Subject: RE: Tundra / Trumpeter swans
Date: Nov 20 04:00:52 1997
From: "Martha Jordan" - marthaj at premier1.net


Hello,
Stan Olson wrote about swans and I have summarized some information as a
response to his questions:

> How true are the following old handwritten notes in my NGS FG, gleaned
from
> some unidentified source(s)?
>
> 1. Tundra swans are usually in flocks in winter / Trumpeters more often
in
> pairs or small groups, or on the periphery of flocks.
Answer: Tundra swans are usually in flocks in winterTundra and Trumpeters
are now equally likely to be in flocks. It is true that more small groups
or pairs alone are Trumpeters, but both species can be found in small,
medium and large flocks--often mixed species. More and more it is
becoming mixed species in the larger flocks. Geographically for example,
in the Skagit Valley, more Tundras are found below SR20, more Trumpeters
above during the main part of the winter season. In the very late season,
Tundras often come above this area. Yet, both species can be found in all
locations, especially if there is any flood event occuring.
Are Trumpeters more likely to be on the periphery - sometimes, but then so
are Tundras in a large group of Trumpeters.

>
> 2. In southwest BC, Trumpeters are more likely to be found near the
ocean,
> preferring estuary marshes / Tundras are more likely to be found further
> inland, up the Fraser Valley. Same for southwest WA and the Columbia
valley.
Answer: Trumpeters in BC are found along the coast and in estuaries.
They also are found in good numbers, several hundred, in the Sumas Valley
(well inland) and north into the fresh water lakes. About 2,000 use the
agricultural fields in Comox as well as the estuary. Very, very few
Tundras have been seen in the Comox or Sumas areas.
In SW WA the abundant swan along the Columbia River is the Tundra. Over
5,000 Tundras winter from above Portland to the Columbia River mouth. The
Trumpeters are primarily found in freshwater area lakes, ponds and marshes.

Trumpeters do use Willapa estuary at the Bear River (southwest corner) and
other river mouths in Grays Harbor such as Grass Creek and Elk River. Up
in the NW corner they are forested wetland birds, using the lakes and
ponds. Trumpeters like forested wetland areas, Tundras prefer the wide
open expanses. Tundras in BC and US have significant night roosting sites
on estuaries - Skagit Bay, Sacramento Delta, etc. In fact, Trumpeters tend
to be fresh water roosters although Skagit Bay is being used more and more.
One of the largest night roosts for Trumpeters is still DeBay Slough,
inland along the river. More Trumpeters are using the Snoqualmie Valley,
inland again.
We are getting more reports of Trumpeters at Walla Walla and along the
Snake River as well as in the Okanagon. Each year brings new information
as the swans expand or change their routes.

> 3. In southwest BC, Trumpeters are the common swan, Tundras not common /
> More Tundras in the Whatcom Skagit area.
Answer: Trumpeters are the more common swan in BC during the winter.
Spring migration is another matter. However, in Whatcom County the
Trumpeter is now exceeding Tundras in numbers. They are about equal in the
Skagit County area. Snohomish County is more likely to be Trumpeters,
although last year it was mostly Tundras for several weeks, then a switch
to nearly all Trumpeters occured almost overnight. I have seen this happen
in the Chehalis Valley- one year about 60 Tundras, the next and succeeding
years all Trumpeters (or at least 99% Trumpeters). Now we see a few more
Tundras here but still the Trumpeters are the dominant species.
As we go south I see Trumpeters increasing at Ridgefield and at Sauvie
Island and into the Willamette Valley of Oregon.

If anyone wants more information, or has other information on swan
distribution, please let me know.
There is definately a shift in swan use over the past 4-5 years. And it
will only get more so with the loss of habitat in the Skagit and Comox
valleys, the two most important wintering areas for Trumpeters on the
Pacific Coast. Tundra swans also have habitat threats in the
Skagit-Whatcom areas and to the south.

Martha Jordan
marthaj at premier1.net