Tom Cotner wrote:

>I would like to address a parallel thread--are we as tweeters placing so
>"public" an owl in danger by interferring with its ability to hunt? I
>ask this as I have heard, I hope incorrectly, that the Great Gray owl
>seen by great numbers of people up in Vancouver DIED, apparently having
>starved to death. I will be honest in stating that I have never considered
>that one of the potential consequences of chasing a bird might be its death.
>

This bird did die, I recall hearing that someone found the carcass which
had been munched on by something. However, how does its death have anything
to do with the fact that it was being viewed by birders? In the east, Great
Greys that come south in invasion years are expected to die and many do.
Most probably die before they get as far south as where the birders live.
The regular invasions of Great Greys are due to crashes in populations of
voles up north, most owls that move south are starving, that's why they
move. The fact that a Great Grey Owl starved to death out of range during a
winter when there has been an incursion from the mountains/north should not
be surprising, in fact it is predicted from what is understood about these
movements.

Radio marking these Great Greys on years when they move south is in
essence a good idea as it may help to learn if these birds do make it back
'home' safe and sound to breed after one of these stressful (in terms of
availability of food, not birders) periods. However, one sample point does
not make a research project. If the project has the budget to radio track 10
to 20 owls in the coming winters (decade) and this is the first of a larger
effort then let's back this thing and help it to get off the ground. If it
is just one owl that is to be followed it is unlikely to achieve much or to
tell us much, in fact you could argue that it is a waste of time and effort
which could have been used for some other more focused project. Research
that is not goal oriented in terms of addressing if it will effectively
answer the question it is trying to answer, does not tend to amount to much
in the end. This does not mean that this owl should not have been tagged,
just that it may tell us very little given the amount of effort going into
catching it, tagging it and tracking it. I would like to know what are the
goals of the researcher involved to properly assess the value of banding
this public owl. There are many less glamourous studies that could be done
to figure out what happens to these food stressed owls. For example, if each
one of the 3 or 4 owls reported from the greater tweeters area could have
been watched for a day or two to address how successful these birds were in
hunting we could have learnt something useful. With adequate sampling and a
concerted effort to identify the prey species as well as searches for
pellets we could have estimated the daily intake of food. The energy value
of this food could have been calculated using values from the literature and
we could have arrived at a reasonable assessment of whether these owls were
eating enough to stay alive or not. Sure, 3 or 4 is not a lot, but it
probably would tell us more than one single radio tracked owl, however, its
a little more boring and monotonous.

Just an opinion,

Al.

Alvaro Jaramillo "You are better off not knowing
Half Moon Bay, CA how sausages and laws are made"
alvaro at quake.net Otto von Bismarck,
but I saw it in a fortune cookie!

http://www.quake.net/~alvaro/index.html