Roy Moffitt: Walrus and Polar Bears on Ice, August 20, 2018

NOAA Teacher at Sea

Roy Moffitt

Aboard USCGC Healy

August 7 – 25, 2018

 

Mission: Healy 1801 –  Arctic Distributed Biological Observatory

Geographic Area: Arctic Ocean (Bering Sea, Chukchi Sea, Beaufort Sea)

Date: August 20, 2018

 

Current location/conditions:

Evening of August 20 – North west of Barrow Canyons, Beaufort Sea

Air temp 28F, sea depth 1914 m, surface sea water temp 31F (72.5N are furthest point north)

 

Walrus and Polar Bears on Ice

In the last couple of days we have seen two of the Arctic’s most notable mammals on the ice, the walrus and the polar bear.  Below is a picture that I took of a large group of walrus that floated near the ship on the evening of August 19th.

These walrus were just the beginning of an even larger group floating up on the ice.  Walrus like to rest on the ice in between feedings off the ocean floor.  Walrus will eat many items off the shallow sea floor, this location is about 60 meters deep.  Their favorite foods are bivalve mollusks, including clams.  The walrus will not break the clams’ shells but suck out the food with their powerful suction capabilities.  More terrifying is that the walrus will occasionally do the same to some sea birds and seals.  Walrus have relatively few teeth besides their tusks.  If they catch larger prey such as a bird or seal, they will suck out the good parts just like a clam.  Male walrus can grow up to be over 4,000 lbs.  Add these facts together and these cute animals become a little more frightening.

Walrus on Ice
Walrus resting on sea ice

Walrus are common in the northern Chukchi Sea this time of year and typically have been known to migrate south in the winter. In a science presentation held onboard our ship, marine mammal scientist, Catherine Berchok, shared acoustic data from her moorings that documented recordings of walrus in the northern Chukchi Sea in the winter. Previous surveys have not typically recorded a presence of walrus in this region as usually these mammals need a mix of ice and open water for feeding, though they can break through winter ice for breathing.  Scientists now have additional questions for further investigation. Why are these walrus here in the winter? Have the walrus changed to a seal diet?  These are questions that are still unanswered.

 

Counting Walrus

 

Walrus dot the seascape
Walrus dot the seascape
The bridge of USCGC Healy
The bridge of USCGC Healy

On the evening of August 17th, we came across a large group of walrus (see image above).  Scientists specializing in mammal and bird observation were estimating the amount of walrus we observed.  Each of the dark blotches on the ice in the fog were all groups of walrus.  The larger groups contained 50-80 walrus while the smaller ones were around 20.  Standing high up on the bridge with cameras and powerful binoculars mammal observers, Jessica Lindsay and Jennifer Stern, estimated the total number to be around 1200 walrus!

 

Finding Polar Bears

 

Polar Bear
A polar bear stands on sea ice

From high up on the ship’s bridge (shown in the above picture), mammal observers and bird observers armed with binoculars are always present in daylight hours when the ship is moving. Bird observer Charlie Wright has quite the trained eye for spotting birds and also polar bears.  A couple days ago he spotted a polar bear approximately 4-5 miles away.  While looking through binoculars, all I could see was a tuft of fur, and then only when I was told where to look.  To me it was like, finding a polar bear in a snowstorm.  Last night Charlie spotted another one. The polar bear pictured above was much closer, perhaps a mile away.  At first, we observed the bear curled up on the ice, but then it stood up and walked around.  The light was dim and the weather was foggy during my observation, but if you look closely at the picture you will see that the bear looks quite plump after a spring and summer of feeding.

 

Today’s Wildlife Sightings

Snow on Healy
Snow on the bow of the Healy

Normally I would focus on a bird, fish, or mammal in this section, but since I focused the entire blog on mammals I want to take this opportunity focus on snow sightings.  We are now actually in one of the drier places on earth. Even though it seems like it is always cloudy and foggy usually only small amounts of precipitation fall here.  Temperatures have been below freezing for a couple days and we have experienced some snow showers but they do not last for long.  Overnight it was enough to dust the Healy with snow as shown below.  Either way I cannot say I experienced snow in mid August before!

 

Now and Looking forward

We will be leaving the deep Arctic shortly and heading south through shallow seas towards our last study area.  Along the way the number of whales, walrus, and birds may increase along with the increased food supply from the shallow sea floor.

On a sad note that means we are leaving the ice and headed south.  So I leave the ice by sharing with you this picture.  Though it was dim light and a bit fuzzy I saw a walrus on its back soaking in the Arctic weather by its ice beach umbrella.

Walrus Ice Umbrella
Walrus relaxing on its back beneath an ice “umbrella”

Roy Moffitt: Life on a LEGO, August 14-15, 2018

NOAA Teacher at Sea

Roy Moffitt

Aboard USCGC Healy

August 7 – 25, 2018

Mission: Healy 1801 –  Arctic Distributed Biological Observatory

Geographic Area: Arctic Ocean (Bering Sea, Chukchi Sea, Beaufort Sea)

Date: August 14-15, 2018

 

Current location/conditions:

Evening August 15 – North- Northwest of Wainwright, Alaska

Air temp 35F, sea depth  47m , surface sea water temp 32.2F

 

Life on a LEGO

The LEGO is a nickname given to the large green plastic pallet-like mooring. Their retrieval from the sea floor is pictured here.  This equipment was retrieved after being deployed for a year on the sea floor in about 40 meters of water.  The mooring is called a DAFT (Direction Acoustic Fish Tracker).  On the DAFT there are instruments that measure ocean temperature, salinity, and pressure.  The primary instrument is an echo sounder that records any schools of fish that may pass overhead.

Lego Retrieval
Retrieval of the “Lego,” a large plastic mooring that has spent the past year collecting data at the ocean bottom

What the DAFT was not designed to do, but does well, is catch sea life. The fiberglass pallet has 1 1/2″ square holes in it that allow water to pass through on retrieval and it also catches sea life as if it were a net. Yesterday we pulled two of these “Legos” from the sea and they were covered with marine life. The most remarkable sight were the large blue king crabs, (around half dozen on one pallet). Here I am holding one of the bigger ones– such awesome looking creatures!

Roy and crab
TAS Roy Moffitt holding a blue king crab

On the smaller size, we found a hermit crab (shown here hiding in a shell).

Hermit Crab
Hermit Crab

Also on board were many sea stars. Most were the Brittle Stars. This is the picture of the sea star with the small legs. I think they are called the Brittle Stars because when I tried to gently remove them from the mooring, sadly their legs kept breaking off. There were dozens of these on the mooring.

Sun Star
Sun Star

There was another sea star with nine legs. It was very pretty and looks like a drawing of the sun. Not surprising, I found out this one is called the “Sun Star.”

Some not-so-pretty items on the moorings I like to call “mooring acne” are called tunicates. These are filter feeders and come in many different forms.

The one on my hand looks like a giant pimple and when you try to take it off the mooring it squirts you in the face. Not surprisingly this tunicate is called the “Sea Squirt.”

 

Think about it…

All of the life on the Lego mooring was sent back to the sea to hopefully find a new home.  The Lego pallet mooring mentioned above is not large, about 4 ft by 6ft.  The mooring in this story was only in the ocean one year and became the home of the above mentioned marine animals – crabs, sea stars, tunicates, and also thousands of barnacles!  One tiny piece of the sea floor contained all this life! Imagine how rich in life the entire unseen ecosystem is in the Chukchi Sea!

 

Today’s Wildlife Sightings

For the last two days, I saw several walruses. Pictured below is one that popped up by a piece of ice.   Teaser – look for a future blog focusing on walrus and their habitat.

Walrus by ice
A walrus pops its head up above water near a piece of ice

 

Now and Looking forward

We are now seeing small bands of pack ice and individual pieces of ice called “growlers”.   Sea ice has not interrupted science operations, as of today. There is plenty of open water so far. We should see ice of different concentrations for the rest of the trip as we continue to head north.  Look for future pictures and some of the science on sea ice coming soon. For now here are a couple pictures from August 15.

Growlers in fog
“Growlers” – the view looking from the deck of USCGC Healy down into the fog
Walrus broken ice
Another view of the walrus, swimming near broken up ice

 

Maggie Prevenas, April 18, 2007

NOAA Teacher at Sea
Maggie Prevenas
Onboard US Coast Guard Ship Healy
April 20 – May 15, 2007

Mission: Bering Sea Ecosystem Survey
Geographic Region: Alaska
Date: April 18, 2007

Species Profile: The Walrus

Yesterday the helicopter crew flew over some walrus. Walrus are touchy feely kinda animals. They love to get together in great big piles and just sprawl all over each other. It’s also a way they keep warm. You can read more about the walrus below.

Scientific name: Odobenus rosmarus

This healthy walrus is hanging out in its favorite place, the ice!
This healthy walrus is hanging out in its favorite place, the ice!

 

Everyone knows what a walrus looks like! Its long ivory tusks are used for many things, including protection from attack by polar bears, killer whales and local hunters in kayaks.

Walrus are very slow on land because they are so big and clumsy, but in the water they are very fast and strong.  They can dive down 300 feet to retrieve their favorite food, clams, from the sea bottom. A walrus can eat 4,000 clams in one feeding!

Air sacs in the walrus’ neck allow it to sleep with its head held up in the water. Nursing females use this standing position as they nurse. The pups, born approximately every two years, nurse upside down.

Walrus will dive into the water at the faintest scent of a human.  Walrus numbers were very reduced by commercial hunters until 1972 when the Marine Mammal Act started protecting them.  Now only native people in the Arctic may hunt them and the populations have grown in size. Native peoples in the Arctic hunt the walrus for food and put every part of its body to good use. They use the tusks for the delicate art of carving called “scrimshaw.”

 

Uglat is walrus poop. Scientists can tell where walruses have been by these dark brown patches. They can also tell what they’ve been eating.
Uglat is walrus poop. Scientists can tell where walruses have been by these dark brown patches. They can also tell what they’ve been eating.

 

DESCRIPTION: Walruses are large animals with a rounded head, short muzzle, short neck and small eyes. They are able to turn their hind flippers forward to aid in movement on land. Their front flippers are large and each has five digits. Males have special air sacs that are used to make a bell-like sound. Both males and females have large tusks that are used for defense, cutting through ice and to aid in getting out of the water. The tusks can be more than three feet long in males and about two and a half feet long in females. Walruses are cinnamon brown in color.

SIZE: Females are smaller than male walruses. Male walruses stand up to five feet tall, are nine to 11 feet long and weigh 1,700 to 3,700 pounds. Females weigh 880 to 2,700 pounds and are seven to ten feet long.

POPULATION: 250,000

LIFESPAN: Walruses can live for 40 years.

RANGE: Coastal regions of the Arctic Ocean and adjacent seas.

HABITAT: Moving pack ice in the shallow waters found near land, coastal beaches. They spend the majority of their time in the water.

FOOD: Clams, mussels and other bottom dwelling organisms that are located by their sensitive whiskers.

BEHAVIOR: Most groups of walruses migrate north in the summer and south in the winter. During the nonbreeding season, males and females tend to stay in groups segregated from one another. Many interactions between walruses are agonistic and may end in fighting.

OFFSPRING: Walruses breed in January or February. Following a 15 to 16 month gestation, a single calf is born. Females are very protective of their young. Female walruses help one another in raising calves. Babies are weaned from their mother at about two years of age.

THREATS: Historically, walruses were hunted commercially for their ivory tusks, oil and hides.

19th Century Naturalist Edward Nelson Recounts:

“To many of the Eskimo, especially on the Arctic shores, this animal is of almost vital importance and upon Saint Lawrence Island, just south of Bering Straits, over eight hundred Eskimo died in one winter, owing to their missing the fall Walrus hunt.

To these northern people this animal furnishes material for many uses.  Its flesh is food for men and dogs; its oil is also used for food and for light in oil lamps and heating the houses.  Its skin when tanned and oiled makes a durable cover for their large skin boats; its intestines make waterproof clothing, window-covers, and floats.  Its tusks make lance or spear points or are carved into a great variety of useful and ornamental objects, and its bones are used to make heads for spears and other purposes.”

This material taken directly from the following URLs, just copied and pasted. Make sure you give them credit should you use it in a report!

http://www.mnh.si.edu/arctic/html/walrus.html

http://www.kidsplanet.org/factsheets/walrus.html