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Tracking "TR," the
rehabilitated swan cygnet
On December 3, 2003, a tundra swan cygnet was released at Eastern Neck
NWR. This young swan had been rescued after falling into an oil impoundment
at Prudhoe Bay in September. She was rehabilitated at the International
Bird Research and Rescue Center (IBRRC), but by the time she was ready
for release, her family group had already left on their fall migration
to the Atlantic Coast! The young swan was transported by Northwest Airlines
to Philadelphia International and then to Tri-State Bird Rescue in Delaware,
where she waited for the arrival of migratory flocks at Eastern Neck.
Named "TR" after the founder of the Refuge System (this was
before we found out that "he" was a "she"), the swan
was fitted with a satellite transmitter collar to relay data on the survival
and movements of a rehabilitated hatching-year swan that didn't physically
migrate. For a chronology of the swan's subsequent travels, go to TR's
Timeline
Update
based on 11/15/04 telemetry data:
Between 11/11 and 11/15, TR and her flock flew from Minnesota - - to North
Carolina! How did they get to their winter destination so quickly? A refuge
volunteer (who's also a pilot) explained that a strong and steady air
current was produced along the edge of a high pressure area stalling over
Ohio. These winds swept clockwise from Minnesota, through the Great Lakes,
past the Chesapeake Bay, and into eastern North Carolina. As much as everyone
hoped that TR and her flock would stage at Eastern Neck NWR this fall,
it's great that they could take advantage of such a helpful tailwind that
enabled TR to fly over 1500 miles in four days and arrive safely at her
wintering grounds this year.
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TR's
Timeline:
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September 13, 2003:
A juvenile tundra swan is rescued after it falls into an oil pit at Prudhoe
Bay. With 50% of its body covered in oil, the swan is rushed to the International
Bird Rescue & Research Center (IBRRC) in Anchorage for treatment.
The cygnet recovers but, by the time it's ready for release, the family
group has already left Alaska on their fall migration to the Atlantic
Coast.
September 29, 2003:
In an effort to reunite the cygnet with its flock, IBRRC staff transfer
the swan - - via Northwest Airlines - - to Tri-State Bird Rescue in Delaware.
Arriving well ahead of the migratory flocks, the cygnet waits at Tri-State
for the tundra swans to show up at Eastern Neck National Wildlife Refuge
(NWR), their major staging site in the Chesapeake Bay area of the eastern
flyway.
December 3, 2003:
Named for the president who founded the National Wildlife Refuge System
100 years ago, "TR" is brought to Eastern Neck to be released
(and is then found to be a female swan, not a male). Although the cygnet
has been around humans more than swans and has rarely flown, TR heads
straight to the migratory flocks - - and to the front pages of the BALTIMORE
SUN and other news media. To document the survival of an oiled bird and
determine the migratory movements of a hatching-year swan that didn't
travel with its family, a satellite transmitter is attached to TR. Every
4 days for the next 18 months, the swan's location coordinates will be
received and relayed by Argos, a satellite company serving environmental
applications worldwide.
December 28, 2003:
The swan stays at Eastern Neck NWR for several weeks, exploring the area
in ever-increasing ranges. Then the satellite data indicate that TR's
headed east for Delaware's coastline, where she remains for another week.
January 6, 2004:
What a difference a day can make: Hourly readings document the swan's
flight from below Salisbury MD, across the Chesapeake Bay, beyond Gloucester
and then Norfolk VA, and finally to eastern North Carolina! Today, TR
has successfully migrated to the winter destination of nearly 90,000 tundra
swans - - and possibly the site of an amazing reunion of this cygnet and
her family.
February, 2004:
TR continues to over-winter with the other tundra swans in North Carolina,
right where she would have been without her September 13 mishap - - but
not without her dedicated rescuers and rehabilitators. She enjoys the
marshes near Mattamuskeet NWR but also ranges throughout the Pamlico Sound,
and occasionally visits the Outer Banks.
March 14, 2004:
On the 101st anniversary of the National Wildlife Refuge System, our Centennial
year swan begins her spring migration! The morning satellite reading shows
her still in North Carolina, then there is a sequence of lost data, followed
by one final coordinate that shows TR -- over Virginia!
March 18, 2004:
The swan has successfully migrated to southern Ontario, near Bird
Studies-Canada's Long Point Bird Observatory on Lake Erie - - a major
staging area of tundra swans during both fall and spring migrations. Whether
TR returned to Eastern Neck NWR during this spring migration is unknown,
since the satellite data set is transmitted only every four days and she
covered a lot of distance between 3/14 (Virginia) and 3/18 (Canada). But
we're looking forward to the possibility of seeing her at the refuge again
next fall. Meanwhile, it's great news to know that this young swan is
heading back to the Arctic tundra where she belongs. But she still has
miles to go.
March 22, 2004:
The swan cygnet is still near Lake Erie, where hopefully she's getting
some rest and nourishment before resuming her arduous journey north. Dr.
Scott Petrie, Research Director of Long Point Waterfowl and Wetlands Research
Fund, reports: "We have ~10,000 tundra Swans at Long Point. Apparently
there are also about 6,000 at the Aylmer Wildlife Area ~50 km NW of Long
Point. Migration within southern Ontario (in and out) is certainly in
full swing. Shannon Badzinski thinks he may have seen your marked bird
(white collar with antennae) at Long Point (on Big Creek) a few days ago."
March 31, 2004:
Today's satellite coordinates first showed the swan mid-Michigan; four
hours later, she was almost across Lake Michigan and approaching
Wisconsin. Each of the coordinates was different, indicating that TR spent
those hours flying. It was only the longitudes that changed, however;
the latitudes varied by just a degree or so -- in other words, she's holding
a steady course along the tundra swans' traditional flyway. During the
4 hours covered by the satellite relay, TR traveled approximately 380
miles at an average speed of 80 mph. Green Bay is a favorite stop-over
for migratory tundra swans in Wisconsin. But TR and her group may choose
to keep going while the winds are so favorable.
April 4, 2004:
Hello, Bismarck! When the satellite last "saw" our swan
cygnet, she was crossing Minnesota during the early morning hours of April
4 and arriving east of Bismarck, North Dakota by 9 a.m. Again,
the longitudes steadily increased, indicating that TR is still on the
move. (Studies have suggested that migrating birds follow a "magnetic
highway" -- but this one seems to be using I-94!) Receiving satellite
data only every four days, we don't know if the swan and her flock stopped
at Green Bay or somewhere else since the Lake Michigan sighting on 3/31/04.
Now that TR has reached the Dakotas, she'll be heading north.
April 8, 2004:
Today's satellite coordinates show that TR is in western Minnesota.
Yes, that's east of Bismarck, not north. But what looks like back-tracking
is actually the movement of this young swan through another major staging
area, the Red River valley.
Since the coordinates are sent every four days, we couldn't know whether
the swans had already staged and left this site when TR's April 4 transmissions
showed her enroute to Bismarck. But apparently TR was just venturing west
while she and her flock were still based at the Prairie Pothole Region
along the Minnesota-North Dakota border. Here, rich wetlands are
offering the migratory swans a diet of high-energy vegetation and high-protein
invertebrates. The April 4 satellite readings had showed TR on the move,
but the April 8 coordinates are all similar -- so this young swan is getting
some rest on her first long journey.
April 12, 2004:
The swan cygnet is still based in the Red River valley area of
Minnesota/North Dakota, but back on the North Dakota side of the
border, not far from Fargo. Tundra swans leave the wintering grounds at
their lowest body weights, so acquiring fat reserves at spring staging
areas such as the Red River valley is crucial to their survival during
the weeks of migration and also during the first few weeks after their
arrival at the Arctic tundra. Continued "R&R" at this vital
wetland is giving TR and her associated flocks a great opportunity to
prepare for the next phase of their migration -- the journey north into
Canada!
April 16, 2004:
The satellite data relayed from the tundra swan cygnet's transmitter the
night of 4/16 to early 4/17 show TR still in eastern North Dakota, with
little change from her 4/12 location near West Fargo. Many migratory
tundra swans exhibit a strong fidelity to this stop-over in the Red River
region, staying from several days to several weeks here each spring. Later
this week, we'll again check on the status of TR's time-out from her travels.
April 21, 2004:
Still in North Dakota, the swan's location has hardly changed the
last 10 days. Fortunately, the satellite readings from the transmitter's
activity level sensor show plenty of movement, indicating that she is
alive and hasn't slipped her collar. Apparently, TR is just waiting for
warmer weather -- and the wind.
Connie Norheim, a member of the Audubon Society of Fargo, ND sent the
following report dated 4/22: "The coordinates look like she's
at Brewer Lake, by Erie, several miles to the west. A friend says a
flock of 200-300 swans has been near her home for the last 2 to 3 weeks.
Further north, it's still pretty cold, and it's not surprising that
they're holing up here for awhile. It got below freezing here in Fargo
last night."
Brad Bortner, Chief of the Fish & Wildlife Service's Division of
Migratory Birds and Habitat Programs (Pacific Region), confirmed weather
conditions and food availability as reasons this young swan and her
flock are dawdling in Dakota: "They'll follow their stomachs
and the frostline," Brad says. "There isn't a lot of
food at the tundra when they first arrive, so they're building up fat
resources."
Dr. Matt Perry, research biologist at the U.S. Geological Service's
Patuxent Wildlife Research Center (Laurel, MD), reminds us that "age
may be a factor in migration timing. Sexually immature swans may be
a little slower." Mature swans try to reach the tundra as early
as weather permits, to ensure a successful breeding season during its
short summer.
April 29, 2004:
On April 28, members of the Fargo-Moorhead Audubon Society visited Cass
County, North Dakota and found a flock of 150 to 200 tundra swans -- including
TR ! A photo (right) taken by Lew Dailey and Connie Norheim
on April 28 show the tundra swan cygnet looking hale and hearty near Fargo,
ND. The April 29 satellite readings show TR moving slightly northwest
within the Sheyenne River watershed. Is the cygnet nearing the
end of her long hiatus in North Dakota?
May 8 - 21, 2004
A cold front hit the Dakotas in early May, but the swan cygnet kept on
the warm edge of the weather system by moving east. Problems with satellite
data made tracking uncertain, but a single data set on May 12 and again
on May 16 confirmed TR's location as being along one of Minnesota's
many rivers, the Big Fork in Koochiching County. The May 21 satellite
data showed her still at this site.
May 29, 2004
TR and her flock have finally left Minnesota
and arrived in Canada, in the southeast corner of Manitoba, near Lake
of the Woods. The swans' recent "holding pattern" and route
may indicate that their destination is the Hudson Bay, not Prudhoe Bay.
Dr. Rich Malecki, research biologist with the U.S. Geological Service's
New York Cooperative Fish & Wildlife Research Unit at Cornell University,
says that "this spring has had a lot of variability."
Although Alaska is reported to have had an early thaw, Rich says "the
word at Hudson Bay is that spring is at least two weeks late, with temperatures
colder than they've been in the last 10 to 12 years. Somehow, the swans
know that."
June 8, 2004
After two lost cycles, the satellite received clear readings from the
swan's transmitter today. During the ten days since the last transmission,
TR has traveled over 500 miles, due north, and is now in northern Manitoba.
Since TR is somewhat past the point where the Alaskan swans normally shift
their direction northwest, her adopted flock may be Canadians heading
for the Hudson. The next transmission should provide the answer.
June 18 and 24, 2004:
TR's transmitter has now shifted to a ten-day timer enabling fewer updates
but longer battery life. However, the 6/18 and 6/24 transmissions were
faulty, each relaying only two signals with conflicting coordinates showing
locations an hour apart but varying up to 250 miles. TR's still in Manitoba,
but the exact site won't be known until a more accurate data set is received.
July 8, 2004
The July 8 transmission had only two sets of coordinates, but they
consistently indicated TR's location as just south of Churchill, Manitoba,
near one of Canada's largest national parks, Wapusk. Described
as a "Hudson-James Lowland Natural Region," Wapusk contains
expanses of inland tundra that provide migratory swans with habitat for
either staging or nesting. This appears to be the final destination for
TR's flock this summer.
Spring 2004 migration summary:
TR's journey began as a fast-paced
event in March, 2004 as the cygnet made it from North Carolina to southern
Ontario in four days, and later raced through 380 miles in four hours
with the help of a good tailwind over Lake Michigan. Then the tempo
tapered into a holding pattern in North Dakota throughout April, and
in Minnesota during May, pending Canada's late thaw. Then in July, TR
arrived at Wapusk National Park near Churchill, Manitoba, and remained
at this site until late September.
TR's not returning to Prudhoe Bay might be a disappointment for us,
but making it to the Hudson Bay is a real success for her. Dr. Scott
Petrie of Bird Studies Canada reports a number of cygnets still at Long
Point Bird Observatory on Lake Erie, young swans that just weren't able
to go the distance and got left behind. But this not-quite-one-year-old
swan has kept the pace - - and perhaps it's fortunate that it was a
relatively slow one - - during her first migration, and has lived up
to her name. Theodore Roosevelt began life as a sickly child but grew
up to be a robust leader and traveler; as this namesake swan matures,
who knows what changes time can bring to TR's future journeys?!
Fall 2004 migration . . . .
. the journey continues!
September 25, 2004
TR left her Hudson Bay summer grounds in Wapusk National Park near
Churchill, Manitoba and arrived at South Indian Lake, Manitoba on September
21, 2004 -- a distance of approximately 200 miles (320 km). Then, over
the next four days, TR traveled approximately 450 miles (725 km) to reach
Lake St. Martin, near Lake Manitoba by September 25.
October 25, 2004
After staying north of the border (near Melita, Manitoba)
for almost two weeks, TR returned to the United States on October 12,
2004 and has since remained in northwestern North Dakota. Here,
TR's Hudson Bay flyway converges with the major migration corridor used
by contingents from Alaska's North Slope (our swan's birthplace) and Canada's
Northwest Territories. Funneling south through Saskatchewan into North
Dakota, these thousands of swans will head east next. And so will TR!
November 3, 2004
Today's telemetry data shows that TR has left North Dakota and is
in Clearwater County, Minnesota. This area is noted as the source
of America's longest and largest river, the Mississippi, which begins
its 2,303-mile flow at Lake Itasca. The Upper Mississippi River basin
hosts tens of thousands of tundra swans enroute to their wintering grounds.
November 11, 2004
The November 7 and November 11 satellite relays show TR still in Minnesota,
but moving east from Clearwater County to Beltrami County. Gary
Huschle, a wildlife biologist at Agassiz National Wildlife Refuge in Middle
River, MN reports that "in addition to the natural lakes and marshes
in this area of Minnesota there are wild rice paddies that are used extensively
by tundra swans during migration. The mild weather we have been experiencing
has allowed many swans to linger."
November 15, 2004
Between 11/11 and 11/15, TR and her flock flew from Minnesota - -
to North Carolina! How did they get to their winter destination
so quickly? A refuge volunteer (who's also a pilot) explained that a strong
and steady air current was produced along the edge of a high pressure
area stalling over Ohio. These winds swept clockwise from Minnesota, through
the Great Lakes, past the Chesapeake Bay, and into eastern North Carolina.
As much as everyone hoped that TR and her flock would stage at Eastern
Neck NWR this fall, it's great that they could take advantage of such
a helpful tailwind that enabled TR to fly over 1500 miles in four days
and arrive safely at her wintering grounds this year.
During the fall migration, tundra swans
often make long-distance flights,
traveling both day and night. TR and her flock certainly did!
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