Re: Harmonious depredations

[Ronald Orenstein <ornstn@home.com>]

> Martin's observation is remarkable; but it is remarkable because it is so
> rare.  In my fifty years of existence, I have never seen geese-size birds
> nesting in a visible suburban location.

Come to Toronto sometime.  Or try Boulders Beach near Cape Town, where 
Jackass Penguins nest successfully on the edge of a parking lot despite 
predation by genets and mongooses.

> What about Ron's claim that ostriches nest in harmony with predators?

I made no such claim.  I said that they coexist with predators, who 
certainly take eggs (their nesting success rate is only about 10%), without 
being exterminated by them - a very different point and one directly 
contradicting John's hypothesis.

My statement about ostrich nesting is not merely the report of an anecdote 
(though you might like to look at the photo of an ostrich nest on open sand 
in the middle of the Namib Desert on p. 81 of Vol. 1 of the highly 
authoritative Handbook of the Birds of the World, with the caption "...the 
large white eggs are highly conspicuous, and when left unattended may 
provide a welcome meal for scavengers like hyenas and jackals."  Ostrich 
nests are placed, according to HBW, "at sites with good visibility roughly 
in the middle of the territory".

Though rheas frequently hide their nests, "the male sometimes uproots all 
the vegetation within a radius of 2-3 meters around the nest, apparently to 
isolate it, in case there is a fire".  Emu nests are "always in a fairly 
open site, where the sitting male has a good view of the surrounding land".

--
Ronald I. Orenstein                           Phone: (905) 820-7886
International Wildlife Coalition              Fax/Modem: (905) 569-0116
1825 Shady Creek Court
Mississauga, Ontario, Canada L5L 3W2          mailto:ornstn@home.com