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Tracking Pacific Walrus: Expedition To The Shrinking Chukchi Sea Ice

12 minutes

(Describer) Beside three black stripes which bend into waves, titles: USGS – Science For a Changing World

(Describer) A creature with long tusks sits on ice.

(female narrator) What's endearing about a 4,000 pound mammal with huge canine tusks? Hear the scientists who work with them:

(male) Walruses love to be together.

(female) They're so gregarious.

(male) They're always checking in and snuggling together.

(male #2) They tend to posse up and have bluff charges and then dive under the water.

(male) When they're concerned, they're first response is to turn to their companions and sniff and nudge them, like they're saying, "Did you notice something?"

(female) Pups are 150 lbs. at birth.

(male) When they swim, the calves hold tight to their mother's back.

(female) It's neat to see something so big, so caring.

(Describer) A few of them bob in the water. Title: Tracking Pacific Walrus: Expedition to the Shrinking Chukchi Sea Ice

(Describer) Dozens of walruses crowd together.


(narrator) Today the Pacific walrus is facing new challenges. This is walrus territory-- the Chukchi Sea, part of the cold, remote Arctic.

(Describer) A satellite view of the Earth zooms in on water between Russia and Alaska.

This vast, shallow sea stretches from the shores of northern Alaska across to Russia.

(Describer) It’s highlighted.

It's the summer range for Pacific walrus females and their young.

(Describer) Stretches of ice float on water.

Over the last 30 years, the Chukchi Sea has experienced a dramatic loss of sea ice due to climate change.

(Describer) The sea ice retreat is shown month-to-month.

Since 2007, this summer ice retreat has accelerated, taking the ice edge into much deeper water. This has created a new situation for the Pacific Walrus.

(Describer) Tony Fischbach:

In 2007, we observed it. We dropped our jaws. It wasn't something we expected soon. This has forced walruses to rest on shore 40,000 at a time. This hadn't been seen before in the United States.

(narrator) Why does this matter to the walruses?

(Describer) Chad Jay:

(male #2) They eat things living on the bottom. Their main prey is clams, but they will take a variety of organisms on the sea floor, often marine worms and large snails and other things. They dive to the bottom and root around in the sediment with their muzzle. The whiskers, the vibrissae, on their muzzle are very sensitive and tactile. They use those as fingers to sweep the bottom.

(narrator) Most of the world's ocean is 10,000 feet deep. Beneath the Chukchi Sea is an immense continental shelf that is only 150 feet deep. This vast, shallow sea is extremely rich in the clams and worms so vital to the walrus.

(Describer) They’re shown on an underwater camera.

Typically, they'll be at the bottom for about seven minutes foraging.

(Describer) Fischbach:

Come back up, breathe for two minutes, go back. Do that dive after dive for hours on end, rest as they move to another clam bed, and continue that. In human memory, Pacific walrus females and their young always rested on sea ice.

(narrator) But now summer sea ice is gone more quickly.

(Describer) It drips.

This leaves female walrus and their calves with no ice to rest on above their favored feeding grounds.

(Describer) Four of them swim together.

Either they travel longer distances to feed, or they have to forage in deeper waters.

(Describer) Title: Gambell, Alaska. In thick coats and hats, and old woman smiles with a young girl.

(Fischbach) Native Alaskans rely very strongly on Pacific walrus. The Yupik word for walrus is "aivik." It's very important, not only for our food,

(Describer) Vera Metcalf:

I use parts to make skin boats, hides, the tusk is made into very beautiful artwork. It's part of our identity, culturally. It's hard to imagine life for many of these people

(Describer) Fischbach:

without having this relationship with walruses. With the increased ship traffic, the changing environment, weather, and climate changes, really concerns us. Because we hope that walrus is there for us to continue hunting.

(Describer) Two hunters stand over a carcass.

(narrator) This longer season of open water has created the potential for greater human presence.

(Describer) A ship goes through the water.

Now there is more opportunity for transocean shipping, fishing, offshore oil and gas development, and tourism.

(Describer) A crowd of walruses lounge together.


Walrus and their calves now contend with increased human presence, just as the security of their summer sea ice disappears.

(Describer) Many of them lie on a beach. A man finds a half-buried carcass. Jay:

We're seeing mortality to calves and young animals because in these large haul outs, there's a disturbance, and the walruses flee into the water and often some of the younger animals get trampled.

(narrator) In 2011 the U.S. Fish and Wildlife Service concluded that listing the walrus as a threatened species was warranted.

(Describer) Several swim in icy water.

Information is being gathered to support a final decision in 2017.

(Describer) A sign shaped like a round plate says “Welcome to Nome”. In a harbor, two men board a boat.

(male) How's it look? All clear? (male #2) Yup, all clear.

(Describer) On the departing boat, Captain Carl Schoch talks on a radio.

(female on radio) Have a good sail. We'll see you in a few days.

(Describer) The tail of a large fish breaks the surface nearby.

(narrator) Society needs to better understand how the walrus is faring.

(Describer) People ride on a Zodiac boat.

USGS scientists are working to see whether the walrus are finding enough food, and where.

(Describer) They get closer to a group.

And to provide information to policy makers to help avoid human disturbances to the walrus. Where are the walrus foraging? Over the past several years, USGS scientists have led expeditions to the remote Arctic to find out.

(Describer) Team members look through binoculars.

(Fischbach) In the Alaskan waters, we have about 95% of the world's walruses. There's perhaps 200,000 to 300,000. During this trip, we'll be applying 40 radios to walruses. The satellite radio tag has a barbed end and attaches in the blubber layer of the walrus.

(Describer) Jay:

It's like a sliver we get in our thumb. With time, it migrates out of the animal and drops off.

(Describer) Another Zodiac boat is lowered into the water.

Essentially, we're looking for walruses hauled out along the ice edge. When we get into any numbers of the them, we'll launch the skiffs and start our tagging.

(Describer) Three team members head out on it, searching for walruses among the ice floes.

Quarter mile.

(Describer) They make a radio call.

(man on radio) Norseman II, go ahead. You wouldn't have an eye on those wallys we left behind?

(Describer) Sarah Sonsthagen:

(man on radio) I'm directing the other boat, but I can take a look. We're tooling around the way point we took and we're not seeing them.

(man on radio) The other skiff is just about on them. Do you have a fix on that?

(male) Roger, we've got them on the AIS, and we'll follow in.

(man on radio) That's my advice. If I see you going the wrong way, I'll redirect you.

(Describer) Scott Hameister takes another radio call.

(man on radio) Scotty, Tony here. We've got two groups. We're holding the position. We'll give you a bearing when you're ready. Very good, thank you. We've gotta find walruses asleep with faces into the wind.

(Describer) Fischbach:

They're very sensitive to smell.

(Describer) He’s in the skiff with Sonsthagen.

We're gonna approach these walruses. They're a little skittish. I'm going radio quiet.

(male) We have to be within ten yards because we have to clearly see the walruses' back.

(Describer) They get closer to a floe full of them.

We then place the radio on their back.

(Describer) They sit up as Fischbach aims a crossbow and hits one in the back with the small radio tag. The skiff backs away. Another call is made.

Did you see the animal we tagged?

(narrator) By the end of the 2012 expeditions, USGS will have tracked more than 400 walrus in the Chukchi Sea,

(Describer) Another is tagged.

with each walrus contributing data about its movement and behavior for the few weeks before the radio tags fall off.

(Describer) One of the tagged walruses dives into the water.

What is the result of the disappearing sea ice?

(Fischbach) On an hourly basis, these instruments show whether the walrus is resting out of the water, in the water, or foraging at the bottom of the sea.

(Describer) They’re shown in illustrations.

The instrument collects that information, summarizes it every hour, and then when the weather satellites pass overhead, it transmits a signal back at my desk.

(Describer) They’re shown as yellow dots on the map.

I'll unfurl this information and build a diary for the walrus. After a period of three weeks, maybe twelve weeks, the walrus's skin rejects the radios.

(narrator) Multiply that by 400 walrus.

(Describer) Jay:

What we've learned so far, is we have been able to map some of the important areas for walruses for foraging. Also how they're migrating through the Chukchi Sea as the sea ice retreats north, we're understanding more how the walruses migrate through the area.

(Fischbach) One project goal is to understand how their time allocation has changed when there's no sea ice to rest on. Foraging from shore, they have a different time budget than when they are offshore foraging.

(Describer) Fischbach:

They're basically having to commute to get their food.

(narrator) Within human memory, female walrus and calves have not been seen foraging from shore. This behavior is a new response to change in their environment. What are the consequences?

(Describer) The yellow dots move on the map.

Now scientists have the information to analyze how much energy is used on long commutes, combined with a reduction in resting time.

(Fischbach) Doing this tracking, we're able to identify the core foraging grounds of Pacific walruses. This has great value to people concerned about new developments in the Chukchi Sea, both of transoceanic shipping that may be occurring in the near future and of oil leasing.

(Describer) Jay:

The walruses are also very important to subsistence users, Alaskan natives. They're very interested in knowing more about what we're finding out and really what's going on with climate change. Hopefully, the work that USGS does helps to sustain

(Describer) Metcalf:

walrus for us in the future.

(narrator) How are the walrus affected by increased human activity?

(Describer) Walruses gather on a floe.

How far must they go to forage?

(Describer) A calf stands in a crowd.

There's no way to learn but up close in their habitat.

(Describer) Two walruses huddle in the water.

And so, in the remote Arctic waters of the Chukchi Sea, scientists continue on tracking the Pacific walrus.

Funding to purchase and make this educational production

(Describer) Titles: A production of - U.S. Geological Survey, Alaska Science Centre and Office of Communications and Publishing. Produced and Directed by Stephen M. Wessells. Written by Donna Matrazzo. Narrator: Cissy Jones. Additional information: Science for a changing world. Funding to purchase and make this educational program accessible was provided by the U.S. Department of Education. Contact the Department of Education by telephone at 1-800-USA-LEARN, or online at

accessible was provided by the U.S. Department of Education:

PH: 1-800-USA-LEARN (V) or WEB:

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Now Playing As: Captioned (English) (change)

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Summer ice retreat in the Chukchi Sea between Alaska and Russia is a significant climate change impact affecting Pacific Walruses. Scientists follow walruses in their summer sea ice habitat and show how United States Geological Survey (USGS) biologists use satellite radio tags to track their movements and behavior. The information identifies areas of special importance to walruses during sparse summer sea ice.

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