Members of the genus Accipiter are small and medium-sized hawks, often called Sparrow-hawks or Goshawks. The females are almost invariably much larger than the males – in some cases weighing twice as much – a level of size dimorphism only exceptionally reached in any other genus Falconiformes. Their wings are short and rounded; the tail usually quite long. They are well adapted for flying through dense bush. Bird-catching Sparrow-hawks generally have long and slender legs, with slender digits, the middle one being especially long. Goshawks are usually larger, with shorter, thicker tarsi and digits and a shorter middle digit. Some smaller species have goshawk-like feet and vice versa, making it difficult on a world-wide basis to subdivide the genus on this or any other broad basis. Although many accipiters feed upon birds moreso than do other hawks, some species take many mammals, especially squirrels; others take lizards, frogs, snakes, insects, even snails. In these species the legs and digits are sometimes slender, but short. Accipiters are rarely crested, but some have very attractive colour patterns. Black phases are present, especially in the tropical species. One in Australia has the only pure white phase. Accipiter is the largest genus in the family, having about fifty species. It is present worldwide, but is especially rich in Papua-New Guinea, where a small island like New Britain may have three to five endemic species or distinct sub-species.
Listen to the sound of Sparrowhawk
Copyright remark: Most sounds derived from xeno-canto
The nest is build in the fork of tree, often close to trunk where 2 or 3 branches start at same level. Also on horizontal branch, usually in lower parts of main canopy. Conifers are preferred where available. Selected tree usually close to path or clearing for convenient access. A new nest is built each year, sometimes on foundation of old nest of Woodpigeon or other species, though normally close to previous nests. The nest is a loose structure of twigs with deep cup. Nest size varies with position in tree, with nests in forks built up until surface area is large enough. Twigs up to 60 cm long are used, during laying, lined with fine twigs or bark chips. The clutch size is 4-6 (3-7) and the incubation lasts 33-35 days per egg, average 39-42 days for complete clutch. The young fledge after 24-30 days, males before females.
It does on occasions take small rodents and other small land based prey, but birds account for well over 90% and maybe as high as 98% of their diet.
copyright: Eddy Howland
Accipiter nisus is a widespread breeder across most of Europe, which accounts for
less than half of its global breeding range. Its European breeding population is large
(>340,000 pairs), and underwent a large increase between 1970-1990. Although there
were declines in a few countries during 1990-2000, populations were stable or
increasing across most of Europe-including the key one in Russia-and the species
increased slightly overall.
There are 32 000 breeding pairs in Britain with a further 11 000 in Ireland. Including non-breeders, by the end of summer the resident population will probably be around 170 000 birds.
150,000-170,000 breeding pairs widespread throughout most of Europe. The UK is a stronghold with about 34000 pairs. Russian population 140000-180000 Turkish population 3000-10000.
A Test Of The Condition-Bias Hypothesis Yields Different Results For Two Species Of Sparrowhawks (Accipizter)
on avian reproduction