Eurasian Bittern

Botaurus stellaris (Linnaeus, 1758)

2015-05-06 Ushsart village	© Timur Iskakov

Description

Background color of Great Bittern is clayey-buff; each feather is black-brown mottled. Forehed, crown and nape are black-brownish. There are no differences in seasonal and age plumages. Bill, legs and skin near eyes are greenish-yellow; legs are slightly greener than bill; claws are black-brown, eyes are yellow. Sizes: wing 320-350, tail 113-116, tarsus 96-102 mm.

Distribution

Eurasian Bittern widespread breeds on lakes and reservoirs of Kazakhstan plains. On migration it also observed on plains; very rare visits mountain lakes (Markakol lake) and foothills of Western Tien Shan (14 October 1978). In small numbers Eurasian Bittern winters to the south of Baygakum, Turkestan and Shymkent.

Biology

The Eurasian Bittern is common breeding migrant. It inhabits lakes and weak current rivers with plentiful reed-beds, mace-reed and cane. Appears early (identified by voice), at early March - mid-April (at Semipalatinsk in second half of April - early May) Migrates singly, rare in pairs. Nest is built among reed-beds from reed stems and leaves. Birds continue to construct the nest during incubation and raising of juveniles. Clutches usually 3-5, rarely 6 eggs, which found in mid - end May. Just hatched juveniles found mid-June - mid-July; flying young observed mid-July - August. Courtship booming of males heard till to early July. Repeated breeding after loss of clutches is possible. Autumn migration (singly or in small flocks of 3-8 birds) begins at end of August, majority of birds departs in September - October; single birds recorded in mid-November.

Subspecies

References

"Птицы Казахстана" том 1. "Наука". Алма-Ата, 1960. Э.И.Гаврилов. "Фауна и распространение птиц Казахстана". Алматы, 1999. Gavrilov E. I., Gavrilov A. E. "The Birds of Kazakhstan". Almaty, 2005.