[3][6] The first formal description of the common buzzard was by the Swedish naturalist Carl Linnaeus in 1758 in the tenth edition of his Systema Naturae under the binomial name Falco buteo.
The western buteo group is mainly resident or short-distance migrants and includes: The eastern vulpinus group includes: At one time, races of the common buzzard were thought to range as far in Asia as a breeding bird well into the Himalayas and as far east as northeastern China, Russia to the Sea of Okhotsk, and all the islands of the Kurile Islands and of Japan, despite both the Himalayan and eastern birds showing a natural gap in distribution from the next nearest breeding common buzzard.
Juvenile buzzards are quite similar to adult in the nominate race, being best told apart by having a paler eye, a narrower subterminal band on the tail and underside markings that appear as streaks rather than bars.
Flight feathers of typical European buzzards are largely greyish, the aforementioned dark wing linings at front with contrasting paler band along the median coverts.
Juvenile nominate buzzards are best told apart from adults in flight by the lack of a distinct subterminal band (instead showing fairly even barring throughout) and below by having less sharp and brownish rather than blackish trailing wing edge.
Extreme pale birds are largely whitish with variable widely spaced streaks or arrowheads of light brown about the mid-chest and flanks and may or may not show dark feather-centres on the head, wing-coverts and sometimes all but part of mantle.
Compared to the nominate race, rufous vulpinus show a patterning not dissimilar but generally far more rufous-toned on head, the fringes to mantle wing coverts and, especially, on the tail and the underside.
Adult forest buzzards compared to the typical adult steppe buzzard (rufous morph) are also similar, but the forest typically has a whiter underside, sometimes mostly plain white, usually with heavy blotches or drop-shaped marks on abdomen, with barring on thighs, more narrow tear-shaped on chest and more spotted on leading edges of underwing, usually lacking marking on the white U across chest (which is otherwise similar but usually broader than that of vulpinus).
[1][49][50] The common buzzard generally inhabits the interface of woodlands and open grounds; most typically the species lives in forest edge, small woods or shelterbelts with adjacent grassland, arables or other farmland.
Although adaptable to and sometimes seen in wetlands and in coastal areas, buzzards are often considered more of an upland species and neither appear to be regularly attracted to or to strongly avoid bodies of waters in non-migratory times.
[65] In Israel, migrant buzzards rarely soar all that high (maximum 1,000–2,000 m (3,300–6,600 ft) above ground) due to the lack of mountain ridges that in other areas typically produce flyways; however tail-winds are significant and allow birds to cover a mean of 9.8 metres per second (22 miles per hour).
In northern Germany, buzzards were recorded to show preferences in fall for areas fairly distant from nesting site, with a large quantity of vole-holes and more widely dispersed perches.
[4][17] Migrating steppe buzzards will rise up with the morning thermals and can cover an average of hundreds of miles a day using the available currents along mountain ridges and other topographic features.
Distances covered by migrating steppe buzzards in one way flights from northern Europe (i.e. Finland or Sweden) to southern Africa have ranged over 13,000 km (8,100 mi) within a season .
[104][105][106][107] Rodent prey taken have ranged in size from the 7.8 g (0.28 oz) Eurasian harvest mouse (Micromys minutus) to the non-native, 1,100 g (2.4 lb) muskrat (Ondatra zibethicus).
[108] Other rodents taken either seldom or in areas where the food habits of buzzards are spottily known include flying squirrels, marmots (presumably very young if taken alive), chipmunks, spiny rats, hamsters, mole-rats, gerbils, jirds and jerboas and occasionally hearty numbers of dormice, although these are nocturnal.
However, it has been indicated that the main prey remains consist of rodents such as the four-striped grass mouse (Rhabdomys pumilio) and Cape mole-rats (Georychus capensis).
One of these main prey types of import in the diets of common buzzards are leporids or lagomorphs, especially the European rabbit (Oryctolagus cuniculus) where it is found in numbers in a wild or feral state.
Moles are taken particularly often among this order, since as is the case with "vole-holes", buzzards probably tend to watch molehills in fields for activity and dive quickly from their perch when one of the subterranean mammals pops up.
[99][115] In Bari, Italy, the Roman mole (Talpa romana), of similar size to the European species, was the leading identified mammalian prey, making up 10.7% of the diet.
[94][98][100][96][124][125] Numerous larger mammals, including medium-sized carnivores such as dogs, cats and foxes and various ungulates, are sometimes eaten as carrion by buzzards, mainly during lean winter months.
[87][118][135] In Bari, Italy, reptiles were the main prey, making up almost exactly half of the biomass, led by the large green whip snake (Hierophis viridiflavus), at 24.2% of food mass.
[166] Despite often being dominated in nesting site confrontations by even similarly sized raptors, buzzards appear to be bolder in direct competition over food with other raptors outside of the context of breeding, and has even been known to displace larger birds of prey such as red kites (Milvus milvus) and female buzzards may also dominate male goshawks (which are much smaller than the female goshawk) at disputed kills.
Various other aerial displays include low contour flight or weaving among trees, frequently with deep beats and exaggerated upstrokes which show underwing pattern to rivals perched below.
[3][204] Talon grappling and occasionally cartwheeling downward with feet interlocked has been recorded in buzzards and, as in many raptors, is likely the physical culmination of the aggressive territorial display, especially between males.
[216] High breeding success was detected in Argyll, Scotland, due likely to hearty prey populations (rabbits) but also probably a lower local rate of persecution than elsewhere in the British isles.
Breeding success was lower farther from significant stands of trees in the Midlands and most nesting failures that could be determined occurred in the incubation stage, possibly in correlation with predation of eggs by corvids.
[3][6] Between 44,000 and 61,000 pairs nested in Great Britain by 2001 with numbers gradually increasing after past persecution, habitat alteration and prey reductions, making it by far the most abundant diurnal raptor there.
However, the rate of increase was significantly greater in males than in females, in part because of reintroduced Eurasian eagle-owls to the region preying on nests (including the brooding mother), which may in turn put undue pressure on the local buzzard population.
[225] Given its relative abundance, the common buzzard is held as an ideal bioindicator, as they are effected by a range of pesticide and metal contamination through pollution like other raptors but are largely resilient to these at the population levels.