NPS Photo

Wildlife like moose have many adaptations to help them survive in Alaska.

What is an adaptation? Everyone has adaptations. Adaptations can change the way you look or the way you behave. Adaptations help a plant or animal to survive the cold, the heat, to find food, to use tools, to hide from predators, and much more.

Sometimes adaptations seem strange, but that is probably why they work so well. Many different kinds of plants and animals can have the same adaptation for surviving a situation. Adaptations are what make us special.

If you are just interested in animals or are looking for information for your Junior Ranger Book this is place to find out more.

ARCTIC FOX
Arctic Foxes have many adaptations like turning white to match the snow in winter. They have sharp teeth and claws for catching and eating their prey. Arctic foxes feed mostly on small mammals, like lemmings and tundra voles. Foxes living near rocky cliffs along the seacoast often eat nesting seabirds such as auklets, puffins, and murres. When food is plentiful, it is sometimes stored among boulders and in dens to eat later. Many foxes venture out onto the sea ice during winter to eat the remains of seals killed by polar bears. Arctic foxes are omnivorous, this is an adaptation that means they can eat both plants and animals. They sometimes eat berries, eggs, and scavenged remains of other animals. Being able to eat more than one kind of food makes it easier to survive if some of your food is no longer around to eat.

CARIBOU
Caribou have adaptations to keep warm, their fur and adaptations to fight off predators, their antlers, but one of their best adaptations is their feet. Caribou have large, almost suction cup like hooves that spread widely to support the animal in snow and soft tundra, kind of like snowshoes. The feet also function as paddles when caribou swim. the edges of the caribous hooves also become sharp over time and helps them to walk on ice if they have to. Caribou have to migrate long distances to find food and because of the weather. You better have good feet if you are going to have to walk to your food.

BELUGA WHALE
Beluga whales are white. Each summer they shed their skin. They remove the old skin by rubbing it on gravel or coarse sand bottoms of rivers. Before they shed, their skin is yellow and scared. After they shed their skin is shiny and white. The beluga can swim forward, backwards and upside down. Being able to swim allows them to escape predations and is one of their many adaptations.

GRIZZLY BEAR
Like most plants and animals, the grizzly bear has several adaptations that help it to survive. The grizzly bear has two very cool adaptations, a physical adaptation (an adaptation that changes the way the bear looks) and a behavioral adaptations it changes the way the bear behaves). The grizzly bear has a big hump at the shoulders (physical adaptation) and it hibernates (behavioral adaptation).

The grizzly bear has a big shoulder hump, long claws. The big hump and long claws of the grizzly bear help it to get food. The long claws are useful in digging for roots or digging out burrows of small mammals. The big muscles that make the hump is an adaptations for digging and for attaining bursts of speed necessary for capture of moose or caribou for food.

In the winter when the grizzly bear's food is covered by snow or gone they enter their dens and hibernate through the winter. Hibernating is a behavioral adaptation, the bears behavior has changed from being active everyday to hibernating everyday. Hibernating makes the grizzly bears body temperatures, heart rate, and and need for energy lower. Their need for food and water is eliminated. The bears are able to live off fat they stored on their body in the summer and fall.

MOOSE
An adaptation of the moose is it babies. A moose can have one or two babies. the mother helps to take care of the baby moose, just like your parents. The cow moose, that is the mother, feeds her baby moose through nursing, until they are big enough to start eating the plants that she eats. Baby moose have wobbly legs when they are born and could not run away if a predator came after them to eat them, so the mother stays with her baby to protect it from predators. Having a mom around is a good adaptation for a baby moose.

MUSKOX
Muskox have a thick fur coat to keep them warm in the winter, but they must also survive their predators. The muskox change their behavior to protect themselves from predators.  When danger approaches, muskox run together. If only one predator is nearby, they form of a line. If several predators surround the group, like a wolf pack, they form a circle with all muskox facing outward. Sometimes a big bull will charge the predator. The muskox’s adaptation to protecting themselves from wolves is very good.

POLAR BEARS
The largest bear in Alaska the polar bear has very special adaptations. Right now they can only live well in one type of habitat, on the sea ice. The polar bear's adaptations to life on the sea ice include a white coat with water repellent guard hairs and dense warm under fur. They also keep their nose and ears small and fur covered to protect them from the cold. Their teeth are made for a carnivorous instead of an omnivorous diet, and hair nearly completely covers the bottom of their feet.

But the polar bear is a recycler too!  It recycles it body heat. You may have guessed the polar bear has white fur to hide on the ice, but the white fur also acts as part of the heat recycling system. But first we must talk about the skin of the polar bear. The polar bear has black skin and white fur. The color black absorbs heat, very important when you live on the ice, but the color white reflects heat. So what happens is as the polar bear gives off heat from its body the white fur reflects the heat back at the skin and the black skin absorbs the heat keeping the bear warmer. A very complicated but cool adaptation.

SALMON
There are many kinds of salmon in Alaska. Depending upon her size, a female salmon can produce 2,000 to 4,500 eggs. That is a lot of eggs.

The eggs hatch during the winter, and the young sac-fry, or alevins, remain in the gravel, living off the material stored in their yolk sacs, until early spring. Then they emerge from the gravel as fry and move into lakes or rivers before returning to the ocean. During this time they are being eaten by predators. With out a parent around to protect them the fry are easy prey. That is why the female salmon lays so many eggs, so at least a few will survive to become adults.

Adult salmon will return to the stream they were born in to spawn after spending one to four years in the ocean.

RINGED SEALS
Ringed seals weigh the most in the winter and early spring when they have a thick layer of blubber under their skin. The blubber serves as insulation and as an energy source during the breeding and pupping season. The females need lots of energy when they are feeding their pups because the milk the mother gives the pups is almost 60% fat. This helps the pups to grow and put on fat very quickly.

SNOWSHOE HARES
Snowshoe hares were made for living in Alaska. During the summer their fur is brown, but for winter it becomes white. Their fur becoming white is an adaptation, it makes it easier for the hares to hide from predators. Their big feet help them to get around in the deep snow, like a pair of snowshoes. Snowshoe hares do not live underground in tunnels or dens. They live under thick brush and in natural depressions.

WALRUS
The walrus has many adaptations too. It has big tusks for defending it territory to mating, thick blubber to help keep it warm in the cold water, it will lay on the beach in the sun if it gets too cold. But one adaptation most of us don't think about is the mouth of the walrus. Walrus eat several different kinds of clams, snails, crabs, shrimps, worms, and occasionally seals. Only the fleshy parts of the clam are eaten. But how do the walrus get the shells open?Some people think the soft parts are torn away from the rest of the clam by strong suction. The mouth of a walrus is narrow, with an unusually high roof, strong thick lips and a thick piston-like tongue. This creates suction kind of like a vacuum sucking the clam out of the shell.