Materials to biology of the Bittern and the Marsh Harrier in north-east of Ukraine. - V.T. Afanasyev. - Avifauna of Ukraine. 1. 1998. - P. 16-23.
Data were collected in north districts of Sumy region, north-east districts of Chernigiv region in 1958-1995. Some observations were made in the south of Bryansk region in Russia. Study area is situated in bassin of the Desna river. Some data on breeding ecology are presented. The full clutch contains in the Bittern as a rule 4-6 eggs (on average 4,2; n = 26), in the Marsh Harrier - 3-8 eggs (4,5; n = 99). Breeding places are described. 68,9 % of found nests of the harrier were situated in reed, 9,8 % - in bulrush, 5,3 % - in cat's tail, 9,1 % - in willow bushes, 6,8 % - on tops of reed (n = 132). It is noted frequent breeding of both species at a short distance. [Russian].
Key words: Bittern, Botaurus stellaris, Marsh Harrier, Circus aeruginosus, North-east Ukraine, breeding, nest, egg.