Short communications 29

Acknowledgements We should like to thank Prof. Derek Pomeroy for valuable comments on this manuscript, Roger Skeen for further information on ’s hobbies, and our guide Vicent Katwire for a safe journey through the street jungle of Kampala. Finally, we would be happy to receive further unpublished information of observations on the ecology of the two hobby species in . References Bijlsma, R. & van den Brink, B. 2005. A Barn Swallow Hirundo rustica roost under attack: timing and risks in the presence of African Hobbies Falco cuvieri. Ardea 93: 37–48. Brown, L.H., Urban, E.K. & Newman, K. 1982. The of Africa. Vol. 1. London: Academic Press. Carswell, M., Pomeroy, D., Renolds, J. & Tushabe, H. 2005. The atlas of Uganda. Oxford: British Ornithologists’ Club & British Ornithologists’ Union. Fenton, M.B., Rautenbach, I.L., Smith, S.E., Swanepoel, C.M., Grosell, J. & van Jaarsveld, J. 1994. Raptors and : threats and opportunities. Behaviour 48: 9–18. Ferguson-Lees, J. & Christie, D.A. 2001. Raptors of the world. London: Helm Identification Guides. Fuchs, J., Johnson, J.A. & Mindell, D.P. 2015. Rapid diversification of (Aves: ) due to expansion of open habitats in the Late Miocene. Molecular Phylogenetic and Evolution 82: 166–182. Haensel, J. & Sömmer, P. 2002. Taggreifvögel erbeuten Fledermäuse und Flughunde — Versuch einer Gesamtübersicht — und neueste Erkenntnisse zur Fledermausjagd der schnellsten Falken in Deutsch- land. Ornithologischer Jahresbericht Museum Heineanum 20: 99–141. Kityo, R. & Kerbis, J.C. 1996. Observations on the distribution and ecology of bats in Uganda. Journal of the East Africa Natural History 85: 49–63. Pitman, C.R.S. 1966. A further note on the breeding of the African Hobby Falco cuvieri Smith. Ostrich 37: 6–7. Probst, R., Nemeschkal, H.L., McGrady, M., Tucakov, M. & Szép, T. 2011. Aerial hunting techniques and predation success of Hobbies Falco subbuteo on Sand Martin Riparia riparia at breeding col- onies. Ardea 99: 9–16. Probst, R. 2013. Der Baumfalke in Kärnten. Eine inneralpine Studie zur Ökologie des Kleinfalken. Klag- enfurt: Naturwissenschaftlicher Verein für Kärnten. Stanton, D.J. 2016. Predation of dawn-swarming bats by Eurasian Hobby (Falco subbuteo). Journal of Raptor Research 50: 317–319. Steyn, P. 1965. A note on the breeding of the African Hobby Falco cuvieri Smith. Ostrich 36: 29–31. Remo Probst and Renate Wunder Neckheimstraße 18/3, A-9560 Feldkirchen, Austria; Email: [email protected]

Scopus 37(1): 27–29, January 2017 Received 24 February 2016

Observation of Grey Kestrel Falco ardosiaceus raiding the nest of Dickinson’s Kestrel F. dickinsoni in the Selous Game Reserve,

On 31 January 2014, along the shoreline of Lake Manze in the Selous Game Reserve, Tanzania, we heard loud and incessant screeching coming from the crown of a dead Borassus palm Borassus aethiopum where we had been watching a pair of Dickinson’s Kestrels Falco dickinsoni nesting for the past month, being in full view of the verandah of PSB’s house. The shore around this stretch of Lake Manze is edged with palm forest, 30 Short communications the dominant species being Hyphaene compressa, Borassus aethiopum and Combretum constrictum. Moving inland from this thin strip, it starts to open up to Acacia and Terminalia woodland. As we watched, a Grey Kestrel Falco ardosiaceus flew from the top of the B. aethio- pum clutching something in its talons, closely pursued by one of the pair of F. dickin- soni, screeching its protests as it flew. Theardosiaceus alighted in the fronds of another B. aethiopum and proceeded to consume what we could now see was a chick. During this time the dickinsoni sat on a nearby frond continuing to voice its distress. No record of F. ardosiaceus displaying nest-raiding behaviour could be found. In fact, Sinclair & Ryan (2003) suggest that interactions with F. dickinsoni may result in hybridization where the two species’ ranges overlap in southern DR Congo. Jenkins (2005) describes their diet as consisting mainly of and , but also rodents and small birds, sometimes supplemented with husks of Hyphaene petersiana. They further note that ardosiaceus may occasionally pursue birds and bats in aerial chases. We would therefore assume that our observation was simply an opportunistic event. However, on consuming its meal, the ardosiaceus proceeded to thoroughly search the crown of the same B. aethiopum, where we strongly suspected a pair of Red-necked Falcons F. chicquera had nested a few months previously. This suggests to us that this individual was actively searching for nests to raid. F. ardosiaceus and F. dickinsoni are thought to be largely allopatric, but having a contiguous range (Ferguson-Lees & Christie, 2001). In the Selous, we encounter dick- insoni very regularly and they are present in large numbers. Although we have found no confirmed nests of ardosiaceus, there are numerous old Scopus umbretta nests in the area, and these are known to be commonly utilized by breeding F. ardosia- ceus (Tarboton, 2011). Despite the lack of confirmed breeding in the area, our observa- tion of F. ardosiaceus on three other occasions at different times of year (two sightings in June 2013 and one in September 2013) would suggest that they are resident, if only in small numbers, and that the Selous is one area where the two species’ ranges over- lap. All these sightings have been in similar habitats — riverine palm forest or the ecotone between this and open Acacia/Terminalia woodland. References Ferguson-Lees, J. & Christie, D. A. 2001. Raptors of the world. London: Helm. Jenkins, A. R. in Hockey, P. A. R., Dean, W. R. J & Ryan, P. G. (eds) 2005. Roberts Birds of Southern Africa edition 7. Cape Town: John Voelcker Bird Book fund. Sinclair, I. & Ryan, P. 2003. Birds of Africa south of the Sahara. Johannesburg: Struik. Tarboton, W. 2011. Roberts nests and eggs of southern African birds. Cape Town: John Voelcker Bird Book Fund.

P.S. Bennett P.O. Box 2261, Dar es Salaam, Tanzania. Email: [email protected]

Scopus 37(1): 29–30, January 2017 Received 24 June 2014