Only one vulture was detected during transect surveys in northern Nigeria.

Abstract

Vulture and raptor populations have declined across West Africa during recent decades due to numerous and widespread anthropogenic threats. To estimate encounter rates of vultures and raptors in northern Nigeria, we conducted a total of 248 km driven transects on 195 km and 53 km of paved and unpaved roads, respectively. We also conducted walked surveys beneath 79 km of power transmission lines to search for dead vultures and raptors; and visited 12 abattoirs, 11 slaughterhouses, and 12 dumpsites to assess the occurrence of vultures and raptors. All fieldwork was done between October and December 2018. Overall, 357 individuals of 23 species were detected, most of which were recorded at low encounter rates. Only one Hooded Vulture Necrosyrtes monachus was recorded across all surveys, and no other vulture species were seen. Yellow-billed Kite Milvus aegyptius, Grasshopper Buzzard Butastur rufipennis, and Black-winged Kite Elanus caeruleus had the highest encounter rates of 0.351, 0.262, and 0.189 individuals km-1, respectively. In contrast, the largest raptor species, Booted Eagle Hieraaetus pennatus, Short-toed Snake Eagle Circaetus gallicus, Beaudouin's Snake-eagle, and Bateleur Terathopius ecaudatus had the lowest encounter rate of 0.004 individuals km-1 (one individual each). No dead vultures or raptors were found during the walked surveys beneath power lines. Although historical data about vulture and raptor distribution and abundance in northern Nigeria are limited, our results show an apparent absence of vultures from the wider landscape and a low density of raptors. Support among local stakeholders for the conservation of vultures and raptors should be encouraged through wider dissemination of information about the importance of these birds, as well as stronger deterrents again illegal killing and trade.