Ecology of Short-toed and Booted Eagles in the North of the Sumy and the South of the Bryansk Regions. Short-toed Eagle

V. T. Afanas’ev
Ukrainian Ornithological Society
The population of Short-toed Eagle began to increase since stop of Raptors shooting bonuses awarding in 1969. Now the summary number of breeding Short-toed Eagles in the northern regions of the Sumy Region is about 4-6 pairs and there are not more than 10 nesting pairs in the South of the Bryansk Region.
Short-toed Eagles inhabit old parts of pine or mixed forests, especially not far from moss bogs.
The average date of the spring arrival is March 27th. Usually at that period the snow yet lays on the ground in some places. Nesting zones are being occupied just after females incoming. In April, or sometimes in March, the breeding games can be observed.
Nests are situated on pines, near trunks or at a distance about 2-3 m from them. The nests are situated at 6 to 27 meters height. The same nest can be used 2-3 years on end, but if a pair has several nests they are being used in turn. Old pairs have 2-3 nests on their nesting zone, with a distance of 0.3-0.6 km between them.
The process of a nest building was monitored in detail in 1984. Birds built the nest at a height of 6 m from the ground and at a distance of 50 cm under the top of a pine, though there was a part of high pines at not more than 50 m away. The whole building process took about four weeks. Eagles carried building material from places about 2 km away. The egg was laid on May 6th, its size: 73.6 x 57.4 mm, weight: 128.0 g.
An unusual nesting was registered on May 05th 1994. The nest was situated on the ground on a not big dimple in a moss near the bottom of an oppressed pine at border of a bog. The female had leaved the nest because of the approaching of a man at a distance of 15-20 m. The single egg had been discovered in the nest. Its size and shape were atypical for Short-toed Eagle.
The beginning of the laying falls at the first days of May, with one exception in 1989 – April 18th. Apparently, both parents take part in the incubation, but a female spends more time in a nest. In contrast with the beginning of the incubation a female is less shy at the end, and sometimes allows very close approaching.
Both parents supply the young Short-toed Eagle with food. According to analysis of food remains, feeding is based on snakes, lizards, rodents, hedgehogs, frogs and passerines. After leaving of the nest a juvenile stays not far from the nesting zone during 4-6 weeks. Departure falls at September, apparently the adult fly away at first. The latest date of registration is October 9th 1996.