Hi Penn,
Nice bit of behaviour.
Seemingly 'altruistic' activities exhibited by birds have been the source of
much inquiry since about the 1920s. Most investigations concentrate on
cooperative breeding, where a bird provides parental care to an animal that
is not its own genetic offspring. Much of this behaviour has been explained
by the observation that the helper is often closely related to the bird it's
helping to raise, thereby gaining genetic benefits, just as a real parent
does. In addition, unrelated helpers can often expect a higher probability
of future benefits, such as access to matings (not too unrelated) or
territorial resources.
So it seems true altruism is difficult to find (sigh), and most animals
considered engaging in such behaviour are thought to have been duped, like
many birds rearing obviously unrelated cuckoos. One great early photograph
(1920s?) shows a bird feeding a goldfish in a pond!
But who really knows what was behind the rosella's action? Flock activity
leads to safety in numbers - more eyes to spot a goshawk, etc. - and may
lead to tolerance of otherwise unacceptable behaviour, like pinching candy
from the beak of a baby. On the other hand, preening and cleanliness
can't be understated in the natural world, with birds apparently dropping
from trees due to parasite overload. Perhaps everyone's a winner.
Iain
From: Penn Gwynne <>
To: Birding Aus <>
Subject: [BIRDING-AUS] Yellow Tailed Black Cockatoo behavior
Date: Wed, 11 Dec 2002 18:33:18 -0800 (PST)
Dear Mark and Allan, and all very learned ladies and gents of this list,
could you help me please?
For some time now I have been lucky to have live near to my home a family
of Yellow Tailed Black Cockatoo, always a pleasure for me to see these
guys.
They excite my passion in birds and birding no end.
Lately they seem to have attracted a hanger on, so to speak. He's an
Eastern Rosella, that seems to enjoy living his life with them? early this
morning I noticed thee most unusual behavior between ER and what I think is
a young male YTBC from the same family as mentioned?
I may become wrong about the sex of the young YTBC.
But what I saw this am stunned me. With the entire family of YTBC's close
by, the ER decided to help out the young YTBC with his beak cleaning,
looked like young YTBC had been feeding on some local seeds with a good
covering over the outside of it's beak, probably caused by this fine scotch
mist rain we had this am.
Now is this opportunism? or has the ER performed this task for some time?
maybe taught by a parent? which is what I strongly suspect?
Or is this a case of I see my favorite food ... I'm brave, fearless .... I
can get that food from an astounded by my gall Mum and Dad YTBC? it knew it
could shock Mum and Dad YTBC? The drought must be hitting French Island eh?
Your thoughts would be most appreciated.
Yours Sincerely, John A. Gamblin ... one of the bird nuts they love to feed
on.
:^D>>>
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