Sorry I left out a word: Ecology is the study of why how many of what
species live where.
Also worth mentioning, John asked a question about one species. In asking,
there is an expectation that an answer could be known. There are a
restricted number of species that are sufficiently well studied to allow us
to know many or most of the relevant answers.
The vast number of species have not been studied to anything like the
required extent, we can have enough general knowledge to be able to suggest
some sensible guesses. I reckon Cicadabird and indeed most uncommon birds
would be in that group. Maybe ACT forests aren't as caterpillar-ridden as
coastal forests but that would take a huge amount of work to find out, and
even then, it would take much more work to find out if that is the reason
that impacts on the answer to the question about the Cicadabird.
Most existing species we wouldn't even be close to begin to guess at any
detail of their ecology. This includes species not even known.
Philip
-----Original Message-----
From: Philip Veerman
Sent: Thursday, 1 December 2011 2:34 PM
To: 'John Leonard'; 'Canberra Birds'
Subject: Cicadabird rarity
Hello John,
That is a big question. Ecology is the study of how many of what species
live where. I think that every species would have 100 different answers to
that type of question. Migration is a big thing for any animal to do and the
benefits need to outweigh the big costs and risks. Cicadabirds are normally
a forest bird. BFCS are not. We don't have much forest. More to the point,
there is plenty of unsuitable land between the ACT and their normal range.
That provides a significant barrier. Why should they bother to come here? It
is not as if they are abundant anywhere and need to spread out to get away
from others of their species..... I know some do come here. I have seen them
in the Brindabella range.
Philip
-----Original Message-----
From: John Leonard
Sent: Thursday, 1 December 2011 9:37 AM
To: Canberra Birds
Subject: Cicadbird rarity
Thinking about my long-standing ACT bogey bird, the Cicadbird. Why are they
so rare?
In SE Qld they live in rainforest and whilst not common, you see them
regularly. On the NSW coast I've seen them a few times in schelrophyll. But
they seem very few and far between the ACT.
They don't need hollows for nesting and they eat caterpillars, so why aren't
they as common as BFCS are in woodland?
Is it that ACT forests aren't as caterpillar-ridden as coastal forests?
--
John Leonard
*
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