Reproduction parameters, diet composition and interactions with some raptor species in the increasing White-tailed Eagle (Haliaeetus albicilla)

In the twentieth century many raptors in Europe decreased due to habitat degradation, use of the organochlorine pesticide, industrial pollution, and deliberate killing by humans. Over the last decades, many populations of raptors have been recovering as a result of the implementation of various conservation programmes and have spread in previously abandoned areas. The aim was to study the breeding performance of recovered and increasing population of the White-tailed Eagle (Haliaeetus albicilla), diet composition and interactions with some raptor species. The data for this study were collected by the author between 1997 and 2020 from two research areas, but for each task the dataset used varied depending on the course of research. The study results indicated that breeding performance of the White-tailed Eagle pairs did not differ among habitats and did not decline with an increase in the density of nesting pairs. During the breeding season, fish and water birds were the most common prey and key prey species was the Northern Pike. The species composition of the prey varied among pairs reproducing in different habitats, but the White-tailed Eagle, despite its increasing population, was not limited by the abundance of prey in the environment. The impact of the White-tailed Eagle on internationally protected bird species during the breeding season was insignificant. Adult raptors were rare White-tailed Eagle prey; however, nestlings of the Common Buzzard were more frequent as a prey. The larger-bodied White-tailed Eagle has a no effect on the smaller-bodied Lesser Spotted Eagle reproduction and its local population dynamics in a region where both species were abundant