Sustaining Increasing Wintering Raptor Populations in Central Israel: A 38 Years Perspective

Abstract

Censusing wintering raptors has proved useful in detecting changes in populations. Israel is a well-known bottleneck for soaring birds in the autumn and the spring. Despite the many studies on migratory raptors in Israel, none have undertaken the study of the overwintering raptors consistently over extended periods, such as 1985–2022, a period of 38 years. During the study, conducted in central Israel, we recorded 44,120 individuals from 32 species. The most frequently observed species were Black Kite (Milvus migrans; 59.1%), Common Kestrel (Falco tinnunculus; 18.1%), and Steppe Buzzard (Buteo vulpinus; 6.6%). We found an increase in the total number of individuals, where the mean increase compared to the starting year was 851.6 ± 1071.2%, and the average annual growth was 43.7 ± 158.8%, respectively. A similar pattern was found in the number of species during the study period, where the mean annual increase was 17.1 ± 20.5%, and the average annual growth rate of species richness was 2.2 ± 16.2%. However, an evaluation of the mortality from power lines of two listed species suggests that the wintering raptors are not well protected in the study area. The conservation of these raptors and the possible sustainability of their wintering populations into the future, some of which are on the IUCN Red List, are of great importance, and the authorities should try and understand the human demographics and mesohabitat changes that appear to influence the wintering capabilities of the raptor populations.