This is the third in a sporadic series on bird bills that are even more remarkable than this wonderful organ normally is. The previous offering in this series can be found here.
Today you get two for the price of one. Although our two stars are entirely unrelated (indeed neither has any apparent close relatives) they have surprisingly similar bills.
The dramatic Shoebill Balaeniceps rex (ie 'king whale-head!') is a big bird indeed, standing up to 1.5 metres high and with a massive and unlikely-looking bill well over 20 centimetres long. It is a resident of the huge papyrus swamps of central east Africa, from Zambia north to Sudan. Due to the difficulty in penetrating these dense wet vastnesses it is not well known, and even its populations are uncertain. Like many other large birds it soars, and this is how it is often first seen, high over the reedbeds.
The bill is an all-purpose prey trap, though its emphasis is on large fish, especially lungfish and catfish. A range of other prey has been reported, and in some areas water snakes form a significant part of the diet. In addition to the hooked tip there are serrations along the edges, for further gripping and cutting efficiency. Adults will also carry loads of water in it for chicks in the ground-based nest for the first weeks of their life, until they can walk to water.
Half the world away, in another part of Gondwana, the Boat-billed Heron Cochlearius cochlearius is found throughout much of the tropical Americas, from Mexico south through central America and down to northern Argentina. Despite this large range it is not often seen - I've only seen it twice in nine trips to South America. It is currently placed in its own sub-family, but there are those who would reinstate an older view which believes that it warrants its own family, like the Shoebill.
It is only a third the size of the Shoebill, and so the similarly flattened and hooked bill is much smaller. It too snaps up a range of prey, especially fish and invertebrates and small land mammals. It also uses it as a scoop, in a way that no other heron does that I can think of.
More marvellous bills coming up sometime in the future; I hope you've enjoyed these as much as I did.
MEANTIME, BACK FRIDAY
2 comments:
A Shoebill featured in one of David Attenborough's recent series on Africa. The graphically presented fate of one of its chicks, and that of an elephant calf in the previous episode caused a good deal of discussion about how much viewers really need to see.
Yes, that series has just got to Australia too - sadly on one of the commercial channels, but by taping and skipping ads one can get a reasonably uninterrupted viewing. And his Galapagos series that you mentioned some time ago has also just started, this time blessedly back on the ABC.
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