Bald Eagle

Bald Eagle

Today's News Report Your Sightings How to Use Journey North Search Journey North

Western Bald Eagle Migration Update: February 24, 1999

Today's Update Includes:

Field Notes from Biologist Jim Watson

To: Journey North
From: Jim Watson

Hello Students:
Winter Range
as of 2/22/99

Winter is slowly transitioning into spring here in western Washington. There are still 30 eagles or so in my study area on the upper Skagit River. Take a look at Eagle #12's data and notice how her movements have changed over the last few locations. She is starting to move around Puget Sound, much like she did at the end of last winter before she moved north.

Today's Satellite Data

The salmon that wintering eagles feed on along the major rivers finished spawning 3 or 4 weeks ago. Now all that is left from their remains is a scrap of a backbone, a piece of skin, or maybe, a whole carcass that was caught on a log under the water but finally washed up to the river bar. If you happen to be the lucky eagle in the right place at the right time, you might find such a carcass...but you can't be too picky about how it smells or tastes, since it's not very fresh. Other eagles have moved downriver into Puget Sound (locate Puget Sound on a map) where waterfowl are found, or to the fields along the Sound to feed on cattle carrion at large dairy farms where cows are birthing in the spring.

The urge to migrate may also make the eagles restless, and cause them to increase local movements before migration. (Biologists refer to this urge as "pre-migratory restlessness".) Changing daylength, and seasonal changes in weather, contribute to pre-migratory restlessness.

Check out the new locations for Eagle #18. His locations are important in our study since he has spent several weeks on a river that none of our other study eagles have used. Do you think he'll stay on the east side of the Cascade Mountains before he migrates northward? Stay tuned.

Jim Watson

Washington Department of Fish and Wildlife

Spring Fever in the West? Challenge Question # 4
"What two factors does Jim Watson describe that may contribute to an eagle beginning to move around the wintering area, after remaining in the same general location for much of the winter?"

(To respond to this question, please follow the instructions below.)
Wandering Around Washington?
Discussion of Challenge Question #3
Last week we asked, "Which eagle seems to be wandering around Washington? If you plot this eagle's movements since January 21 or 22, how many miles has it traveled? Students in what town might have seen it, if they looked overhead on Sunday, February 7?"

Wow, that was a VERY hard question-and these 5th grade students in Omemee, Ontario got it right! (We promise mapping will be much easier when the eagles begin to migrate.)

"We answered your question in three parts--The eagles that are wandering around Washington State are eagles #12 & 18. We used a lot of maps to get this answer and plotted the eagles' data on our map. Eagle # 18 travelled 50.283 km. south and 229.5 km. east. We found this answer by subtracting the two latitude lines, we then multiplied the answer by 111 because every degree of latitude equals 111 km. We were not able to find the town above the coordinates because we could not find a map detailed enough."
Tyler & Kyle, Scott Young Public School
Omemee, Ontario
44.33 N, -78.5 W

If they'd had a better map, we know they'd have said that the name of the nearest town was "Inchelium", WA. (Click on face of map to enlarge.)

They're so smart, we'll see if we can catch them on this one...

Distance as the Crow Flies--and the Eagle?
Today's Winter Range Map shows exactly where Eagle #18 has been wandering. The chart below shows the distance between each place the satellite captured a reading:

Eagle #18's Travels
Date Lat(N) Long(W)



01/22/99 48.51 -121.50



01/26/99 48.58 -121.36



01/30/99 48.51 -120.85



02/04/99 47.94 -118.33



02/07/99 48.06 -118.32



02/11/99 47.73 -117.71



02/17/99 47.84 -117.74



02/22/99 47.80 -117.85




Challenge Question # 5
As the crow flies, what's the total distance between all the places where the satellite received readings from Eagle #18? Explain why the EAGLE actually may have flown further. (Clue: Describe what happens between satellite readings.) But if that's too hard try this: What is the name of the river Jim Watson says Eagle #18 is visiting?

How to Respond to Today's Challenge Questions

Please answer ONLY ONE question in EACH e-mail message.

1. Address an e-mail message to:
2. In the Subject Line of your message write: Challenge Question #4
(or Challenge Question #5)
3. In the body of EACH message, answer ONE of the questions above.

Copyright 1999 Journey North. All Rights Reserved. Please send all questions, comments, and suggestions to our feedback form

Today's News Today's News Report Your Sightings How to Use Journey North Search Journey North