Fjällvråk vs ormvråk

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Dietary biology
The common buzzard is a generalist predator which hunts a wide variety of prey given the opportunity. Varierar kraftigt i teckningen från väldigt ljusa, till nästan helmörka individer.

Förväxlingsrisk:
Bivråk: Har ljusare, grått huvud och klenare näbb.
Fjällvråk: Ryttlar oftare än övriga vråkar.

While less individually variable in Europe, the honey buzzard is more extensive polymorphic on underparts than even the common buzzard. Vråkparet försvarar sitt revir aggressivt mot andra rovfåglar under häckningsperioden.

Ett kulturellt djur – både beundrat och förföljt

Ormvråken har länge varit en del av folktron och betraktades förr som en olycksbringare om den syntes kretsa över ett hus.

The flight feathers on perched European buzzards are always brown in the nominate subspecies (B. The latter buzzard has a streaky rufous head and is white below with a contrasting bold dark chest in adult plumage and, in juvenile plumage, has heavy, dark blotches on the chest and flanks with pale wing-linings.

More or less any snake in Europe is potential prey and the buzzard has been known to be uncharacteristically bold in going after and overpowering large snakes such as rat snakes, ranging up to nearly 1.5 m in length, and healthy, large vipers despite the danger of being struck by such prey.

Particularly in migration, as was recorded in the case of steppe buzzards' movement over Israel, buzzards readily adjust their direction, tail and wing placement and flying height to adjust for the surrounding environment and wind conditions. During the mutual displays, the male may engage in exaggerated deep flapping or zig-zag tumbling, apparently in response to the female being too distant.

In eastern Europe and much of the Asian range of common buzzards, the long-legged buzzard (Buteo rufinus) may live alongside the common species. Vissa individer är nästan helt vita, andra nästan svarta – men vanligast är en brun kropp med ljusare ”v”-teckning på bröstet. Ibland gör hannen lekfulla anfall mot honan, som därvid kan vända sig på rygg och avvärja skenattackerna med de uppåtsträckta klorna.

In the Ukraine, 30.8% of the food by number was found to be insects. In most dietary studies, invertebrates are at best a minor supplemental contributor to the buzzard's diet.

Breeding
Nesting territories and density
Home ranges of common buzzards are generally 0.5 to 2 km2. A study from Great Britain indicated that hovering does not seem to increase hunting success.

However, displays are not uncommon throughout year in resident pairs, especially by males, and can elicit similar displays by neighbors. Still-borns of deer are also visited with some frequency.

Den är särskilt vanlig i jordbrukslandskap med inslag av skogsdungar, men kan även ses vid myrar, hyggen och fjällnära barrskog. In the Teno massif of the Canary Islands, the average density was estimated as 23 pairs per 100 km2, similar to that of a middling continental population.

Birds were the primary food for common buzzards in the Italian Alps, where they made up 46% of the diet against mammal which accounted for 29% in 146 prey items.