Ten more griffon vultures (nine adults and one immature) were fitted with satellite transmitters at the end of May, as part of the LIFE Re Vultures, to provide us with critical data on the use of space, their dispersal and migration, and possible threats. The griffons were also fitted with colour-rings and numbered wing tags, while blood and biological samples were collected.
In total 25 griffon vultures were trapped in the walk-in-trap built by the project team in Studen Kladenets, near one of their breeding colonies in the Bulgarian Rhodope Mountains. All of the birds were marked with standard wing tags (blue wing tag + orange digits), PVC rings (green ring +white digits) and metal rings, and 10 of the birds were equipped with GSM/GPRS transmitters. Last year, another 7 griffon vultures – four adults and three young – and 11 black vultures had already been fitted with tags by the LIFE Re Vultures team.
This is one of the actions within the LIFE project “Conservation of Black and Griffon vultures in the cross-border Rhodope Mountains”, led by Rewilding Europe in partnership with Rewilding Rhodopes Foundation, Bulgarian Society for the Protection of Birds, WWF Greece, the Vulture Conservation Foundation and the Hellenic Ornithological Society. The project aims to recover and further expand the black and griffon vulture populations in this part of the Balkans, mainly by improving natural prey availability and reducing mortality factors such as poaching, poisoning and electrocution and collision with power lines.
Although black vultures are increasing in Western Europe (Portugal-Spain-France), there is only one colony left in the whole of the Balkans, in the Dadia Forest, in the Greek part of the Rhodope Mountains. This project will serve to enhance the conservation of this population, and will also contribute to the conservation of the main griffon vulture colonies in Bulgaria.
To achieve this, many actions are being implemented, including tagging of vultures, increasing their food availability through releases of wild ungulates and the establishment of supplementary feeding points, using a trained dog unit to locate poison baits, and insulating power line poles and mounting bird diverters to avoid collision.
The Bulgarian part of the Rhodope Mountains is an important part of home range of black vultures breeding in Dadia, but also a possible site where immature birds may settle and start breeding. The tracking information from black vultures will help the team to identify suitable places for building artificial nests on the Bulgarian side, stimulating birds to start another colony here. Last year the team constructed the first artificial nests to attract the birds, placed in locations identified by computer models, based on current knowledge. Additional information that will come from the satellite transmitters is now feeding the computer models to identify potential breeding locations. Over the last few months several black vultures have been seen in the Bulgarian Rhodopes, usually in the supplementary feeding points established by the project.