SPATIAL ORGANIZATION OF BIRD POPULATION OF THE URUP AND ITURUP ISLANDS (KURIL ISLANDS)

Abstract

The ecological and geographical differentiation of the bird population at 18 sites of the Urup and Iturup islands was analyzed. The method of route accounting was applied. A total of 109 species were recorded, 62 of them on both islands. The coefficient of faunal commonality between the terrestrial habitats of the islands is 72%, and between the coastal-marine - 71%. The coefficient of similarity of the bird population between the land habitats of the islands is 36%, and between the coastal-marine - 29%. The values of bird population density on the islands are close both between terrestrial (610-757 ind./km2) and coastal-marine (536-607 ind./km2) habitats. The high population density is everywhere due to the abundance of numerically predominant species of the Far Eastern island and the Chinese fauna types. The total population of species of these faunas accounts for more than 50% of the population in terrestrial (282-469 ind./km2) and coastal marine (172-333 ind./km2) habitats. The spatio-temporal dynamics of the bird population is characteristic.