Taylor and Francis Group, Ostrich: Journal of African Ornithology, 1-2(72), p. 96-100, 2001
DOI: 10.2989/00306520109485291
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Roadside counts of raptors in the southwestern and southern Cape during 1997/98 were compared with data from the 1950s and 1960s. Steppe Buzzard Buteo b. vulpinus, Black-shouldered Kite, Elanus caeruleus, and Yellow-billed Kite, Milvus (migrans) parasitus, opportunistic species preferring human-modified habitat, increased 3-22-fold. Steppe Buzzards furthermore increased proportionately from 25-31% to 60% of the observed raptor population in summer. The globally threatened Lesser Kestrel, Falco naumanni, which underwent a large decline during this period, was recorded 2-5 times mare frequently now than 35 years ago. Records of Rock Kestrel, Falco tinnunculus, Lanner Falcon, Falco biarmicus, and Booted Eagle, Hieraaetus pennatus, also increased. The data on most other species were too limited to be conclusive, but the total number of species observed increased from 15 to 20, despite the fact that the total mileage during this study was only about 20% of the mileage travelled on similar surveys in the 1960s. The results indicate that, although raptor abundance in this area has increased during the last three decades, opportunistic generalists have increased while specialists of indigenous habitat have not, or not to the same extent; this is of conservation concern.