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Conservation genetics of threatened bird species

Final Report Summary - AVICONGEN2 (Conservation genetics of threatened bird species)

Human activities threaten many species worldwide and science-based conservation activities have an increasing importance. Current project integrated genetic methods into the population studies of threatened bird species, such as the Black Stork, the the Greater and the Lesser Spotted Eagle and the White-tailed Eagle. The project included several fields of conservation genetics, such as estimation of genetic variability within and between populations, gene flow between and within the species, population structure, population turnover and sex ratio.

Only partial isolation barrier has been developed between the Greater and the Lesser Spotted Eagles. Hybridisation is rather frequent and the hybrid zone is exceptionally wide in spotted eagles. Moreover, the hybridisation poses nowadays a serious threat to the globally vulnerable Greater Spotted Eagle. However, despite the smaller global population size, the European population of the Greater Spotted Eagle is more diverse and more structured than that of the Lesser Spotted Eagle. Studies on historical genetic diversity and long-term temporal processes in spotted eagles, as well in the Black Stork, are in progress. Estonian white-tailed eagle population has rather high genetic diversity, compared to the other European populations. Ringing records have demonstrated rather high migration rate between different regions within Estonia, resulting the lack of divergence between the contemporary western and eastern populations.

Recruitment of new individuals in the Greater Spotted Eagle, and probably in the Black Stork as well, is very low. However, the annual mortality in adult spotted eagles is higher than in the Black Stork and losses happen usually on migration.
Although the nestling ratio is equal in all studied species, adult sex ratio seems to be unbalanced in the Black Stork.

The outcomes of the project have increased the general knowledge about the long-lived bird species but it also will have applied implications. The results will be used in planning the further conservation actions for these threatened species, for instance in compilation of the action plans both in national and European level.