Present state and breeding ecology of the Goshawk in Belarus. - V.V. Ivanovsky.
- Berkut. 5 (2). 1996. P. 137-140.
Data were collected in Vitebsk region in 1973-1994. 90 nests of the Goshawk were examined. 36,9 % of nests were found in mixed forests, 24,7 % - in pine forests, 24,7 % - in fir forests, 9,6 % - in aspen forests, 2,7 % - in birch forests, 1,4 % - in alder forests (n = 73). One pair may have 1-4 nests (on average 1,4 ones). The height of nest placing fluctuates from 4,5 to 22,0 m (on average 12,5 m). Diameter of them is 0,6-1,2 m (on average 0,95 m). 55 % of nests were built on the furcation of main trunk, other ones - on side branches. Directly near nests birds can be seen since early March. Egg laying starts between 10.04 and 17.04. The clutch has from 2 to 4 eggs, the mean clutch size is 3,6 eggs (n = 26). Egg measure: maximum - 64,8 x 47,0 and 59,8 x 49,3; minimum - 50,4 x 45,0 and 63,7 x 41,0; mean - 59,7 x 46,1 mm (n = 67). Chicks hatch on 16-20.05. Breeding success is given in the Table 1. Fledglings live nests on 22-28.06. 99 birds were ringed, 9 recoveries were received (9,1 %). All the recoveries from fledged youngs were received during August from nesting places or some to the South. All the ringed goshawks, found in Vitebsk region in autumn and winter, were from Finland. The main causes of death of the Goshawk in Vitebsk region are shooting and loss on electric lines. Trophic links are given in the Table 2 and Fig. 2. 95,7 % of the Goshawk's prey during the breeding period make birds. The base of feeding are corvines, pigeons and Galliformes. In autumn and winter feeding is more monotonous. The part of poultry (to 15,8 %) and rodents (to 13,2 %) increases. Separate pairs of the Goshawk have the narrow specialization in feeding on rooks (40-80 %), pigeons (40-60 %), grouses (20-30 %) or mammals of the middle size (squirrel, hare) - 10-20 %. The special study has shown the little or very little influence of the Goshawk on populations of its prey. Last years number of this species some decreased. At present its breeding density in Northern Belarus is on average 6,6 pairs/100 km2. [Russian].
Key words: Goshawk, Accipiter gentilis, Belarus, ecology, breeding, phenology, habitat, nest, clutch, breeding success, feeding.