The paper presents data on nesting of the Great Cormorant on islands of Yeysky Liman. Two waves of increase in abundance of nesting birds are recorded: 3.5 times increase in 2007, and 2 times – in 2009. This growth in numbers is because of resettling cormorants from other nesting areas. The reasons induced changes of bird nesting areas are as follows: management of abundance, overpopulation, attractiveness of new places to the cormorant due to suitable habitats and rich forage reserves. In 2009, the cormorants started nesting on trees that is generally not typical for breeding cormorants in the Western Ciscaucasia. This fact is indirect evidence that birds may resettle from Ukrainian shore.