Background The imperial eagle is a rare and declining bird species, cited as a priority species by a number of international conventions. Its last remaining stronghold in Europe outside the former Soviet Union is the Carpathian Basin of Hungary and Slovakia. 55 pairs were known to breed in Hungary in 2001. The imperial eagle nests in both forested mountain ranges and in open, agricultural areas. However, it mainly feeds on hamsters, hares and sousliks, which means the species depends on extensively used, open agricultural landscapes. Contrary to the general tendency at European level, the eagle population of Hungary had increased over the previous decade. This is largely because former vast monocultures were replaced by smaller farms during the post-communist transition that started in 1990. As government subsidies for agricultural chemicals were cut significantly, the lack of capital meant that many privatised arable fields fell fallow. They then provided an ideal habitat for hamsters, hares and pheasants and rich hunting for eagles. However, the current abundance of fallow lands in the Hungarian plains seems likely to be just a temporary phenomenon, making the long-term prospect of the species rather insecure. Accession to the EU is generating significant land-use changes. Already, a new motorway is cutting through the project area and many potential eagle habitats are being transformed into tree plantations with EU financial support. Within the next years, recuperation of fallow lands and agricultural intensification might become the main problem for the imperial eagle. Objectives This first-ever LIFE-Nature project on the imperial eagle aimed to ensure that the most appropriate areas for the species in Hungary be designated as 'Special Protection Areas' under the Birds Directive. This aimed to support the ultimate objective of the long-term growth of the imperial eagle population To realise this, the project sought to decrease habitat loss, decrease individual mortality – in breeding areas, in temporary settlement areas and on migration routes – and raise public awareness of the species and the dangers it faces. To plan suitable actions effectively, the project sought first to develop a better understanding of what kind of agriculture or forestry is needed and what should and should not be done to promote imperial eagle numbers. It also aimed to understand where else, beside the breeding areas, action would be needed for the eagles. Planned activities included the search for additional nesting sites in the field and satellite tracking of tagged immature birds to provide data on nesting and foraging patterns. It was envisaged that this information would be used in developing management guidelines which, ultimately, should lead towards the development of conservation-oriented agri-environment schemes. The project also foresaw the insulation of dangerous power pylons to avoid the electrocution of birds and the construction of artificial nests. Direct surveillance of nests was to be an option at those nesting sites where human disturbance might be a risk factor. Results The project developed an ‘imperial eagle management plan’, which helped lead to an increased acceleration of population numbers – from 55 breeding pairs in 2001 to 73 in 2005. A proposal to include core breeding areas into the SPA network was prepared and sent to the Ministry of Environment. Successful monitoring activities included the fitting of 24 juvenile eagles with satellite-telemetry or radio tags and the recording of all activity in the nest of a lowland breeding pair with a nest camera system. The project mapped nearly 700 km² of imperial eagle habitat, focussing on areas surrounding nest sites. This research provided exceptional and new information on the preferences of the imperial eagle which enabled the project team to produce guidelines to encourage the development of the most suitable habitats for the bird. The comprehensive plan describes: the eagles' biological characteristics and ecological needs; the methods of delineation of priority areas; possibilities and requirements to maintain optimal breeding and foraging habitat; and the necessity of collaboration with the main stakeholder groups to maintain a healthy population of the species in all of its habitat types. To actively promote numbers of the bird, the project team constructed artificial nests and monitored breeding attempts, allowing for intervention when necessary. The team rescued eggs - and succeeded with artificial hatchings - reinforced collapsing nests and even destroyed nests before the breeding season to force adult pairs to move away from locations of great risk. Nest guarding to prevent human disturbance was organised in three (successful) cases and nine injured or weakened birds were taken to a vet of which five were able to be re-released. Surveys of 6,000 power lines found nearly 1,000 electrocution victims of 30 species, including four imperial eagles. The project started the process of retrofitting insulation covers onto all neighbouring power lines and led a campaign to call for the insulation of power lines to be made compulsory. Other information activities to raise awareness of key issues concerning the bird included a website, notice boards, publications, educational materials, workshops and public meetings.