Poisoning and re-introduction of the Griffon Vulture Gyps fulvus in Kresna Gorge, Bulgaria 2017
The reintroduction of the Griffon Vulture Gyps fulvus in Kresna Gorge in south-western Bulgaria started in 2010 (Stoynov & Peshev 2011, 2012, 2013, 2014) and is run by the Fund for the Wild Flora and Fauna (FWFF). At present it is part of the project “Vultures Back to LIFE”. The number of wintering Griffon Vultures during the winter season 2016-2017 was a record high: 50 birds with some counts of over 60. About 10 pairs were showing breeding behaviour and at least four eggs were laid, until mid-March 2017 when the largest documented poisoning event of Griffon Vultures in the Balkan Peninsula occurred.
From 12 March 2017 to early April of that year, the bodies of 18 Griffon Vultures were found, and the missing and indirectly identified victims numbered more than 30 individuals. Although several cases of poison baits targeted to kill wolves were recorded near the villages of Stara Kresna, Krupnik and Tserovo, all the vultures were poisoned probably in the same place near the village of Tserovo over at least three consecutive stages. While small baits were used in the first two regions and affected mostly wolves, foxes, and dogs, in the area of Tserovo the poison was set in a carcass of a dead cow that remained an active bait on the ground for more than two weeks. Despite the wide media coverage and mass public response to this destruction of nature, law enforcement investigations did not result in any prosecutions.
The incident marked 2017 year as a catastrophe for the colony of Griffon Vultures in Kresna Gorge. Birds from other colonies were killed too: several birds from Vrachanski Balkan, including the first marked chick from a nest in the region, a bird from the Eastern Rhodopes and several from Macedonia and Serbia.
High levels of management effort, combined with an increasing knowledge of the species and applied by FWFF and related organizations, resulted in the Kresan Gorge colony reconsolidating and being sustained. The remaining five to eight birds, probably with memory of the colony of Kresna Gorge, were supported by the immediate release of six more Griffon Vultures and by the continuous provision of safe food at vulture feeding sites. By the end of 2017, the local group of vultures ranged in size between 15 and 35 birds. For the monitoring and possible prevention of poisoning, the use of precise and intensive data collection via satellite transmitters was introduced.