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Hi Chris,
Fair question. I guess it depends on the meaning
applied to the word "should". As in, does it have tones of morality? Not
really. In my use it suggests my estimate of likelihood. It comes
from a point I raised in my GBS report so it relates to trends since 1981. Back
in 1981 there was only one good generally available field guide that included
raptors. That was Slater's volume 1. Even so, many people then would only have
had Cayley's "What bird is that" (because for decades that was the bird book of
choice). So the information to help observers wasn't so available. Now there are
several good books. I think that having more than one reference helps in
identifying a bird, if it is not one that the observer knows well. The range and
choice of books has increased progressively over the years. Also I suggest most
COGites own at least two, which helps a lot. Whilst given a good view,
identification of Little Eagles from other similar sized brown raptors is
easy. On poor views it could be described as not easy and sometimes just not
possible. Also COG has run a couple raptor id workshops over that time. It might
help to copy here the earlier messages from Jerry Olsen and Stephen Debus
(author of one field guide to raptors book) as well as my earlier message on the
subject (that I had forgotten about yesterday, so repeated my self a bit -
sorry, it is not for the first time). I hope they don't mind, I wouldn't think
so.
I don't agree with Jerry's comment below that "we need a photo, video, or a repeated visit where
we see the bird again to say with certainty what it was." It is just my opinion and you can make your own, that Jerry was being
overly pessimistic in the abilities of people and I guess this attitude was
carried forward into his CBN article. Obviously I did not like that this
seemed to extend into a criticism of the GBS data (which just provided the
information), within a publication of COG's. I thought that the connection
between the two sets of data could have been better explored. Maybe Jerry is
(obviously not talking about himself) but dealing a lot with students, some of
which may have good academic levels but take on a bird project, never having had
any interest in or experience in bird observing and identification. For example,
I am reminded of Christine Cantor who did a project on W-w Choughs that I
produced for appearance in CBN in 1988. She did a quite good little study of the
family of birds on her family's property but I sat with her at the UC campus one
lunch time and explained to her that Magpie-larks were not young Magpies.
I am confident of my ability to identify these birds and
I am sure many other COGites are, too. I am also wise enough to realise that
there are some circumstances in which case the conditions were not good enough
to be sure of the id and that some remain as unidentified. I trust most COG
people to do the same. Maybe Jerry has a different perception of COG people than
I do.
Jerry Olsen's message:
Thanks
Phillip
The thing about certainty in identification of these raptors is
validation,
I mean, we need a photo, video, or a repeated visit where we see
the bird
again to say with certainty what it was. For example, I would not
have
published the plover paper in AFO 22: 1 2005 without photographs. It
would
be pointless. Stephen and I are currently discussing a series of
falcon
photos from Ashmore Reef, a discussion we could not have without
photos or a
body. We can¹t validate sightings by saying people should know
what they
look like, people often report back descriptions from
books.
Secondly, I looked hardest for Little Eagles in the 2005 season,
and found
ACT Whistling Kites and ACT Little Eagles in about the same
numbers, but
found two successful ACT Whistling kite nests, and no successful
Little
Eagle nests. The even numbers off Whistling Kites and Little Eagles
should
show up in your 2005 data.
Thirdly, I am constantly chasing
reports, so I have a measure of validation
for people¹s sightings. I go out
and try to locate the eagle, kite, falcon
reported, preferably with the
person who reports it. Many Brown Falcons,
Brown Gos, Whistling Kites, Little
Eagles and Wedgies are misidentified. No
good saying they should not
be.
Lastly, the ACT Whistling Kite on the cover of AFO Vol 22, 3, 2005 is
easy
to identify because you can sit and stare at it, but would not be easy
if
you saw it in the distance, had a short glimpse in bad light. The ACT
birds
we watch have no windows in the wings as such, so it is not helpful
when
guides use this characteristic to separate them in the
ACT.
Anyway, I hope you are correct about people not confusing these
species. It
will lead to new pairs in 2006 I have
missed.
Regards
Jerry
Message from
Stephen Debus:
Hi
Philip,
I take your points, and I think I queried Jerry's point about
misidentification, but he gave me some examples and I could certainly quote some
of my own. I have to agree with him that sometimes people do misidentify
raptors, though the better/more experienced birders are pretty good these
days.
Why not put your response in the next CBN? I think you
should, because the ACT Little Eagle issue needs more discussion.
Cheers,
Stephen
At 03:58 PM 6/03/2006, you
wrote:
An interesting article in the CBN just out CBN
30(4)141-145, about Little Eagle decline, provides evidence of reduced breeding
by the species locally. That may well be so and I would not doubt it. It is
concerning. However it mentions a comparison with GBS data that supposedly
doesn't support the same conclusion. I hasten to point out that they are
measuring different things. Reported abundance, as surveyed in the GBS, can
increase when suburbs encroach on or come closer to former nesting sites of the
species. The species can still be present in the area but suffer reduced
breeding. Indeed if they are spending less time at a nest, then they may well be
spending more time flying over the suburbs and so be seen more often by GBS
observers. So I don't see the results as conflicting at all. Indeed I suggest
that is what has happened. For a species that may live for many years, there
will easily be a delayed effect in breeding but not in presence. It is
disappointing to see the GBS data mentioned as data not in harmony, when this
approach was not at all necessary without explaining how the two sets of
information fit together. Besides the GBS Report only summarised what the data
shows.
As for the suggestion of
misidentification, I don't agree at all. It can be argued that almost any bird
in any survey can be misidentified but that is hardly helpful. In practise it is
hard to confuse a Little Eagle for anything else locally, apart from a Whistling
Kite and Black Kite. People would not record an ID on the GBS of something as
different as the other species mentioned, if they are that unsure. The culture
of the GBS has always been to be confident of the accuracy of your ID. In any
case, it is obvious from the figures given in the report that the numbers of
GBS observations of the Whistling Kites and Black Kites are so low, that
even if every single Whistling Kite and Black Kite GBS record in the history of
the GBS was in fact a Little Eagle (or indeed real Whistling Kites and Black
Kites recorded as Little Eagles), then the quantitative difference would be so
low it would barely impact on the statistics for the much more common Little
Eagle. Besides the misidentification issue only arises on assessing trends, if
relative rates of misidentification have changed over the years, (in particular
in this case increased). I doubt it. With the increased number and availability
of several good field guides and things like the couple of Raptor ID workshops
that COG has run over the years (to which Jerry Olsen, myself and others
contributed), identification accuracy rates should have improved since 1981, not
decreased. This is another factor consistent with the slight suggestion of
increased status for the Little Eagle in the GBS (more people able to identify
them). However it is not at all inconsistent with a reduced breeding status of
the species. Fair opinion that in the long term that is what is
important.
Philip
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