Saturday, March 3, 2012

Raptorama - Black-collared Hawk


Black-collared Hawk
Busarellus nigricollis
Accipitriforme Order – Accipitridae Family

Esp: Busardo Colorado
Ital: Poiana dal collare nero
Nd: Moerasbuizerd
Fr : Buse à tête blanche

Length: 46-51 cm
Wingspan: 114- 134 cm
Weight: M : 695 g – F : 795 g

Raptorama: Peter Jones takes a look at some of the raptor species encountered on various birding tours with both Worldwide Birding Tours and Spanish Nature. Why not join Peter on one of these wonderful tours and get a firsthand encounter with this great species of raptor? Further information on this tour  WBT

Distribution
Mexico, through Central America to South America, mainly in the north-eastern parts of the continent. It is absent on the west coast and southern Argentina. Normally sedentary in its range, but can move according to water levels.

Status.
Common in suitable habitat (see habitat below) in most parts of its wide range.
Some declines have occurred, largely due to drainage of wetlands i.e. in Panama. However, this species is not threatened at this moment and conservation status is of least concern.

Description
Black-collared Hawk has broad, rounded wings and short, squared tail. Adult has chestnut-cinnamon plumage overall with black shaft streaks on the back. Wings, the primary flight feathers are black. The tail is black with indistinct rufous bars.
Under parts displays clear black crescent on the upper breast. Head and neck are whitish to buffy-white, with fine brownish streaks on the crown. The hooked bill is black. Eyes are dark brown. Legs and feet are pale flesh to greyish-white. Both sexes are similar, with female larger than male. 
Immature is browner and darker than adults. Upperparts are spotted and barred rufous. Breast is paler, streaked darker. Belly is finely barred fuscous. Head is paler than body. 
Often soars with the wings slightly arched and the hands slightly raised. It is most frequently seen flying low over swampy areas. In level flight it has deep and powerful wing beats. It also glides with bowed wings and raised tips. The tail is usually closed.
Adults utter long guttural croaks, also short, hoarse, raspy “eh-rrrr”, and screaming whistles “hieeee”. This species is usually silent outside the breeding season. Juvenile utters long mewing calls from perch “wheeeeah”, and short cheeping.
There are two subspecies: B.n. nigricollis and B.n. leucocephalus. The later is larger and has a whiter head.

Habitat 
Frequents tropical zones with fresh or brackish water. It can be seen along large rivers, as well in open areas as in dense moist forest, swamps, lakes with floating vegetation and swampy lagoons. It occurs at up to 500 metres of elevation in Colombia.



Prey and feeding behaviour.
Feeds mainly on fish, caught by snatching fish from the water’s surface snagging fish with its talons. It hunts from low perch near water. When the prey is detected, it swoops down and catches the fish with its talons. This hawk has very specialised and unique feet, covered with quills, making it easier to capture and hold slippery fish. Snails and aquatic insects also form a part of its diet with lizards and rodents occasionally taken.



Breeding behaviour.
Breeding season varies according to range. Builds a nest in tall trees or in mangroves. The nest is a bulky platform made with sticks, later lined with green leafs. It is usually situated near water, at about 12-15 metres above the ground. Lays one single greyish-white egg spotted brown and darker grey. The nesting behaviour of this species is poorly known.


Raptorama tour brief. See HERE for full tour details and options.
The Pantanal is one of the largest wetlands in the world, encompassing approximately 210.000 km² spread over Brazil, Paraguay and Bolivia. During the rainy season from the end of October through March this area floods and plant life explodes. Then in April as the waters recede, the birds return in vast numbers and variety. Due to the wide-open areas between patches of forest, birds can be easily seen.
There are around 600 species of birds, 95 of mammals, and 50 of reptiles within this ecosystem. In the early morning and evening visitors can enjoy the magnificent spectacle of thousands of birds flying. The Jabiru (Jabiru mycteria) is commonly seen here and has become the animal symbol of the Pantanal. Macaws abound within this area. This is one of the last places where the largest hook bill, the endangered Hyacinth Macaw (Anodorhynchus hyacinthinus) can be seen daily.
Tour Options: We offer the possibility to extend this trip with a visit to the remaining parts of the Atlantic Forest, visiting the part close to the ever expanding city of Rio de Janeiro.


2 comments:

Mary Howell Cromer said...

Hi Peter, what a beautifully coloured bird. You got so many wonderful images, love the in flight image of it yelling as it came in your direction! Very wonderful, vibrant looking images.
You may interested in my newest blog entry too...it was a very special encounter~

Peter Jones said...

Thanks Mary, these hawks are colourful and always delightful to see. They are common in local areas around the Pantanal Brazil, so quite a few photo opportunities there. I am hoping to get across to Brazil again this October. Off to Morocco and the Sahara later this month and again in April, so no doubt have a few stories for the blog! Thanks again Mary. Peter