reintroduction

Fifty years after presumably becoming extinct as a breeding species in Bulgaria, the Griffon Vulture, one of the largest birds of prey in Europe, is back in the Eastern Balkan Mountains. Since 2009, three local conservation NGOs – Green Balkans – Stara Zagora, the Fund for Wild Flora and Fauna and the Birds of Prey Protection Society, have been working on a long-term restoration programme to bring vultures back to their former breeding range in Bulgaria. The programme is supported by the Vulture Conservation Foundation, the Government of Extremadura, Spain, and EuroNatur. Its results have been described in the open-access, peer-reviewed Biodiversity Data Journal.

*Griffon Vultures in Eastern Balkan Mountains. Photo by Hristo Peshev, fwff.org*

Two large-scale projects funded by the EU’s LIFE tool, one of them ongoing, facilitate the import of captive-bred or recovered vultures from Spain, France and zoos and rehabilitation centres across Europe. Birds are then accommodated in special acclimatization aviaries, individually tagged and released into the wild from five release sites in Bulgaria. Using this method, a total of 153 Griffon Vultures were released between 2009 and 2020 from two adaptation aviaries in the Kotlenska Planina Special Protection Area and the Sinite Kamani Nature Park in the Eastern Balkan Mountains of Bulgaria.

After some 50 years of absence, the very first successful reproduction in the area was reported as early as 2016. Now, as of December 2020, the local population consists of more than 80 permanently present individuals, among them about 25 breeding pairs, and has already produced a total of 31-33 chicks successfully fledged into the wild.

*Vulture tagging. Photo by* *Hristo Peshev, fwff.org*

“Why vultures of all creatures? Because they were exterminated, yet provide an amazing service for people and healthy ecosystems”, Elena Kmetova-Biro, initial project manager for the Green Balkans NGO explains.

*Vulture tagging. Photo by* *Green Balkans, www.greenbalkans.org*

“We have lost about a third of the vultures set free in that site, mostly due to electrocution shortly after release. The birds predominantly forage on feeding sites, where the team provides dead domestic animals collected from local owners and slaughterhouses,” the researchers say.

“We, however, consider the establishment phase of the reintroduction of Griffon Vulture in this particular site as successfully completed. The population is still dependent on conservation measures (supplementary feeding, isolation of dangerous power lines and accidental poisoning prevention), but the area of the Eastern Balkan Mountains can currently be regarded as a one of the only seven existing general areas for the species in the mainland Balkan Peninsula and one of the five which serve as population source sites”.

*Vulture adaptation aviary. Photo by Green Balkans, www.greenbalkans.org*

Original source: Kmetova–Biro E, Stoynov E, Ivanov I, Peshev H, Marin S, Bonchev L, Stoev IP, Stoyanov G, Nikolova Z, Vangelova N, Parvanov D, Grozdanov A (2021) Re-introduction of Griffon Vulture (Gyps fulvus) in the Eastern Balkan Mountains, Bulgaria – completion of the establishment phase 2010-2020. Biodiversity Data Journal 9: e66363. https://doi.org/10.3897/BDJ.9.e66363

The Saker Falcon (Falco cherrug) is a bird of prey living in plains and forest-steppes in the West and semi-desert montane plateaus and cliffs in the East. The majority of its Central and Eastern European population is migratory and spends winters in the Mediterranean, the Near East and East Africa. With its global population estimated at 6,100-14,900 breeding pairs, the species is considered endangered according to the IUCN Red List.

In Bulgaria, the Saker Falcon, considered extinct as a breeding species since the early 2000s, was recovered in 2018 with the discovery of the first active nest from its new history in Bulgaria. The nest is built by two birds that were reintroduced back in 2015 as part of the first ever Saker Falcon reintroduction programme. The results of the 5-year programme are described in detail in the open-access, peer-reviewed Biodiversity Data Journal.

Saker falcon, Bulgaria

Many factors contributed to the decline of the Saker Falcon in Bulgaria and globally, and most of them are human-caused. Populations lost big parts of their habitat due to changes in land use – the transition from grazing to arable crops led to the diminishing of key food sources. Other reasons include the use of poisonous baits and the accumulation of pesticides in the food chain, illegal trade of nest-poached chicks and eggs, power line electrocution, and lack of suitable nesting places.

Even after European legislation for the protection of wildlife was implemented, and regulations were issued on the use of pesticides in Bulgaria, the Saker Falcon population did not stabilise. Its endangered status further prompted joint conservation efforts between NGOs and national authorities.

As a result, a re-introduction programme for the Saker Falcon in Bulgaria was initiated in 2015, aiming to release a number of birds over a certain period of time using adaptation aviaries, or hacks. The Green Balkans Wildlife Rehabilitation and Breeding Centre (WRBC) in Stara Zagora facilitated the captive breeding of a group of Saker Falcons imported from Austria, Hungary, Germany, Slovakia and Poland by constructing ten breeding aviaries and two stock cages for juvenile falcons and equipping them with internal surveillance cameras.

Between 2015 and 2020, a total of 80 Saker Falcons – 27 females and 53 males, were released via the hacking method from four aviaries near the town of Stara Zagora. Out of them, 64 had been bred and hatched at the WRBC.

Observation records from 2018 confirmed that at least one pair of the falcons released in 2015 was currently breeding in the wild in Bulgaria. This observation proves that with the help of hacking, Sakers can survive in the wild until maturity, return to the region of their release and breed successfully. In 2020, the female bird in the breeding pair was changed with a Saker Falcon released in 2016, and the new pair bred successfully.

In 2020, the programme was restarted for another 5 years, with the aim to release 100 Saker Falcons and have six pairs breeding in the wild. This will help restore the Saker Falcon population in the southern Balkans and facilitate gene flow amongst fragmented populations from Central Europe to Kazakhstan.

Helping this iconic species successfully establish a self-sustaining population in Bulgaria has profound implications for conservation in the country – not only in terms of public awareness of species conservation, but also as an indicator of wider environmental issues.

Original source:

Lazarova I, Petrov R, Andonova Y, Klisurov I, Dixon A (2021) Re-introduction of the Saker Falcon (Falco cherrug) in Bulgaria – preliminary results from the ongoing establishment phase by 2020. Biodiversity Data Journal 9: e63729. https://doi.org/10.3897/BDJ.9.e63729

Tag: reintroduction

The incredible return of Griffon Vulture to Bulgaria’s Eastern Balkan Mountains

When conservation work pays off: After 20 years, the Saker Falcon breeds again in Bulgaria