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NOT THIS TIME… how the could actually enter the nest backs out the way she came in or, if the nest to lay an as the seemed to be too is large enough, swivels around and emerg- am fascinated by , and in par- large. Does it go into the nest to lay, or does es head-first, in both cases holding the host ticular how the hosts are fooled into it lay elsewhere and then carry the egg in its egg she has replaced. rearing a chick, which to us is obvi- beak to the nest and exchange it for one of As Malcolm’s wonderful image shows, Iously completely different. Here in the the weaver’s ? weavers attack Diederik Cuckoos vi- UK we have only one cuckoo species, the Malcolm Bond, United Kingdom ciously, and it has been suggested that the , which I have never long entrance tubes of many weaver nests seen and have heard on only a few occa- Researcher Dr Claire Spottiswoode com- function as a deterrent to cuckoos as well sions. I have, however, seen films on TV ments: As Malcolm correctly notes, Com- as predators. At worst, cuckoos can get showing how this cuckoo removes an egg mon Cuckoos in Europe and Asia lay their stuck (one was even found dead halfway from a warbler’s nest and then lays its own eggs directly into host nests – although it up a weaver tube) and, at best, perhaps the egg in place of it, but that is an open cup was argued for centuries that they rather tube slows them down, giving the weavers nest, so the bird simply perches above it to carry their egg in their bill, or swallow it a better chance of spotting the intruder deposit an egg. and regurgitate it into a host nest. It took and alerting them to carefully inspect their We visit South Africa regularly, going the obsessive observations of Edgar Chance clutch for a possible impostor – and reject mainly to the Kruger National Park, and (an egg collector who spent years in single- it if they find one. I have been surprised by the large number minded pursuit of the sight of a laying of brood-parasite species in this country. cuckoo) in the 1920s to prove that they lay GANG WARFARE Several years ago there was a large colony their egg on the spot, and with remark- of Lesser Masked Weavers in Satara Rest able speed. Even when parasitising hole- or he cover of the May/June 2014 issue Camp in Kruger. As I have always won- domed-nesting species, such as Redstarts and the article ‘Touch & Go’ by Chris dered how a Diederik Cuckoo manages to or Wrens, Common Cuckoos simply hold van Rooyen in which he described get its egg into a weaver’s nest, I staked out their vents against the entrance hole and Tan incident of Pale Chanting Goshawks at- the weaver colony with my camera. I could project the egg into the nest within. tacking an owl, brought to mind an incident see the cuckoos flying around and after To date there is still no evidence that any I witnessed in the Kgalagadi Transfrontier about an hour I managed to get a single other cuckoo species, including Diederik Park a few years ago. decent picture of one attempting to enter Cuckoo, does otherwise. Anna Lindholm’s At about 14h00 on 23 June 2011, when a weaver’s nest. research on Diederik Cuckoos in KwaZulu- my wife and I reached Kaspersdraai, some The cuckoo was immediately set upon by Natal revealed that within the weaver nest 30 kilometres south of Nossob Camp, our two male weavers and after a few moments chamber, a female cuckoo holds a host egg attention was drawn to the presence of 10 or it fell away from the nest. Unfortunately I in her bill while laying her own, all in the more Pale Chanting Goshawks perched on didn’t see any egg transfer, but I couldn’t see space of five to 10 seconds. She then either trees around the waterhole; I have never >

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seen such a concentration of goshawks be- fore or since. One bird was on the ground 2 near the waterhole but flew up and landed in the mud, and began pecking at some- thing. It then moved forward into the shal- landmarks such as a road, a drainage line or low water where it just stood motionless for a ridge. Territorial defence duties are per- a while. And then the action began. formed exclusively by the males: females One by one, three or four of the gos- only defend the nest contents against other hawks that were perched nearby took off females. and began circling the waterhole. They From the three images supplied it seems proceeded to attack the goshawk standing as though the two families assembled at a in the water, each of the aggressors peel- waterhole that demarcated the boundary be- ing off from the circle and diving down, tween their territories. A breeder that gives one after the other. Initially they merely the wheeee alarm call will usually convene ‘buzzed’ the bird in the water, sweeping such an assembly. In this instance, one of just over its head and causing it to duck, 3 the males, perhaps an inexperienced non- but then the attacks became more concert- breeder, ventured into the waterhole that the ed and on several occasions the bird was gradually dispersed in different directions, other family regarded as its property. The knocked into the water (1). leaving behind the injured bird. males from the latter family then attacked After a while there was a cessation of hos- What led to so many Pale Chanting Gos- and, as Mr Leach pointed out, the aggressors tilities, with the bird in the water being left hawks to congregate and then attack one of initially buzzed the intruder. When the in- looking bedraggled and totally confused. It their kind is beyond me. It would be inter- truder did not abscond, the bird was physi- took the opportunity to get out of the water, esting to know if this is common behaviour cally thumped. As described, the attackers although it was clearly injured and struggled and what is likely to have given rise to the will typically fly in a ferris-wheel formation to do so. When it reached the mud along- incident. and each individual will attack the trans- side the water, it held its left wing at a pecu- L.E. Leach, Port Alfred, Eastern Cape gressor on the down flight. Pale Chanting liar angle, presumably due to an injury. Goshawks can also kick surprisingly hard, But that was not the end of its difficulties Researcher Professor Gerard Malan com- so the intruder was taking some serious hits. as it was once again attacked and knocked ments: Pale Chanting Goshawks are social It is not clear from the images how severe down a couple of times (2). When it at- , and live in loose family groups. Mr the injury was, but the bird’s life was at stake. tempted to fly off it could not do so and Leach does not say if the chanting goshawks We often see raptors sitting lazily on a fell over. Eventually it scuttled off holding perching around the waterhole were adults perch or, at best, attentively watching some- its left wing, which was apparently broken, or juveniles but, in high-quality habitats, thing. It is only when one looks at these jutting up into the air (3). It took refuge un- families consist of juveniles, non-breeders, photographs and those of the Pale Chanting der some nearby bushes, while its attackers and a breeding pair occasionally assisted by Goshawks attacking a Verreaux’s Eagle-Owl circled once or twice and then perched on a second breeding male. (in the previous issue) that we realise how the tree tops, among the six or seven other Pale Chanting Goshawks are also fiercely raptors live at the coal-face of survival, and goshawks that had watched the events. territorial and actively defend their bound­ that they can easily lose their lives in intra- After a few minutes all the goshawks aries, which are usually easily identifiable and inter-specific skirmishes. 

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