Maggie Prevenas, April 17, 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 17, 2007

Species Profiles

belugawhale-368x400Beluga Whale

Today a beluga whale was spotted from the helicopter. The whale was swimming in a small open area in the middle of an ice flow. This open water is called a ‘polynya.’ Read on to learn more about these beautiful whales. In the next few days, I will have the chance to add photos from Belugas we see.

What is really cool about beluga whales?

Beluga whales (also called white whales) are known to strand on mud flats without apparent harm. They are able to wait for the next high tide to swim away.

Adult beluga whales have been observed carrying odd objects such as planks, buoys, and even caribou skeletons during calving seasons. It is believed that if a female beluga loses her newborn, she might interact with these objects as a calf surrogate.

Beluga whales have a flexible neck due to cervical vertebrae (backbone) that are not fused, as in other cetaceans. This allows them to move their head up, down, and to the side. Their bulbous forehead, called a melon, is also very flexible allowing them to make many different facial expressions. Movement of the melon is associated with the production of sounds.

Beluga whales are known as the “canaries of the sea” because they produce a vast repertoire of sounds including whistles, squeals, moos, chirps, and clicks. These sounds are used for communication within their social groups and also use to locate prey through echolocation.

What are beluga whales like?

The name beluga comes from the Russian word “bielo” meaning white. Beluga whales live, hunt, and migrate together in pods of a few, to hundreds of whales. Beluga whales are extremely social. In the summer, they are often found near river mouths, and sometimes even venture up river (as far as 621.4 miles (1000 kilometers) in the Yukon River). However, recent satellite tagging research has shown that beluga whales also spend time offshore, diving to depths of at least 1,148 feet (350 meters) where they are likely feeding on deepwater prey.

Where do beluga whales live?

Beluga whales inhabit the Arctic and subarctic regions of Russia, Greenland, and North America. Some populations are strongly migratory, moving north in the spring and south in the fall as the ice forms in the Arctic. As the ice breaks up in the spring, the whales move north again feeding near river mouths and offshore. There are a few isolated populations that do not migrate in the spring, including those in the Cook Inlet, Alaska and the St. Lawrence estuary in Canada.

How many beluga whales are there?

Beluga whales are not considered an endangered species however some stocks are faring better than others. NMML has done extensive work with some stocks of beluga whales including the Beaufort Sea, Eastern Chukchi Sea, Eastern Bering Sea, Bristol Bay and Cook Inlet stocks. You can read more about these stocks in the NMFS Alaska and Atlantic stock assessment reports.

How can I identify a beluga whale?

Belugas are born dark gray. They turn white as they mature sometimes taking 3-8 years to reach their adult coloration. Adult beluga whales can grow up to 16 feet (4.9 meters) long. Females are generally smaller than males. Belugas have large melons and very short snouts. Interestingly enough, unlike other cetaceans, beluga whales also have the ability to move their head independent of their body.

Beluga whales do not have dorsal fins. Dorsal fins would be a major hindrance during the winter when they live in the loose pack ice of the Arctic. A dorsal fin would cause extra heat loss when Arctic animals, such as belugas, need to conserve heat. They do have a tough dorsal ridge which, along with their head, can be used to break ice for breathing holes.

How well can a beluga whale see or hear?

Beluga whales have well-developed, acute senses. They can hear a vast range of sounds and have excellent vision in and out of water. Belugas may have some sense of taste, but they do not have the brain receptors or olfactory structures for the sense of smell.

Belugas often hang in pods. This huge pod was seen on Saturday April 21 by the Ice Seal team as they were recording a transect.
Belugas often hang in pods. This huge pod was seen on Saturday April 21 by the Ice Seal team as they were recording a transect.

What do beluga whales eat?

Beluga whales are diverse eaters, with more than 100 prey species identified including salmon, capelin, herring, shrimp, Arctic cod, flounder, and even crab. They feed in both open water (pelagic) or on the bottom (benthic) and in shallow and deepwater habitats.

How do beluga whales have their young?

Female beluga whales are old enough to reproduce at 4-7 years of age and males at 7-9 years. Beluga whales mate in the spring, the exact time varying geographically. The following year, after a 14-15 month gestation period, females give birth to single calves (and on a rare occasion twins) that are about 5 feet (1.5 meters) long. Calves nurse for at least 12-18 months, but may continue to nurse for another year after beginning to eat solid food.

How long do beluga whales live? How do they die?

Beluga whales are thought to live for 35-50 years. Beluga whales are prey to killer whales and polar bears. They can also die when entrapped by ice.

Some beluga whale populations have been greatly reduced as a result of hunting practices. Historically, large numbers of beluga whales were hunted commercially. Today only subsistence hunting is allowed in U.S. waters. Beluga whales’ affinity for shallow coastal waters puts them at risk as humans alter coastlines and estuaries with pollution, dams, and off-shore petroleum exploration and extraction. Canada’s St. Lawrence Estuary is an example where industrial pollution has caused high beluga whale mortality.

More information can be found on the internet at:

This material was taken word for word from the following website. Please give them all the credit in the world should you wish to use this information in a report.

 

On the hunt
On the hunt

Polar Bear: Ursus maritimus

On board the Healy, there is one helicopter that is being used by the folks from the National Marine Mammal Laboratory to do population studies. Today they went out for two runs. In the first run, the team saw a Polar Bear eating walrus. The photos for polar bear will be added as soon as they become available. If you’d like to learn more about them, read on.

Polar bears live year round near arctic waters hunting seal and other animals, rarely coming on land except on islands and rocky points.  In winter they hunt along the Arctic shelves looking for tasty seals, fish, and even humans!  Their white coats provide camouflage in the ice and snow which make them almost invisible as they stalk their prey.

In winter, when they are far from land they search for breathing holes made by seals.  When the seal comes up for air, the polar bear will kill it and flip it out of the water with a single blow of its great clawed paw! Polar bears are very dangerous, and grow to a huge size and weigh as much as small automobile (1000 pounds). They have longer legs than other bears and large furry feet. These big feet help to distribute their weight as they walk on thin ice in the arctic waters. Polar bears are strong swimmers and can stay submerged for two minutes at a time. Their fur is made of hollow hairs which trap air and help to insulate them in the frigid waters.

After the kill
After the kill

In November polar bears retire to dens dug out of the snow or permafrost. The females remain until the spring when they emerge with one or two cubs who stay with them for the next year and a half. The males spend a shorter time in the dens and may be seen out and about at any time of the year.

19th Century Naturalist Edward Nelson Recounts:

“The Eskimo of Saint Lawrence Island and the American coast are well supplied with firearms which they use when bear-hunting.  In winter, north of the straits, the bears often become thin and very savage from lack of food.

A number of Eskimo on the Alaskan coast show frightful scars obtained in contests with them in winter.  One man, who came on board the Corwin, had the entire skin and flesh torn from one side of his head and face including the eye and ear, yet had escaped and recovered. One incident was related to me which occurred near Point Hope during the winter of 1880-’81. Men went out from Point Hope during one of the long winter nights to attend to their seal nets, which were set through holes in the ice.  While at work near each other, one of the men heard a bear approaching over the frosty snow, and having no weapon but a small knife, and the bear being between him and the shore, he threw himself upon his back on the ice and waited.  The bear came up and for a few moments smelled about the man from head to foot, and finally pressed his cold nose against the man’s lips and nose and sniffed several times; each time the terrified Eskimo held his breath until, as he afterwards said, his lungs nearly burst. The bear suddenly heard the other man at work, and listening for a moment he started towards him at a gallop, while the man he left sprang to his feet and ran for his life for the village and reached it safely.  At midday, when the sun had risen a little above the horizon, a large party went out to the spot and found the bear finishing his feast upon the other hunter and soon dispatched him.  Cases similar to this occur occasionally all along the coast where the bear is found in winter.”

This material was copied and pasted from the following website. Please give them all the credit in the world should you use it in a report or in other ways. http://www.mnh.si.edu/arctic/html/polar_bear.html

Maggie Prevenas, April 14, 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 14, 2007

Species Profiles

Spotted Seal

Studying the spotted seals
Studying the spotted seals

 

Today was our first close encounter with a spotted seal. Spotted seals are the most common ice seals in this area. They are known for their spicy personality.

Where do spotted seals live?

Spotted seals live along the continental shelf of the Beaufort, Chukchi, Bering, and Okhotsk Seas, south to the northern Yellow Sea and west to the Sea of Japan.

How many spotted seals are there?

There is no accurate population count at this time, but it is estimated that there are under 300,000. They are the most common ice seal up in the Bering Sea.

How can I identify a spotted seal?

 

Pups are white and weigh 18 to 26 pounds. This one was a bit heavier.
Pups are white and weigh 18 to 26 pounds. This one was a bit heavier.

Spotted seals are wary and hard to get close to. Adult spotted seals are silvery-gray with dark grey on the back and covered with brown to black irregular spots. Pups are born with a white coat but molt to the adult colors after 3 or 4 months. It is believed they winter in the Bering sea. Following the ice front, they travel north in the spring and summer. They reverse the process and follow the developing ice south in the fall. Spotted seals may get to be 270 pounds, but males and females average 180 to 240 pounds. Length of grown seals is between 4.5 and 5.5 feet. Newborn pups weigh 18 to 26 pounds (8 to 12 kg) and average about 33 inches (84 cm) long.

What do spotted seals eat?

Spotted seals eat many things, depending on the season and their location, including Arctic cod, sand lance, sculpins, flatfishes, cephalopods, and a variety of shrimps.

During the first few weeks after weaning, pups seem to spend most of their time on the ice, but they do not enter the water.
During the first few weeks after weaning, pups seem to spend most of their time on the ice, but they do not enter the water.

How do spotted seals have their young?

Spotted sea pups are born anytime from early February to the first part of May, depending on their location. Pups are white and weigh 18 to 26 pounds. They are nursed for three to six weeks, during which time they more than double in weight. During the first few weeks after weaning, pups seem to spend most of their time on the ice, but they do not enter the water. Spotted seal pups take longer than other ice seals to learn to swim and dive! In the spring, spotted seals will form small groups of a male, female and her pup.

How long do spotted seals live? How do they die?

The life span of spotted seals is believed to be up to 35 years.

The predators of the spotted seal include the polar bear, sharks, Steller sea lions, brown bears, humans and walrus. Wolves, foxes and large birds have been known to feed on pups.

Did You Know? Spotted seal are the only seal that breeds in China!

Maggie Prevenas, April 10, 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 10, 2007

Albatross often mate for life. Photo by Maura Naughton
Albatross often mate for life. Photo by Maura Naughton

Species Profile: Laysan albatross: Diomedea immutabilis

One bird that we expect to find up here in the western part of the Bering Sea is the Laysan Albatross. This is one beautiful bird, large creamy white, and so elegant! It breeds in the Hawaiian Islands, mostly in the isolated Northwestern Hawaiian Islands (NWHI). My students have a great connection to the Bering Sea with this animal as it flies from those small Hawaiian islands all the way up here to find food. They will have the chance to study its diet when they dissect boluses from the chicks bred on Tern Island in the French Frigate Shoals of the NWHI archipelago later on this quarter.

Where can you find the Laysan Albatross?

The Laysan Albatross breeds on isolated islands in the central Pacific Ocean, but is found throughout the northern oceans during all times of the year. They are most commonly seen in the Bering Sea and Aleutian Islands flying low over the waves searching for food.

How large are they?

Laysan Albatrosses are among the largest of all flying birds, having a wingspread greater than 2m (6 ft), but weighing only 10 kg (22 lbs).

What do they eat?

Laysan Albatrosses are specialized feeders on schooling fish and snatch unwary victims from just under the surface. They also eat squid, flying fish eggs, and most unfortunately, lots of plastic marine debris.

What’s pelagic mean?

Birds and other animals that spend most of their lives at sea, and use land only to breed are called pelagic. Once hatched, albatrosses will return to land only to breed, the rest of their life is spent at sea.

How do they sleep?

They sometimes are seen asleep on the water but this makes them easy targets for killer whales and hunters. Most albatrosses apparently sleep while gliding in the air.

This information was copied and slightly modified from this website:

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

Please visit the website and credit them correctly if you use this information.