The decline of an urban Hooded Vulture Necrosyrtes monachus population in Dakar, Senegal, over 50 years
As in many West African cities, in Dakar Hooded Vultures Necrosyrtes monachus have always been characteristic urban scavengers. The recent decline of Hooded Vultures in other parts of Africa, mainly eastern Africa, has been the reason in 2015 for up-listing of its status by the IUCN in the Red List of Threatened Species to Critically Endangered. As the Hooded Vulture is still common in the Lower Casamance, Senegal, in the Western Region of The Gambia and in Guinea-Bissau, without clear signs of a recent decrease, a survey of its current status in Dakar was undertaken and compared with historical data over the past 50 years. A strong decrease of >85% was noted from 3 000 individuals in 1969 to 400 in 2016. This decline is on the high end of the decline noticed over much of its range but in striking contrast with the apparently stable populations along the West African coast more to the south (The Gambia to Guinea). Likely causes are (1) exponential urbanisation resulting in loss of feeding sites and reduced food availability, (2) increased poisoning of feral dogs with strychnine sulphate due to an upsurge of rabies and (3) increased disappearance of suitable trees for nesting and roosting.
Keywords: cutting of trees, Hooded Vulture, Necrosyrtes monachus, poisoning, population estimate, slaughterhouse sanitation, urban development