Species conservation


Imperial eagle

The Imperial Eagle (Aquila heliaca) is a globally threatened species. It is listed in Annex I to the Birds Directive, Appendix III to the Bern Convention, the Bonn Convention, and the Red Data Book of Bulgaria.

Once widely distributed, today the number of the Imperial Eagle is estimated at about 30-35 pairs. There are not more than 20 known nests, as most of them are concentrated in the area of the Sakar Mountains and the Dervent Heights.

What we do

Green Balkans has been working for the monitoring, studying, and conservation of the Imperial Eagle in Bulgaria since 1980s, when the first two breeding pairs in the Sakar region were found. Today, our efforts are focused mainly on the following activities:

- studying and regular monitoring of all known nests;
- expeditions for localizing new nests of Imperial Eagle, studying the areas suitable for breeding, and identifying the limiting factors;
- guarding and monitoring of endangered nests during the breeding period in order to prevent egg robbing and chick poaching, disturbance of birds, as well as felling of trees, where nests are built. The monitoring provides valuable scientific information about the species’ behavior and ecology, which is of huge significance for its conservation.
- rescuing Imperial Eagles in distress and applying follow-up treatment and recovery at the Wildlife Rehabilitation and Breeding Center;
- afforestation – tree planting helps to overcome one of the main factors limiting the species’ distribution – lack of trees suitable for nesting. Usually, afforestation is done with poplar saplings and other native species.
- placing artificial nests – the experience in other countries shows that artificial nests help to attract birds to start breeding in a particular region;
- designating new protected areas and including the habitats of the Imperial Eagle in the NATURA 2000 Ecological Network;
- tagging Imperial Eagles with radio and GPS transmitters to track their movements and migration;
- educational campaigns involving local people – raising the ecological awareness of the people living in the regions, where a particular species is subject to conservation measures, is of crucial significance. Green Balkans implements numerous meetings and presentations related to the conservation of the Imperial Eagle, involving local people, authorities, and schools;
- placing information signboards – the signboards help to understand the importance of the Imperial Eagle and its habitats;
- publications – the Organization develops various information and promotion materials (posters, brochures, stickers, and T-shirts) related to the Imperial Eagle. These materials help to secure the public support for the conservation measures related to the species;
- implementing scientific studies on the species’ food specter, biology, ecology, and behavior;
- implementing an ANTI-POISON program to prevent the illegal use of poisonous baits against terrestrial predators.


The first nests in the Sakar region were found by Green Balkans’ specialists in the period 1986-89. Since then, as a result of the guarding and feeding implemented by volunteers of Green Balkans and BSPB, the breeding population tripled, reaching 20 pairs.

As a result of the consistent work, as well as the good cooperation with BSPB, the Regional Inspectorates of Environment and Waters, and the Forestry Departments, the Imperial Eagle population has been stabilized, as the trends for the past years show increased number of birds.

• Dozens of expeditions were carried out to find new nests and study the species’ habitat.
• In the period 2005–2007 more than 600 man-days of voluntary efforts were contributed to the guarding of nests during the breeding season.
• Almost 1,000 trees were planted to provide future opportunities for breeding.
• For the first time in Bulgaria, Green Balkans’ team implemented artificial feeding of eagles – this is a well-established practice that raises the breeding success of some pairs.
• Ten artificial nests were placed in the Sakar region and the Dervent Heights.
• In order to preserve the species’ breeding habitats, Green Balkans together with BSPB proposed the designation of two protected areas; 6 sites were included in the NATURA 2000 network, as the main priority is conservation of the Imperial Eagle and its habitats.
• In 2007, for the first time in Bulgaria, Imperial Eagles were tagged with radio and GPS transmitters to track their movements and migration.
• More than 100 presentations and meetings with local people and students were carried out, three information publications were produced, and three information sign-boards were placed.
• Two publications were produced – a scientific one on the food specter of the Imperial Eagle, and another one dealing with the species’ distribution in Bulgaria published in partnership with BSPB.

How you can help
- By taking part in the guarding of nests during the breeding period (April-August).
- By signalizing of any case of encroachment upon eagles – poaching or illegal use of poisons.
- By disseminating promotional materials related to the Imperial Eagle.
- By making a donation for the conservation of this species
- By participating in afforestation actions, placing of artificial nests, and other conservation activities.

Our activities for the conservation of the Imperial Eagle are implemented with the financial support of the People’s Trust for Endangered Species, EURONATUR, CBD Habitat, Vogelpark Walsrode Fonds e.V.