Israel's breeding avifauna: A century of dramatic change

During the course of the 20th century many changes took place in the area encompassing Israel and the Palestinian Authority (hereafter Israel; ca. 28,000km ²): the human population grew from ca. 650,000 inhabitants during 1900-1903 (Rupin, 1920) to ca. 10 million in 2008, i.e. a 16-fold increase. This population increase was accompanied by an increase in land use for human needs - agriculture, aquaculture, forestry, construction of buildings and roads, etc., and a dramatic rise in the standard of living.Here we compare the status (distribution and abundance) of the 227 bird species that are breeding or have bred in Israel from the beginning of the 20th century to the present day. For each species we documented the environmental factors presumed to have affected it, and examined the effects of taxonomic order, body mass, diet, world and local distribution and nest location on the status of the avifauna. We found that 73.6% of the bird species breeding in Israel had undergone a change in their status during the studied period. While several of the examined factors were significantly related to the observed changes, some of them were also interrelated to some degree, making it difficult to single out the factor responsible for a particular change. The main reasons for the changes were nonetheless assessed as habitat change, introduction of invasive species and poisoning. Habitat change had many forms, most of which are related to agriculture, including irrigation, aquaculture and construction of water reservoirs; but also included afforestation, preservation of the natural forest, urbanization, gardening and the introduction of exotic plants. Habitat change was responsible for a population decline in 64 species and population increase in 62 species. Thirteen species, mostly Falconiformes, were impacted by poisoning. Sixteen invasive species, all of tropical origin, were introduced, of which seven were Psittaciformes. Although changes occurred throughout the country, the birds inhabiting the Mediterranean region were more affected than those inhabiting the desert region, reflecting the denser human population in the former region.