Date: 3/11/17 3:50 pm From: Roy Lowe <roy.loweiii...> Subject: [obol] Re: Swan ID
Use some caution in using size to differentiate Tundra and Trumpeter swans. Tundra Swans breeding on the Alaska Peninsula are large with their body size and weight overlap with Trumpeters. Some marked birds from this population have been observed on the Oregon coast in the past.
> On Mar 11, 2017, at 10:01 AM, Lars Per Norgren <larspernorgren...> wrote: > > * > > These measurements are averages, so as with Accipiters there's room for overlap. Patient folks sometimes find small groups, family sized, of Trumpeters in a Tundra flock. Dave Irons pointed out a few days ago that these Trumpeter families will stick together within that flock. I'm inclined to believe that Tundra Swans also can keep close company with close relatives in these big flocks, we humans often can't see the difference. Bewick's Swans have more distinctive yellow patches on the beak, making it possible to track some individuals without human markings, collars, leg-bands and so forth. > On Mar 11, 2017, at 9:23 AM, Tim Johnson wrote: > >> Another thing to consider when identifying swans, the trumpeter is a much larger swan than the tundra. Sibley's field guide shows the trumpeter size as follows: Length 60", Wing Span 80", Weight 368 ounces. Compare that to the tundra: Length 52", Wing Span 66", Weight 230. >> >> It helps if the all the swans being identified are mixed together. If there are any trumpeter swans in the mix they should be significantly larger than the tundras. >> >> My experience is that the tundras and trumpeters don't form mixed flocks, however my experience seeing them together is fairly limited. >> >> Tim Johnson >> Salem, OR > > POST: Send your post to <obol...> > JOIN OR QUIT: http://www.freelists.org/list/obol > OBOL archives: www.freelists.org/archive/obol > Contact moderator: <obol-moderators...> >