Thứ Ba, 13 tháng 3, 2012

Great crested grebe

Podiceps cristatus

Photo by Ken Billington (Wikipedia)

Common name:
great crested grebe (en); mergulhão-de-crista (pt); grèbe huppé (fr)somormujo lavanco (es); haubentaucher (de)


Taxonomy:
Order Podicipediformes
Family Podicipedidae


Range:
This species is found across most of Europe and central Asia, wintering also in southern Asia. There are some scattered colonies in Africa, from Tunisia and Egypt in the north, through a few colonies in central Africa and into South Africa. There are also nesting colonies in southern Australia and New Zealand, with individuals wintering in eastern and northern Australia.


Size:
These birds are 46-51 cm long and have a wingspan of 59-73 cm. They weigh 0,8-1,4 kg.


Habitat:
Great crested grebes are mostly found on fresh or brackish waters with abundant emergent and submerged vegetation, showing a preference for non-acidic eutrophic waterbodies with flat or sloping banks and muddy or sandy substrates, and with large areas of open water. They are can also be found in swamps, saltpans, estuaries and reservoirs.



Diet:
They eat fishes, aquatic insects, amphibians, crustaceans, spiders and seeds.


Breeding:
The breeding season of the great crested grebe varies between different parts of its range, occurring in April-September in Europe and Asia, all year round in Africa and in November-March in Australia. The nest is a platform of aquatic plant matter either floating on water and anchored to emergent vegetation or built from the lake bottom in shallow water. The female lays 3-4 eggs which are incubated by both parents for 27-29 days. The chicks leave the nest soon after hatching and are often carried around on the backs of their parents, fledging 71-79 days after hatching.


Conservation:
IUCN status - LC (Least concern)
This species has an extremely large breeding range and the global population is estimated at 920.000-1.400.000 individuals. The overall population trend is uncertain, as some populations are decreasing, while others are increasing or have unknown trends.

Không có nhận xét nào:

Đăng nhận xét