A new “practitioner’s perspectives” article in the Journal of Applied Ecology has called for a unified approach using standardized methods to monitor vultures for conservation purposes.
Paula Perrig and colleagues outline the challenges of designing and implementing robust monitoring programmes to gather reliable, unbiased data to inform strategies to inform the conservation of large vertebrates with slow life histories (i.e. long lives, low reproductive rates), such as vultures. These challenges include a lack of funding, limited expertise and practical difficulties of implementing some scientific methods in the field due to the vast and often inaccessible areas in which vultures live and breed.
The authors describe the precarious situation that many vulture populations are now in across the globe due to the multiple anthropogenic threats that they face and their vulnerability to toxins found in the carrion on which they feed. Fortunately, they state that it is now recognized “that ecological services provided by vultures are generally declining [which has] triggered global efforts to preserve them.”
While they acknowledge the success of many conservation actions such as reintroductions and increasing the supply of uncontaminated carrion at feeding sites, they also describe a “scarcity of coordinated efforts to monitor vulture populations.” The example that they use to illustrate that coordinated programmes for certain species do exist is that of the International Bearded Vulture Monitoring network (IBM) which is led by us here at the Vulture Conservation Foundation and implemented by multiple partners and associated organizations across Europe.
The article goes on to describe common techniques used to study vulture populations, and although they use the Andean condor as an example, all of these methods are already used by the us and our partners to study all four European vulture species. For example, the authors emphasize the need to develop genetic monitoring methods using shed feathers, something which started 20 years ago in the Alpine reintroduction project of the Bearded Vulture. All released birds are genotyped, moulted feathers are collected by the IBM partners across the whole distribution range. Special effort is taken to find a sample from the wild hatched fledglings. Most of the nest sites of Bearded Vultures are inaccessible or very difficult to reach and sampling the chick in the nest is often impossible. Other methods described in the article and used widely by our partners include capture-based methods for tracking and marking vultures; camera trap monitoring at feeding sites; and coordinated population censuses.
The call for “scientists and organizations focused on vulture conservation….to promote and use standardized monitoring programmes” is positive, and it is encouraging to know that VCF and the many partners across Europe are leading the way in the development of these methods to demonstrate the continuing success in their efforts to restore vulture populations across the continent.
Figure 1. Non -exhaustive review of methods used to study vulture populations (a) globally (b) by representative vulture species. See Supporting Information S1 for references. Figure 2. Comparison of sampling techniques used to monitor vulture populations based on data products [green; population size [N], proportion adult female s breeding [B], survival rate [S], sex ratio [M:F], and age ratio [A]), advantages (blue), disadvantages (red), and additional data generated (black) ] .