The great cormorant Phalacrocorax carbo - a new breeding species in the Selenga river delta (lake Baikal)

In 2013, a breeding of Great Cormorant Phalacrocorax carbo sinensis was first discovered in the Selenga River delta at Lake Baikal, namely in the central part of the delta in a colony of Grey Heron Ardea cinerea. The number of cormorants was increasing from several tens of pairs in 2013 to 610-630 pairs in 2015. This fast increase went by the expansion of cormorants in the heronry, with a pushing out the herons. It is the only colony of cormorants in the delta. The general number of cormorants in the Selenga delta was estimated as c. 1.6-2.0 thousand birds (with breeders and nonbreeders but without fledglings). Amur Sleeper Perccottus glenii, which was inadvertently introduced in the basin of Selenga River in 1970s and got numerous in its delta in 1980s, appears to be the main food of cormorants in June.