Sunday, 22 August 2021

Urban birds at Hull. 25. Sparrowhawk

 

A small hawk, specialist bird hunter. Males much smaller than females, with dark grey upper parts and with rusty underparts, barred with brown. Iris is orange or red. Females are dark brown and creamy underneath, barred with grey with yellow iris. Immatures have more white on the head. Sparrowhawks can be notoriously difficult so see. Their advantage when hunting birds rely on not being seen, plus the element of surprise. Their wide wings and long tail allows them very high manoeuvrability in flight, able to twist and turn through branches in woods in short pursuit of prey, but also does take advantage of cover, it being hedgerows or roofs, to make a sudden appearance in a garden and take a bird who, seconds earlier, was feeding on a bird table. Early in the year, in sunny days, they soar over their territory, spreading the bright white feathers under their tails and occasionally engaging in display flights, in which they raise and then dive repeatedly. Female incubates and is fed by male. Often hungry female calling reveals the location of the nest, high up on a tree, on a fork by the trunk. Alarm calls of birds or sudden flushing of pigeons and Starlings can indicated the presence of a hunting Sparrowhawk. They are relentlessly mobbed by Carrion Crows. Males hunt small birds, while females can hunt larger prey, to the size of a Woodpigeon.

Adult female Sparrowhawk, Pearson Park, 25 March 2021. The Male sparrowhawk on the top shot is also at Pearson Park, 9th April 2021.

Status and distribution in Hull

A resident breeder widespread throughout Hull. Breeding in parks, cemeteries, plantations, railway sidings and gardens with mature trees, even in the city centre.

Carrion Crow mobbing Sparrowhawk, 11 Nov 2017.

Conservation and management

As the Peregrine, Sparrowhawk populations crashed through the 50s due to the lethal effects of organochlorine pesticides. Broughton states 'By the 1960s Sparrowhawks were so rare in Hull that one present in Northern Cemetery for two weeks in October 1963 was a very notable occasion'. Only one other record, probably a passage migrant is known in the Hull area in the whole decade! Populations started to recover in the 80s in the area and after a peak in the 90s, they appear to have undergone a decline in the last decade. It is hard to imagine how close to extinction they got in the UK. They are now an Amber listed species, and legally protected by The Wildlife and Countryside Act 1981.

26 March 2019, Sparrowhawk carrying nest building material, Pearson Park.

Adult immature female by the River Hull, 22 December 2020.

Adult male Sparrowhawk by the River Hull, 29 June 2021.

Recently fledged Sparrowhawk in the rain, Pickering Park, 23 July 2021.

Sparrowhawks soaring, Sculcoates, 14 August 2021.

More information

BTO Birdfacts, Sparrowhawk.

Broughton, R.K. 2002. Birds of the Hull Area. Kingston Press. Hull, UK.

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