Common Buzzard

Common Buzzard
In Scotland
Conservation status
Least Concern (IUCN 3.1)[1]
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Order:	Accipitriformes
Family:	Accipitridae
Genus:	Buteo
Species:	B. buteo
Binomial name
Buteo buteo (Linnaeus, 1758)
Subspecies
7-10, see text
Dark green: All-year distribution Light green/blue: Breeding/winter range of Steppe Buzzard.

The Common Buzzard (Buteo buteo) is a medium to large bird of prey, whose range covers most of Europe and extends into Asia. It is usually resident all year, except in the coldest parts of its range, and in the case of one subspecies.

Description

The Common Buzzard measures between 40 and 58 cm (16 and 23 in) in length with a 109–136 cm (43–54 in) wingspan and a body mass of 427–1,364 g (0.94–3.01 lb), making it a medium-sized raptor.^[2][3]

This broad-winged raptor has a wide variety of plumages, and in Europe can be confused with the similar Rough-legged Buzzard (Buteo lagopus) and the only distantly related Honey Buzzard (Pernis apivorus), which mimics the Common Buzzard's plumage for a degree of protection from Northern Goshawks^{[citation needed]}. The plumage can vary in Britain from almost pure white to black, but is usually shades of brown, with a pale 'necklace' of feathers.

Systematics

At Hamerton Zoo, England

The Common Buzzard was first described by Linnaeus in his Systema naturae in 1758 as Falco buteo.^[4] Buzzard subspecies fall into two groups. The western Buteo group is mainly resident or short-distance migrants. They are:

• Buteo buteo buteo: most of Europe
• B. b. rothschildi: Azores
• B. b. insularum: Canary Islands
• B. b. arrigonii: Corsica and Sardinia
• B. b. menetriesi: Caucasus
• B. b. harterti: Madeira, doubtfully distinct from nominate Buteo

The eastern vulpinus group includes

• B. b. vulpinus (Steppe Buzzard): Eurasia: migrant breeder
• B. b. burmanicus (Himalayan Buzzard): Himalayas and western China
• B. b. japonicus: Japan: resident
• B. b. toyoshimai: Izu Islands and Bonin Islands
• B. b. oshiroi: Daito Islands

Two resident forms on islands close to Africa are often assigned to the first group, but appear to be distinct species, more closely related to the African Long-legged Buzzard, based on biogeography and preliminary mtDNA cytochrome b sequence data (Clouet & Wink 2000):

• Buteo bannermani (Cape Verde Buzzard): Cape Verde Islands
• Buteo socotraensis (Socotra Buzzard) of Socotra

Behaviour

In flight, Devon, England. There are around 40,000 breeding pairs in the United Kingdom

The Common Buzzard breeds in woodlands, usually on the fringes, but favours hunting over open land. It eats mainly small mammals, and will come to carrion. A great opportunist, it adapts well to a varied diet of pheasant, rabbit, other small mammals to medium mammals, snakes and lizards, and can often be seen walking over recently ploughed fields looking for worms and insects. The birds have incredible strength and are therefore able to pick up food of all weights.^{[citation needed]}

Buzzards do not normally form flocks, but several may be seen together on migration or in good habitat. The Victorian writer on Dartmoor, William Crossing, noted he had on occasions seen flocks of 15 or more at some places. Though a rare occurrence, as many as 20 buzzards can be spotted in one field area, approximately 30 metres apart, so cannot be classed as a flock in the general sense, consisting of birds without a mate or territory. They are fiercely territorial, and, though rare, fights do break out if one strays onto another pair's territory, but dominant displays of aggression will normally see off the interloper. Pairs mate for life. To attract a mate (or impress his existing mate) the male performs a ritual aerial display before the beginning of spring. This spectacular display is known as 'the roller coaster'. He will rise high up in the sky, to turn and plummet downward, in a spiral, twisting and turning as he comes down. He then rises immediately upward to repeat the exercise.

The call is a plaintive peea-ay, similar to a cat's meow.

Steppe Buzzard

The Steppe Buzzard, B. (b.) vulpinus breeds from east Europe eastward to the Far East, excluding Japan. It is a long-distance migrant, excepting some north Himalayan birds, and winters in Africa, India and southeastern Asia. In the open country favoured on the wintering grounds, steppe buzzards are often seen perched on roadside telephone poles.

Steppe Buzzard is some times split as a separate species, B. vulpinus. Compared to the nominate form, it is slightly smaller (45–50 cm long), longer winged and longer tailed. There are two colour morphs: the rufous form which gives this subspecies its scientific name (vulpes is Latin for "fox"), and a dark grey form.

The tail of vulpinus is paler than the nominate form, and often quite rufous, recalling North American Red-tailed Hawk. The upper wings have pale primary patches, and the primary flight feathers are also paler when viewed from below. Adults have a black trailing edge to the wings, and both morphs often have plain underparts, lacking the breast band frequently seen in B. b. buteo.

Forest Buzzard

The Forest Buzzard, B. (b.) trizonatus,^{[citation needed]} is another form sometimes upgraded to a full species, though most recent authorities have placed it as a subspecies of another species, the Mountain Buzzard, B. oreophilus. This is a resident breeding species in woodlands in southern and eastern South Africa.

It is very similar to the abundant summer migrant Steppe Buzzard, but the adult can be distinguished with a good view by its whiter underparts and unbarred flanks. The juvenile differs from the same-age steppe buzzard by its white front and tear-shaped flank streaks.

The Forest Buzzard, as its name implies, inhabits evergreen woodlands, including introduced eucalyptus and pines, whereas the steppe buzzard prefers more open habitats. However, habitat alone is not a good indicator for these forms.

References

1. ^ BirdLife International (2010). "Buteo buteo". IUCN Red List of Threatened Species. Version 2011.1. International Union for Conservation of Nature. http://www.iucnredlist.org/apps/redlist/details/181383. Retrieved 14 July 2011. 
2. ^ CRC Handbook of Avian Body Masses by John B. Dunning Jr. (Editor). CRC Press (1992), ISBN 978-0849342585.
3. ^ Raptors of the World by Ferguson-Lees, Christie, Franklin, Mead & Burton. Houghton Mifflin (2001), ISBN 0-618-12762-3.
4. ^ (Latin) Linnaeus, C (1758). Systema naturae per regna tria naturae, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. Tomus I. Editio decima, reformata.. Holmiae. (Laurentii Salvii).. pp. 90. "F. cera pedibusque luteis, corpore fusco, abdomine paludo maculis fuscis." 

• Clouet, Michel and Wink, Michael (2000): The Buzzards of Cape Verde (Buteo (buteo) bannermani) and Socotra (Buteo buteo spp.) - First results of a genetic analysis based on nucleotide sequences of the cytochrome b gene. Alauda 68(1): 55-58. PDF fulltext
• Ferguson-Lees, Christie, Franklin, Mead and Burton Raptors of the World ISBN 0713680261
• Mullarney, Svensson, Zetterstrom and Grant, Collins Bird Guide ISBN 0-00-219728-6
• Ian Sinclair, Phil Hockey and Warwick Tarboton, SASOL Birds of Southern Africa (Struik 2002) ISBN 1-86872-721-1

External links

• Madeira Birds: Buzzard. Page about the controversial subspecies harterti. Retrieved 2006-NOV-28.
• Ageing and sexing (PDF) by Javier Blasco-Zumeta