Tuesday, April 22, 2008

Exemplary Birds

By far the largest of our 3 local bustard species, the Kori bustard, is known as the heaviest and tallest bird capable of sustained flight. Other than its huge size (1,35m), the Kori bustard can also be identified by its crested head. This bird tends to walk slowly with measured strides, and although reluctant to fly, it at least can! - I mean this in comparison to the ostrich (at up to 2m, the biggest bird in the world - but: it can't fly). I recently photographed this magnificent and usually solitary Kori bustard at Etosha (Namibia).

The largest of the African storks is the Saddlebill stork (right). It's often found near water (as this one in the Kruger National Park), because its main diet consists of crabs, shrimps, frogs and fish - although it also feeds on small mammals and even birds. Because the Saddlebill stork is listed as endangered, I get very excited when I have the chance to encounter this colourful bird.

The bird I think of as the most regal-looking amongst the South African birds, is the Martial eagle - known as a fierce bird of prey. It also is one of the largest of our "true" eagles, with a wingspan of 2,1m or more.

Trivia: "true" eagles have fully feathered legs, distinguishing them from e.g. snake eagles and (all) other raptors.

Yes, I know it's not the first time that I present a Ground hornbill on this blog, but because of its size, I think this bird deserves another mention today. It's the largest of the hornbill family and grows to a length of up to 1,1m. I must admit, I hate it when some people describe this bird's appearance as a cross between a domestic turkey and a crow, because I don't like it when wild animals/birds are compared with domestic animals. Despite its size (and name), this bird roosts in trees - as the one in the photo, sitting on a branch - but forages on the ground. Although also listed as endangered, when one does encounter ground hornbills in the wild, they aren't solitary birds but instead are found in groups of 4-10 individuals. Their natural habitat is bushveld, woodland or montane grassland.

Generally, hornbills are fairly large birds, although half the size of their "cousin", the Ground hornbill. All hornbills (and as their name suggests) are easily identifiable by their enormous, mostly curved bills. In most cases, the upper mandible of male hornbills is "topped" by a growth called a "casque", as is visible on this photo of a Grey hornbill. This member of the hornbill family keeps to trees (= mainly "arboreal" > on the ground) in which it forages for food.

In my eyes, the most "comical"-looking (or even fierce/not amused?) in this family of birds, is the Yellowbilled hornbill. The casque of this member "adorns" the entire length of the male's upper mandible, which adds thickness to its bill. This hornbill feeds both on the ground and in fruiting trees, and is often seen at various, national park campsites across the parts of our country, which represents this bird's habitat.

The Redbilled hornbill is a look-alike of the previous species, but somewhat smaller in size. It's mostly by the colour of their bills that one can distinguish between the two family members, and the Redbilled hornbill also doesn't have a casque on its red bill. This bird mostly forages on open ground or in dung, and is often seen actively digging with its bill.

Some people, e.g. overseas visitors, like to compare our hornbills with toucans - found in tropical America - but the 2 bird species are in no way related!

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