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A/CPB
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WESTERN Bald Eagle Migration Update: May 4, 1998
Todays Report Includes:
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Latest Travels of Western Eagles
Click to see full map.
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Latest Satellite Migration Data
News from Biologist Jim Watson
Hello Students:
Many of the eagles that we are following have ended their journeys this spring. For those eagles that are nesting,
a new journey is beginning...check out this web site to get an "eagle's eye view" of this journey every
15 minutes:
Photo: USFWS
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A Peak Inside the Eagle's Nest
Click here
for live view of
Bald Eagles Nesting In Western Massachusetts
Massachusetts Division of Fisheries and Wildlife
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Shared Eagles
Canadian & U.S. Eagles Cross International Boundaries
As we near the end of our journey, it might be interesting to talk about how the information we have learned this
spring will be used to better protect eagles and their habitats. As is the case with all animals, bald eagles don't
recognize international or political boundaries.
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Photo: USFWS
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What we have learned is that the wintering bald eagle population in Washington includes breeding eagles from Canada
and Alaska. These eagles that may spend from 1-2 months each winter in Washington. Also, from other satellite telemetry
studies we have done, eagles that nest or hatch in Washington (that includes 1160 adults from 580 nests that raise
about 500 young every year), spend from 2-5 months in Canada and Alaska each fall.
It is difficult to figure out how many "Canadian" eagles we feed in Washington in the winter since
our population includes Alaska birds, but 15 of 20 (75%) birds we have monitored in the study were from Canadian
provinces. If that is representative of the whole population, then of the 3,000 eagles that may winter in Washington,
2,250 are from British Columbia, the Yukon Territory, and Northwest Territories.
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Photo: USFWS
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These eagles are part of the 10,000 adult eagles (5,000 nesting pairs) in these Canadian provinces. The Canadian
population of bald eagles has been important to the population recovery of the bald eagle, which is a threatened
species throughout the United States. When bald eagles declined earlier this century from the progression of pesticides
(i.e., DDT) through their food chain, the seacoast of Alaska and British Columbia remained one of the last strongholds
of eagles in pristine habitat.
This abundance can also be a detriment. Since bald eagles in Canada are not the national symbol, and are considered
to be extremely common, they do not receive the same special protection in Canada as in the United States (other
than the birds and nest trees being protected). From our research, however, we have learned that "our"
population of eagles is "their" population of eagles and vice versa. Therefore, it makes the most sense
to manage these eagle populations on a the basis of "flyways", which are more appropriate from the eagle's
perspective.
This requires working cooperatively with biologists from Canada to "overcome" political and international
boundaries and do what is in the bird's best interest. We have begun to do that by providing information to researchers
and provincial biologists (Ministry of the Environment) on areas important to "our" Washington in eagles
in Canada, and where "their" eagles winter in Washington. We exchange information over a bald eagle discussion
page on the internet, which is managed by the University of British Columbia. I am presently engaged in discussions
with researchers as to the need to protect communal night roosts along the flight corridors we have identified
from our satellite telemetry studies.
Providing Canadian biologists with that knowledge provides greater incentive for habitat protection, since "our"
eagles are considered threatened. Understanding the general movements of these international eagles also mutually
gives us the ability to interpret long-term population trends, by understanding where the eagles come from and
when.
Jim Watson
Washington Department of Fish and Wildlife
The Final Analysis
A Look at Spring and Fall Migration from 1997
Now that you've discovered the destinations of Eagles #05 and #16, we'll add to their stories. In our next and
FINAL update, Jim Watson will provide data from each bird's Fall, '97 and Spring, '97 migrations. How do you suppose
their routes will compare from year to year and from season to
season? Before you draw any final conclusions about eagle migration, wait to see how this information adds to the
picture.
The FINAL Bald Eagle Migration Update will Be Posted on May 18, 1998.
Copyright 1998 Journey North. All Rights Reserved.
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