Crested Goshawk / Burung Lang Sikap

With short broad wings and a longish tail, the goshawk is a bird suited for manoeuvrability through thick foliageNow, however, it is increasingly common in cities.  Ecologists had believed that human activity, buildings, traffic and especially the highly fragmented nature of urban forest would prevent these hawks from thriving in the city.  What was left out of the analysis was the one offsetting positive factor of city life- an abundant food supply.  Cities around the world have a superabundance of sparrows, doves and squirrels as compared to the countryside.  Moreover, seasonal variation is less in the city; food is plentiful all year long.  This allows for an earlier nesting season and with it the possibility of re-nesting if the first clutch fails.

Staring at the camera; Taman Tasik Menjalara


Consequently some birds of prey have adapted to city life.  Researchers have found that sub-adult birds are more likely to gain a territory in the city than in the countryside- where all good territories are likely held by long-lived mated pairs.  Age is determined from plumage.  Crested goshawks acquire adult plumage three years after hatching.  Younger birds are brownish on the back with dark brown belly stripes.

Birds of prey that are successfully moving into the city include peregrine falcons (in European cities), cooper’s hawks (in American cities), black sparrowhawks (in Cape Town) and crested goshawks (here and Southeast Asia generally).

Crested goshawks are 30–46 cm in length.  As is the case with many birds of prey, the female is about 30 percent larger than the male.  This size differential likely reduces competition for food resources.  The smaller males will tend to hunt sparrows and the larger female will concentrate her efforts on pigeons and doves.

The crest is usually held low, look carefully.  

Taman Alam, Kuala Selangor




video: https://youtu.be/TVEn4pMSiRg (An urban bird)

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