Stuart MacKay writes:
> Lisa asked about Nasal Disks on Barrows Goldeneye:
>
> >From memory - nasal disks clip on a bit like a lapel badge ar a stud
> fastener . They are "attached" using a plastic strip which passes
> through the gap linking both nostrils - you can see through this BTW.
>
> This technique for marking birds is not that common - it works really
> well with waterfowl where the beaks are relatively large and have a
> flat surface, so the disk doesn't impede the bird's vision. Not sure
> if there are any documented ill effects - first reaction is I wouldn't
> think so.

I was also thinking about adverse effects, specially during the mating
period.

Wouldn't these disks be consider as "inaesthetic" by the marked
birds' potential mates?

I guess that would depend, among other things, on the size of the disks.

Sean, could you (or any informed tweeter) tell us more about the size
and potential adverse effects of these disks?

Thanks

--
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A bird in the bush is better than two in the hand.

Serge Le Huitouze Intelligent Software Group
email: serge at cs.sfu.ca School of Computing Science
tel: (604) 291-5423 Simon Fraser University
fax: (604) 291-3045 Burnaby, B.C., V5A 1S6 CANADA
http://www.isg.sfu.ca/~serge/