Geoffrey
I am sceptical these birds have been
around before on any regular basis. My reasoning is that the probability of
sighting any bird is a function of:
- the
number of people searching and the efficacy of their search strategies;
- the
range of sites searched; and
- the
presence of birds to be found once searching commences.
I am not aware of parameters 1 and 2
changing in any significant way over the last 10 years (and I am certain that
the “Veerman Garden” site has been regularly searched!).
Ergo, the simplest explanation (Occam’s Razor,
etc) is that the birds were not here in any regular way before. Were we to believe
that they WERE there but missed we would need an (unnecessarily complex)
explanation of how everyone missed them as well as an explanation of how,
without changing sites and strategies, etc, we have now at last found them.
Of course, this argument reflects my
personal preference for theory over data, but we do HAVE (negative) data—that is,
the fact that they have not been reported despite thousands of trip reports….
Stephen
From:
Geoffrey Dabb [
Sent: Sunday, 15 July 2007 7:24 PM
To:
Subject: [canberrabirds]
Honeyeater Poll
The
following is a question on many people’s lips: are these 2 honeyeaters
breaking new ground or have they just been overlooked in the past?
I
am interested in what YOU (all chatline members) think, even if you haven’t
thought deeply about it.
‘Canberra area’ means the
ACT north of Tharwa.
Reply
to me with your view on the following statements:
B:
The Black-chinned Honeyeater has probably visited the Canberra area several
times over the last 10 years but has been overlooked
If
you agree, reply ‘B overlooked’, if you disagree reply ‘B not here’.
W:
The White-fronted Honeyeater has probably visited the Canberra area several times over the last 10
years but has been overlooked.
If
you agree, reply ‘W overlooked’, if you disagree reply ‘W not here’.
The
reason for your view is not the main thing, but if you want to add that, that
would be good. Add any qualifications or comments that you wish.
The
results of this poll, which is only about perceptions, will be reported in due
course.
