One of the primary goals of conservation translocation programs should be the maintenance of both population demographic stability and genetic diversity. Here, we provide genetic management ...recommendations to inform a population reinforcement of the declining Egyptian Vulture population in the Balkans. Specifically, we examined whether the number of released individuals is sufficient to prevent genetic diversity loss due to random genetic drift and what the origin of the individuals should be that comprise the captive breeding pool. To this aim, we estimated and assessed genetic diversity levels and genetic structure of Egyptian Vulture populations across much of the species’ range using both neutral and non-neutral candidate loci involved in migration. We then evaluated the effects of the currently proposed population management scheme and candidate source populations on retaining allelic diversity. Our results show low differentiation values among populations and absence of genetic structure which point to past high gene flow. Furthermore, there was no predicted significant impact of different source populations on the genetic diversity of the recipient Balkan population. We also found that the declining Egyptian Vulture population in the Balkans still retains high levels of genetic diversity and therefore genetic diversity restoration is not currently needed. However, without any management, diversity is likely to decrease fast because of increased genetic drift as the population size continues to decline. Population reinforcement with nine birds per year for 20 years would provide sufficient demographic support for the population to retain > 85% of rare allelic diversity. Birds originating from the Balkans would ensure ecological and behavioral similarity and thus would be the best option for reinforcement. Nevertheless, our results demonstrate that to prevent further population contraction and loss of adaptive alleles, releasing individuals of different origin would also be appropriate.
The Goosander
was not recorded breeding in Bulgaria till recently. We present herewith the very first record of the species breeding in the country and estimate the size of its breeding population in ...Bulgaria. Thus, we propose a change in its status in the country with more effort to be invested in the survey of this small, isolated population.
The Egyptian Vulture (Neophron percnopterus) has been classified as 'Endangered' due to rapid population declines across its range. Thus, exhaustive studies on its demography may serve as an ...important stepping stones for successful conservation programs. Breeding performance is one of the main components of the demography of a raptor population. Evaluating reproductive rates is easier than other demographic parameters, while remaining a very useful metric to identify factors driving raptor population trends. Here we present the breeding performance of the species' population in Bulgaria as a result of a long-term monitoring (2005-2016). The studied population shows high breeding performance, based on a breeding success (1.11 ±0.13 fledglings / laying pairs), productivity (0.88 ±0.1 fledglings / occupied territories) and fledgling success (1.2 ±0.1 fledglings / successful pairs), all among the highest recorded in Europe. Pairs breeding in territories with high occupancy rate produced 88% of the fledglings. However, over the last 14 years the Egyptian Vulture population in Bulgaria has declined with 51.7%. We discuss the causes underlying these results and recommend the implementation of conservation measures on a larger scale in order to secure the survival of the species in the country.
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