butterflies. The most abundant butterfly today was the Cabbage White. This is South Africa’s only invasive alien butterfly. It was first recorded in Sea Point, Cape Town, in 1996, and has already expanded its range as far as the Eastern Cape.

This African Monarch was still flying in spite of large fractions of its wing area having worn away.

Here is a younger and more vibrantly coloured African Monarch.

Outside of suburbia, the Garden Acraea, occurs mainly in forest and woodland. It has moved into the suburbs on a large scale, because its favourite host plant on which its caterpillars feed is the Wild Peach Kiggelaria Africana, and these are grown in many gardens.

Another species that originally was a forest inhabitant is the Hadeda. This noisy bird has made itself at home in the suburbs, and in The Company’s Garden it happily feeds in the beds while people walk by on the adjacent footpaths.

This Grey Squirrel is another introduced alien, which seems to have The Company’s Garden as the epicentre of its Cape Town distribution. Here is one, of hundreds, and it is feeding on an acorn, from an introduced oak tree. So far, there is nothing unusual about all of this.

But the squirrel moves off looking like a rabbit. Somehow, it is coping with life minus its bushy tail.

All these photographs will be uploaded to the Virtual Museum. They will be valuable in two ways. They will confirm the continued existence of each species in this locality. And especially for the butterflies, and for the damselfly, these records will provide information on the time of the year when they are in flight. As we move through April, and the weather in Cape Town gets cooler, we anticipate seeing fewer and fewer of these two groups of insects.

Paardeberg/Site report

Paardeberg site report – 2018/04/07

Posted on 11/04/2018 by Les Underhill

By Les Underhill. Photo credits: Les Underhill and Dieter Oschadleus

Team BDI explored the northwest corner of the Paardeberg on Saturday 7 April 2018. We visited the part of this mountain range which is closest to Malmesbury. Technically, the Paardeberg is a series of granite plutons – dome-shaped hills. It was called the Paardeberg because, when discovered, it had been inhabited by quaggas, which to the early settlers were horselike. This is a fascinating area, and one we plan to revisit.

We joined an expedition led by Arnold van der Westhuizen to check two camera traps. Leopard scats had been reported here recently, and the cameras had been set up in the hope of confirming the presence of this seldom-seen animal. We found leopard scats and uploaded them to MammalMAP: http://vmus.adu.org.za/?vm=MammalMAP-24172

On the foothills of the Paardeberg, the main crop is grapes, but there was no water in the farm dams for irrigation this summer, and there was no harvest in the higher lying vineyards. Above the agricultural areas is a band of renosterveld. Go a little higher, and the proportion of plants which are proteas, ericas and restios increases, and renosterveld gives way to fynbos.

The camera traps had taken a total of 44 photos. All of them turned out to be baboons, and some were caught in some unusual poses! Maybe a leopard or two would help create a “landscape of fear” for the baboons.

At the end of long, dry, drought summer, biodiversity was scarce. This was one of only two butterflies we saw. It is a Cape Black-eye Leptomyrina lara (http://vmus.adu.org.za/?vm=LepiMAP-645342) This is a species that frequently rests on bare ground, and did so for us. The Cape Black-eye occurs mainly in the more arid western half of South Africa, in Lesotho and it also occurs northwards into Namibia. This is the sixth record of the species in the Paardeberg, and the others have also been within a few kilometres of this spot.

The Crimson Speckled Footman Utetheisa pulchella is a moth that flies in the daytime (http://vmus.adu.org.za/?vm=LepiMAP-645342). It looks like a white butterfly in flight; but when it is settled the red and black pattern on the white wings makes it instantly recognisable. These moths are unpalatable to birds; the bold wing colours serve as warning to predators: “I am toxic”, or, in technical terms, “I have a condition called aposematism.” The Crimson Speckled Footman has a wide distribution across Africa and southern Asia. The South African distribution map should show an almost continuous range.

We didn’t see any mammals, not even a baboon, but we did find this porcupine quill and submitted it to the MammalMAP section of the Virtual Museum (http://vmus.adu.org.za/?vm=MammalMAP-24182).

Two species scorpions were found. This one is Uroplectes carinatus (http://vmus.adu.org.za/?vm=ScorpionMAP-3161). The scorpions don’t yet have English “common” names, like the birds, butterflies and dragonflies do. The identity of the second species is still being debated by the specialists (http://vmus.adu.org.za/?vm=ScorpionMAP-3160).

We are grateful to Arnold van der Westhuizen for being our guide.

Site report

Lacewings at Little England, Beaufort West

Posted on 02/04/2018 by Les Underhill

Nesoleon boschimanus. Photo credit: Les Underhill (2018)

Report by Les Underhill

Lacewings are not one of the charismatic groups of insects, and have been poorly studied. They consume aphids and do pollination, so they are one of the key ecosystem service providers, and deserve better attention than what they have received to date. There is only one entomologist in South Africa who has focused on lacewings, Dr Mervyn Mansell, at the University of Pretoria. He says that, in South Africa, there are currently 415 described species in 14 families of lacewings. There are many taxa that await description, and he reckons that we should eventually end up with about 500–550 species for South Africa. For the whole of Africa, it is likely that there will prove to be 1000–1500 species.

On three trips to the Landmark Foundation’s farm at Little England in the Karoo north of Beaufort West a total of 18 lacewing have been photographed and uploaded to the LacewingMAP section of the Virtual Museum (http://vmus.adu.org.za). 13 have been identified to species level, three to genus and, for one, the photo was only good enough for the ID to be done to family. The number of species so far is a paltry six! But it is a start. These are the first ever records for this grid cell.

Mervyn Mansell, who does the identifications for LacewingMAP, reckons that we could expect at least 50 species in that area. “It is actually an extremely rich area for lacewings. Lots of fieldwork needs to be done here.”

The first six species for this grid cell are listed below. The species notes were written by Mervyn Mansell in his comments on the identification. The number of records to date is given, as well as the link to the record in LacewingMAP with what is currently the best available photo of the species in the grid cell. The distribution map for each species, based on the LacewingMAP database, is also provided. The take home message from these maps is plain: Our knowledge of the distributions of the lacewings is weak.

Systematic list of lacewings recorded on the farm Little England

Centroclisis maligna. Photo credit: Les Underhill (2018)

Centroclisis maligna (Myrmeleontidae)

This species is fairly common and widespread in the drier western parts of southern Africa. It is readily distinguished form other Centroclisis species by its reddish colour. The large robust three-toothed larvae live freely in sand and do not construct pitfall traps.

One record: http://vmus.adu.org.za/?vm=LacewingMAP-10704

–000–

Creoleon mortifer. Photo credit: Les Underhill (2018)

Creoleon mortifer (Myrmeleontidae)

A common and widespread species, occurring throughout most of southern Africa and northward. It is highly variable, often with black streaks in the wings that have led to numerous synonyms. Rests with wings wrapped around the body. Larvae live freely in sand.

Two records: http://vmus.adu.org.za/?vm=LacewingMAP-10758

–000–

Myrmeleon doralice. Photo credit: Les Underhill (2018)

Myrmeleon doralice (Myrmeleontidae)

This species is common and widespread throughout southern Africa, particularly in the drier areas. Larvae construct pits and are pinkish in colour. Although the adults are fairly common, the larvae are not frequently encountered, although they are pit builders, and usually occur in open exposed situations.

Three records: http://vmus.adu.org.za/?vm=LacewingMAP-10706 m

–000–

Nannoleon michaelseni. Photo credit: Les Underhill (2018)

Nannoleon michaelseni (Myrmeleontidae)

This species is widespread in South Africa and Namibia, and is fairly common in the drier western parts of the subregion. It is currently the only species in the genus, although another undescribed species is also known. It is characterized by the broad clear wings and long clavate antennae. Nothing is known of its biology.

Two records: http://vmus.adu.org.za/?vm=LacewingMAP-10701

–000–

Nesoleon boschimanus (Myrmeleontidae)

Three records: http://vmus.adu.org.za/?vm=LacewingMAP-10705

–000–

Dichochrysa tacta. Photo credit: Les Underhill (2018)

Dichochrysa tacta (Chrysopidae)

Another of the “brown” “green lacewings”. Fairly widespread and common in the drier western parts of South Africa. Not known from neighbouring countries. Larvae live freely on vegetation, where they are active predators.

Two records: http://vmus.adu.org.za/?vm=LacewingMAP-10784

–000–

We are grateful to the Landmark Foundation for their warm hospitality at Little England. Mervyn Mansell’s role in doing the identifications and writing the comments is crucial to the success of this project.

The data were extracted from the LacewingMAP section of the Virtual Museum (Animal Demography Unit (2018). LacewingMAP Virtual Museum. Accessed at http://vmus.adu.org.za/?vm=LacewingMAP on 2018-04-02)

Archive/Bird ringing/Birds/Paardeberg

Bird ringing report – Paardeberg 28 March 2018

Posted on 31/03/2018 by Dieter Oschadleus

Cape Robin-chat *Cossypha caffra*. Photo credit: Dieter Oschadleus (2018)

Cape Robin-chat – Virtual Museum record

Report by Dieter Oschadleus on our first BDI bird ringing in the Paardeberg.

The Paardeberg stands out as a mountainous island in an agricultural landscape between Paarl/Wellington and Malmesbury in the Swartland region of the Western Cape. Very little bird ringing has taken place here, so Les Underhill and I had a bird ringing session in the Paardeberg, on Bowwood Farm, on Wednesday, 28 March 2018.

The top species was Cape White-eye (n=22), followed by Southern Masked Weavers (n=8), of which two were males in partial breeding plumage. The ring of one bird has been recovered in the Paardeberg area, a Cape Weaver ringed with ring 231054 in Tygerberg.

Thanks to Julian and Bridget Johnsen for hosting us! We hope to do a lot more bird ringing in the Paardeberg.