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Re: Dumb Animals ? (especially Kakapos)
>Let me start by saying that I don't believe in anthropomorphising animals
>(except when there's a funny point to be made), and that I feel quite
>strongly that animals are very well suited for what they do. Disclaimer
>aside, let's talk about Kakapos. All my information comes from detailed
>reading of that classic zoological literature "Last Chance to See" by the
>esteemed zoologist Douglas Adams and well-known Science fiction author
>Mark Carwardine (sp?), as well as a short time at the University of
>Otago, Dunedin, NZ
A great book but not exactly the last word in zoology. It's a bit out of
date but those interested might want to look at a popular book called
"Kakapo Country" by David Cemmick and Dick Veitch (Hodder and Stoughton 1987).
. Kakapos are large flightless ground parrots which
>have not survived the introduction of just about every destructive mammal
>in creation into New Zealand - there's about 30 or 40 left.
In fact all wild kakapos have now been captured and relocated to offshore
islets from the last surviving population on Stewart Island; the bird is
therefore extinct in its original range.
>mostly because of the animals inability to cope with the presence of
>small viscious mammals like rats, cats and humans, but I also believe the
>bird itself has to take some of he blame.
Actually there are very few viscous mammals, but a number of vicious ones;
of course the kakapo is an island isolate, and can hardly be "blamed" for
failing to cope with a situation that is not the one it evolved to handle.
The Kakapo male spends quite a
>long time constructing a nest and trail leading up to it. Then he calls
>to the female. His call is an almost subsonic booming, which carries for
>miles and supposedly is more felt than heard. Problem is, the thing about
>subsonics is that whilst they are transmitted over a long range, it is
>not easy to locate where the sound. Therefore the female can hear him,
>but she'll be buggered if she can find him.
If this were literally true the bird could not have evolved at all. In fact
the kakapo has a highhly-evolved, vaguely grouse-like lek system. The male
does not build a "nest" (in fact he takes no part in nest care) but a
"booming bowl", a depression in the earth, often backed by a natural sound
reflector such as a stone or tree trunk. Several males construct these
bowls in a specific area, with each male about 50 metres from the others -
thereby localizing the female's search area, even assuming that she really
has the same trouble locating the sound that we humans do. Each male may
boom as many as 17,000 times per night; the booms areaudible up to 7 km.
away. The male also constructs a series of tracks (not just one) leading to
the bowl; the tracks presumably assist the female in homing in on the male.
Rather than being non-adaptive, Cemmick and Veitch describe the system as
"ideal for such a large and long-lived bird" were it not for human induced
changes to its environment.
Ronald I. Orenstein Phone: (905) 820-7886 (home)
International Wildlife Coalition Fax/Modem: (905) 569-0116 (home)
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