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Supplementary feeding sites make considerable contributions to vulture food requirements but likely also expose vultures to risks

3 Jul 2020 - 12:00
Photo credit: Christiaan Brink

 

A new study led by researchers at the FitzPatrick Institute of African Ornithology, University of Cape Town, investigates the use of vulture supplementary feeding sites (SFS), also known as vulture restaurants, as a conservation tool in South Africa. Two papers from this study have been published this year. One, that examines the distribution and provisioning rates of these SFS, has been published in Animal Conservation (https://doi:10.1111/acv.12561), and another, examining SFS manager’s perceptions and awareness of best management practices, has been published in Conservation Science and Practice (https://doi:10.1111/csp2.237).

Vultures are currently one of the most threatened groups of birds in the world and nine out of eleven of the vulture species that occur in Africa are classified as endangered or critically endangered. Since the 1970’s SFS have been a popular method used to attempt to curb vulture declines in South Africa. It is thought that by providing a safe and reliable food resource vulture breeding success and survival can be increased. The main driver of vulture declines is poisoning, either unintentionally through livestock farmers using poisoned carcasses to target predators, or intentionally, by poachers wishing to keep their activities secret or people harvesting vultures for belief-based use. The provisioning of safe food at SFS is proposed to reduce the risks of vultures encountering such poisoned carcasses. Based on these assumptions, conservation organisations have been motivating livestock farmers and meat producers to provide unwanted carcasses and meat for vultures. The positive effects of SFS on vultures are, however, still debated and there are potential negative consequences that need to be considered.

Through the coalition of existing data and interviewing all known SFS managers in South Africa, our researchers (in collaboration with  VULPro, Ezemvelo KwaZulu Natal Wildlife and the Endangered Wildlife Trust) have established a new updated National SFS Database which can be used to verify the proposed positive effects of SFS and investigate potential trade-offs. Most importantly, this database now includes information on how much food is being provided by each SFS, crucial information for determining their effects. “We estimate that 3301 tonnes of food is provided at these sites for vultures every year, this equates to roughly 83% of the food requirements of the entire South African vulture population”, says lead author Christiaan W. Brink, “The most commonly provided meat types are beef, pork and game and most of the provisioning is happening in Limpopo, North West and KwaZulu Natal.”

Due to the widespread use of SFS and the considerable amount of food that is being provided, SFS have the potential to have significant effects on the vulture population if not managed according to best practices. The researchers therefor wanted to understand the context in which these SFS are run and if they adhered to best management practices, they questioned managers accordingly. Most managers believed that they benefitted from running a SFS, most commonly in the form of the free cleaning service provided by the vultures (unsurprisingly most SFS managers were involved in livestock farming). Unfortunately, awareness of vulture threats were generally low, a situation that may expose vultures to unnecessary risks. For instance, less than half of the managers identified the afore mentioned unintentional poisoning as a major threat to vultures. Furthermore, only 11% of managers that provide game meat indicated that they avoided providing lead contaminated carcasses for vultures. Lead from spent ammunition in carcasses has been shown to cause lead-poisoning in vultures. Low awareness of these threats and others mean that managers are less likely to adhere to best management practices such as ensuring that the food provided at SFS are safe for vultures to eat. “Our study has shown that there is an urgent need for increased interaction between SFS managers and conservation practitioners”, said Christiaan, “Although this conservation tool has a lot of potential to be usefully employed for the conservation of vultures, further research is required to understand what effects it is having on vulture populations and behaviour. Motivating for the general use of this practice, without the proper dissemination of best management practices, can put vultures at risk.”