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. Princeton University Press. Tyack, A. J., Walls, S. S., & Kenward, R. E. (1998). Inexperienced and over-enthusiastic observers have even mistaken darker birds for the far larger and differently proportioned golden eagle (Aquila chrysaetos) and also dark birds for western marsh harrier (Circus aeruginosus) which also flies in a dihedral but is obviously relatively much longer and slenderer winged and tailed and with far different flying methods.  The amount of fledgling and younger birds preyed upon relative to adults is variable, however.  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 (4 ft 11 in) in length, and healthy, large vipers despite the danger of being struck by such prey. However, size is not diagnostic unless side by side as the two buzzards overlap in this regard. (2012). The sexes are colored similarly, but females are substantially larger than males. A. Steppe buzzards tend to appear smaller and more agile in flight than nominate whose wing beats can look slower and clumsier. The common buzzard is a generalist predator which hunts a wide variety of prey given the opportunity. The nest is flat and bulky made from sticks, twigs and small branches and lined with green leaves.  In nestlings, the first down replaces by longer, coarser down at about 7 days of age with the first proper feathers appearing at 12 to 15 days. (1951).  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. Redpath, S. M., Clarke, R., Madders, M., & Thirgood, S. J. The underside can be uniformly pale to dark rufous, barred heavily or lightly with rufous or with dusky barring, usually with darker individuals showing the U as in nominate but with a rufous hue.  All four ground squirrels that range (mostly) into eastern Europe are also known to be common buzzard prey but little quantitative analysis has gone into how significant such predator-prey relations are. Schreiber, A., Stubbe, A., & Stubbe, M. (2001). Due to their large numbers in edge habitats, common buzzards frequently feature heavily in the eagle-owl's diet. In autumn, numbers of steppe buzzards recorded in migration have ranged up to 32,000 (recorded 1971) in northwestern Turkey (Bosporus) and in northeastern Turkey (Black Sea) up to 205,000 (recorded 1976). 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.  In southern Spain, birds were equal in number to mammals in the diet, both at 38.3%, but most remains were classified as "unidentified medium-sized birds", although the most often identified species of those that apparently could be determined were Eurasian jays and red-legged partridges (Alectoris rufa). Nearly every study from the continent makes reference to the importance, in particular, of the two most numerous and widely distributed European voles: the 28.5 g (1.01 oz) common vole (Microtus arvalis) and the somewhat more northerly ranging 40 g (1.4 oz) field vole (Microtus agrestis).  The onset of migratory movement for steppe buzzards back to the breeding grounds in southern Africa is mainly in March, peaking in the second week.  Females average about 2–7% larger than males linearly and weigh about 15% more.  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. , Other rodents are taken largely opportunistically rather than by preference.  The common buzzard generally lacks the propensity of its Nearctic counterpart, the red-tailed hawk, to occasionally nest on or near manmade structures (often in heavily urbanized areas) but in Spain some pairs recorded nesting along the perimeter of abandoned buildings.  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.  Common buzzards may hunt nearly 80 species passerines and nearly all available gamebirds.  Common buzzard subspecies fall into two groups. In Murcia, the most numerous prey was the 77.2 g (2.72 oz) ocellated lizard (Timon lepidus), at 32.9%. Frölich, K., Prusas, C., Schettler, E., & Hafez, H. M. (2002).  In Seversky Donets, Ukraine, birds and mammals both made up 39.3% of the foods of buzzards.  In Poland, buzzards productivity was correlated to prey population variations, particularly voles which could vary from 10–80 per hectare, whereas goshawks were seemingly unaffected by prey variations; buzzards were found here to number 1.73 pair per 10 km2 (3.9 sq mi) against goshawk 1.63 pair per 10 km2 (3.9 sq mi).