Caribou Migration Update: April 23, 2003
Today's Report Includes:
Who is Moving and Who is Not?
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Caribou Migration Map
Click on Map to Enlarge |
This week’s map shows a great
variation on the migration. Some animals are doing the northern movement
and some appear to be happy to stay and eat where they are for the time
being. This week we hear from Karsten and Leanne who are using skis to migrate
with the caribou. Read on to hear how they can hardly keep up with the great
numbers of caribou traveling along the migration path. Remember that our
data is not exactly up to date to protect the animals’ locations.
Study the map, or make your own with today's data.
Newly collared Arnaq and Carmen must be migrating buddies. Take a look
at their movements since they were collared. At first separated by only
a few miles, we locate them just meters apart these days. Can
you calculate the distance (in miles) between their sightings on March
10 and 11? Here are the facts:
- 3/10 Helen located at 67.31 latitude and about the same longitude
as Arnaq
- 3/11 Arnaq (called Parks then) at 67.11 latitude
- The distance between every 1.0 degree latitude = 60 miles.
Don't Forget Ask the Expert!
April 11 - 25 Ask the Expert is open for our Caribou Expert,
Don Russell. Your class is invited to pose questions to him. Don has volunteered
his time to answer student questions and sharehis firsthand knowledge about
the caribou he knows so well.
“Being Caribou” Human
Migration Reporting In
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Brutal snow conditions |
After 3 grueling days of skiing in waist-deep snow and more days enveloped
in the lives of the caribou Karsten and Leanne used a satellite phone to
call in a report. The Porcupine caribou are deep in the mountains but they
are definitely headed north to the calving grounds on the coastal plain.
“...The caribou are streaming off in the distance, more following
behind - we’re definitely in the migration right now. The big
question is whether we’re going to be able to keep up because
one night they came right past our tent. They move at night, they move
during the day, they’re moving in this storm. We’re just
hoping we’ve got some chance of moving with them. So it’s
going great, it’s like right out of a book, it’s unbelievable.
We’re calling in every Monday and Thursday with our position to
Parks Canada. The battery charging is working fine right now. Everything’s
going great. We made good choices on the equipment for what we need,
we’re keeping good care of each other. We’re in great, great
spirits and having an excellent time."
Read more about their first weeks on the trail of the Porcupine caribou
spring migration:
On Easter day, 4/20 Karsten reports, “...We’re
at a place called Bonnet Lake at N 68 degrees, 11.344
minutes, W137 degrees, 52.63 minutes. Hoping to get a plane to
land tomorrow if weather cooperates.”
Using your map of North Central Alaska (C-9 recommended maps), or another
detailed map, locate this latitude and longitude. Then answer this:
Challenge Question #16:
“Using geographic terms that include compass directions and geographic
landmarks, describe the location of Bonnet Lake. Why do you think the
Porcupine caribou travel through this region on their way to the calving
grounds?”
(To respond to this question, please follow the instructions
below.)
Stuck in a Rut
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bull caribou in velvet
Credit Amy Gulick |
During the rut, bulls use their antlers as a display of dominance and at
times engage in head-on clashes for the breeding rights to cows. Occasionally
antlers are broken during these encounters or worse yet bulls can, on rare
occasions, become locked, or stuck together resulting in a horrific death
for both bulls due to starvation. Eventually the cells break down beneath
the burr and the antler drops off. This shedding begins after the rut and
for the older bulls it starts as early as mid November. Younger bulls can
carry antlers until April. Pregnant cows retain their antlers until after
their calves are born in June.
Challenge Question #17:
"For what reasons might female caribou keep their antlers during
the winter, while males drop theirs in the fall?
Challenge Question #18:
"Why might the female’s antlers begin to develop after calving?"
(To respond to these questions, please follow the instructions
below.)
Remember, WHEN something happens often helps explain WHY it happens,
so try to think of what kinds of energy that goes into growing antlers
and the different ways antlers can be used. Then guess the reasons for
the differences.
Find out more about antlers: Even try making a pair to display!
Teacher Tip:
Visit
the Reading and Writing Connection for:
Central Arctic Caribou Growth
Rate and Development
Biologists, including Dr. Stephen Arthur are currently working on a study
of growth rates and weight gain of the Central Arctic Herd (CAH) calves
in the area just south of the Kuparuk field in the Prudhoe Bay oil complex.
The area will likely be developed during the next 5 years, and scientists
hope to determine if caribou continue to physically move away from development,
and if this has an effect on calf growth rates and survival.
In March, 2003 Dr. Arthur and a team from the Department of Fish and Game
took to the field to collar some CAH caribou. With this work with the CAH
they hope they might find answers to help understand the effects of oil
development on the Porcupine caribou herd (PCH).
“We were successful in deploying the 26 GPS collars last month,
although one collar seems to have malfunctioned and another caribou
may have died (there was quite a bit of wolf activity in the area where
the caribou were wintering). At any rate, we have at least 24 caribou
cows equipped with the GPS (satellite) collars. We plan to catch and
collar their calves this June (using smaller, expandable radiocollars),
and then compare rates of growth, weight gain, and survival to the amount
of exposure to industrial activity during the post-calving and summer
period.
The scientists’ work will give us one more piece of the puzzle
to determine the effects of possible oil development in the Porcupine
caribou calving grounds in the Arctic National Wildlife Refuge.
Saving the Chisana
Herd from Extinction
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Trans North helicopter
pilot Adam Morivsan of Dawson City helps prepare a Chisana caribou
cow for transport recently. |
Wildlife managers in the Yukon are taking extreme measures to save a rare
caribou herd from extinction. Wildlife officials are implementing the first-ever
captive rearing program for caribou. “We are afraid there could be
a massive die-off of this population,” Biologist Rick Farnell reports.
“They could functionally extirpate within a few years if something
is not done.” Don Russell participated in the set up of this captive
rearing program. He writes, “There is a small herd that spans the
Yukon/Alaska border in the southeast Yukon. It was at one time about 3000
animals and has plummeted to 300. Yukon Government and Canadian Wildlife
Service are trying a bit of a pilot project where we capture and 'hold'
pregnant cows until their newborns are about 3 weeks old and able to escape
predators. This year we captured 20 cows and are holding them close to
there summer range. Calves should be born in late May. The cows were caught
last week (around April 1) so they will have been (will need to be) fed
and protected for close to 3 months. We'll see if it works.”
On a hillside on the Yukon-Alaska border Farnell’s team has constructed
a huge caribou maternity ward for 20 expectant mothers. A 7-ft. curtain
of geocloth fencing keeps the caribou in an predators out. Freeze dried
lichens collected by Yukon school kids and eight tons of specially mixed
reindeer feed will sustain the caribou for the next three months.
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"Caribou in a Bag"
transport system
Credit CA Wildlife Service |
Caribou tagged for project
Credit CA Wildlife Service |
The 7 foot enclosure
area surrounds 22 acres
Credit CA Wildlife Service |
The goal of the captive rearing experiment – the first of its kind
for a caribou population – is not to return the size to 1,800, but
to return a stable mix of young and old caribou to the herd.
Today, the herd is designated special protected wildlife, which affords
the Chisana caribou the highest order of protection under territorial
legislation.
Caribou People
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antler arrow head |
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antler fish
hook |
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antler harpoon
head |
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mits and
kamiks |
It is difficult for people outside the North to understand how deeply northern
people’s survival and identity are linked to the caribou. Evolving
over thousands of years, the caribou hunt is still central to the Gwich’in,
Inuvialuit, and Inupiat way of life in 15 communities on both sides of the
Alaska/Yukon border. Whereas Plains Indians have mythical stories of great
buffalo herds and hunts, the aboriginal peoples in this remote corner of
North America sustain themselves culturally and physically on a caribou
herd that still survives today.
While the Inupiat and Inuvialuit were whalers and fishermen along the
coast as well as hunters of caribou, it was the interior mountain people,
the Gwich’in, who relied almost exclusively on caribou. As many
as ten caribou per family per year provided food, clothing, shelter, tools
and weapons. Hides were tanned, sewn and sealed to make shelters; winter
hides with thick hollow-shafted hairs provided winter clothing, sleeping
pads and blankets; light summer hides were used for bags, drums and summer
clothing. Caribou antlers were used for tools and weapons while sinew
was spun into thread for sewing, suturing and snaring rabbits and birds.
The Gwich’in wasted nothing. Read more about it:
What the Caribou Means to
Me
Linda Hoffman, on the Board of the Porcupine Caribou Management Board (PCMB)
is one of the fortunate people who have witnessed the awe and beauty of
the caribou in their natural environment. Last winter in the Ogilvie Mountains
she watched the caribou and wrote this: “The three caribou
bulls stood alone sky lined on a snow-capped ridge against an ever-darkening
blue sky. Their white manes flowed in the breeze and their expansive bark
stained antlers rose skyward in majestic splendor. You could count every
breath they took as the wind gently whisked away the frozen vapors. It was
a sight I will never forget.”
She wondered what this herd of caribou meant to others. Here is what a number
of the members of the PCMB had to say.
Frank Edwards, Gwich’in Tribal Council: “Elders and
former leaders always stress the importance of the caribou and how the
people should always look after them. The caribou is our lives. We have
to do our part in looking after them.”
Dennis Frost, CYFN, Vuntut Gwitch’in First Nation: “For
thousands of years our people have said “ I vadzaih Lhan chia
va da thah chia”. We cannot do without you.”
Frank Patterson, CYFN, Nacho Nyak Dun First Nation: “A way
of life for food, clothes and tools based on survival. It is a special
spiritual animal that was put on earth for many people to survive on.”
Vince Fraser, Tr’ondek Hwech’in First Nation: “Caribou
herds are one of the important biological indicators of the overall
condition of the environment.”
Antler Antics: Discussion
of Challenge Question #13: “Why do you think Carmen
would have velvet on her antlers in March when Arnaq and many others do
not? Explain how you came to your answer.”
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Carmen showing velvet
on her antlers |
Our caribou Expert, Don Russell gave us insight into the case of velvet
antlers in March. Here is his response:
“Loss of velvet is controlled by hormones. The odd individual
that doesn't shed velvet normally either has a chronic hormonal imbalance
or ate something last summer (toxic substances in plants like in some
legumes) that disrupted normal hormone production.
That's the most likely answer to a phenomenon that may have many causes.
One thing though it doesn't seem to be related to level of nutrition
or age of animals; although some precocious calves that grow substantial
antlers in their first year tend to have tags of velvet into the winter.”
Carmen is of medium age and reported to have a calf at her heel when
captured for collaring in March. The chances are slim that she is pregnant
now.
Many of you predicted that she was pregnant which resulted in her having
velvet on her antlers. This might be true for the cows in early fall,
but unusual for them as late as March.
Thanks for submitting answers Elio at Highview Elementary in Nanuet, NY,
and Lashawn, Brian and Danny at Iselin Middle School.
Baffling Botanical: Discussion
of Challenge Question #14
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Challenge
Question #14
Polemonium
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During the short Arctic spring and summer the plants that burst forth in
bloom must hurry to complete their cycle of bud, bloom, and seed. This season
of warmth is a sight to behold for hikers and wildflower lovers. On Herschel
Island Darcie studied the plant life guided by a vegetation specialist.
Many of you studied the pretty purple flower in the picture in detail using
skills botanists use to identify flowering plants: “The
plant is tall, skinny, with a green stem and purple flowers.”
“We think the flowering plant is a Polemonium, common name Jacob's
Ladder.” Absolutely! The plant species is Polemonium.
Its common name is ‘Jacob’s Ladder.’
How Big are Bou? Comparing
Sizes: Challenge Question #15 Discussion
Our Challenge Question #15 asked
1. “The average caribou in this study has an average total length
of _______. The average total width (wing tip to wing tip) of a monarch
butterfly is about 10 cm. How many butterflies lined up wing tip to wing
tip would it take to span the length of caribou?”
- Average length of the caribou cows in this
study was about 188 cm. It would take about 19 monarchs lined up to
go that distance.
2. An adult female Gray whale is about 50 feet long. How many cm is this?
How many caribou lined up would equal length of a female Gray whale?
- 50 feet equals 1,524 cm. If an average caribou
cow is 188 cm. in length, you would need about 8 caribou lined up to
reach the length of a gray whale!
3. Assuming an adult Gray whale weighs 36 tons, how much more, in pounds,
does it adult weigh than a caribou cow? (Remember, 2000 lbs = 1 ton)
- 36 tons equals 7,200 pounds. So, 7,200 pounds
minus 181 pounds (average wt. Of caribou cow) = 71,818 pounds. The whale
weighs 71,818 pounds more!
4. A monarch butterfly weighs about 0.5 grams. How many butterflies would
equal the weight of one caribou cow?
- Considering a monarch weighs only a half a
gram (.5 grams) and the average caribou cow weighs181 pounds (8,210
grams), you would need 16,420 monarchs to balance the scale.
Thanks for your work! Especially to Mike and Frank at Iselin Middle School!
Fact for the Day
Top Sources of Caribou Mortality: Wolves and disease for adults; golden
eagles, grizzly bears and poor nutrition for newborn calves.
How to Respond to Today's Challenge
Questions:
IMPORTANT: Answer only ONE question in each
e-mail message.
1. Address an e-mail message to: jn-challenge-caribou@learner.org
2. In the Subject Line of your message write: Challenge
Question #16 (or #17 or #18).
3. In the body of EACH message, give your answer to ONE of the questions
above.
The Next Caribou Migration Update Will Be Posted on
May 7, 2003.
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