The Northern Goshawk, Accipiter gentilis, is a medium-large bird of prey in the family Accipitridae, which also includes other diurnal raptors, such as eagles, buzzards and harriers.
It is a widespread species that inhabits the temperate parts of the northern hemisphere. In Europe and North America, where there is only one goshawk, it is often referred to as simply the "Goshawk". It is mainly resident, but birds from colder regions migrate south for the winter.
In the spring breeding season, Northern Goshawks perform a spectacular "undulating flight display", and this is one of the best times to see this secretive forest bird. At this time, the surprisingly gull-like call of this bird is sometimes heard. Adults return to their nesting territories by March or April and begin laying eggs in April or May. Territories often encompass a variety of habitats, however the immediate nest area is often found in a mature or old-growth forest. The clutch size is usually 2 to 4, but anywhere from 1 to 5 eggs may be laid. The eggs average 59 × 45 mm and weigh about 60 g . The incubation period can range from 28 to 38 days. The young leave the nest after about 35 days and start trying to fly another 10 days later. The young may remain in their parents' territory for up to a year of age.
Source: en.wikipedia.org/wiki/Northern_Goshawk - 20.09.2011
This Northern Goshawk is identifiable as a squab by the design of the plumage and the light yellow iris.