Please enable JavaScript.
Coggle requires JavaScript to display documents.
How has the polar bear adapted to survive in the tundra? - Coggle Diagram
How has the polar bear adapted to survive in the tundra?
Location
Found in the regions just below the ice caps of the Arctic
Found across North America, to Europe, and Siberia in Asia
Much of Alaska and half of Canada are the tundra biome
Also found on top of mountains
Latitude is around 60-75, mostly along the Arctic coast of North America, Eurasia and on the coastal margins of Greenland
Cover 1/5 of the earth's surface
Tundras are also found at very high elevations atop mountains, these are called alphine tundra
Climate
the temperatures are frequently extremely cold, but can be warm in the summer
Tundra winters are long, dark, and cold(mean temperatures below 0 Celcius for 6-10 months of the year)
The temperatures in the tundra are so cold there is a layer of permanently frozen ground below the surface(permafrost), which is a defining characteristic of the tundra biome
Precipitation in the tundra is around 150-250 mm a year(including melted snow)
The tundra is usually wet, because the low temperatures cause evaporation to be slower
The temperature in the summer is around 15-18 Celcius
The summer days are long, but often cloudy
Rainfall and snowfall are generally slight due to low vapor pressure of water in the at,osphere
There is at least one month that has an average temperature high enough to melt snow
There is no month with an average temperature that is more than 10 Celcius
Plant, Animal, and Human Life
Food web
A tundra food web begins with the plant species(like dry shrubs, grass, lichens, and moss)
The primary consumers in the tundra include caribou, hares, oxen, and lemmings
The secondary consumers in the tundra include foxes, bears, wolves and whales
Tertiary consumers include snowy owls, and kittiwakes
The apex predator is usually the humans who live in the tundra(the Inu, Yupit, etc.)
Another apex predator is the polar bear, who feeds on seals, and is even known to kill beluga whales. However, they are hunted by the humans who live in the tundra
Predators & Prey
Predators in the tundra include owls, foxes, wolves, and polar bears
These animals eat caribou, lemmings, and hares
Biotic & Abiotic Threats
Abiotic threats
Little precipitation
Harsh climate
Low temperatures
Sunlight levels(plant growth)
Air pollution
Biotic threats
Predators(carnivores/omnivores)
Human influence(hunting)
Polar Bears
Information
It is the largest bear in the world
It is a mammal, and a carnivore
The average lifespan(in the wild) is 25-30 years
It's weight is 900-1600 pounds, and it's head and body is 7-8 feet tall
They eat seals, but they will readily scavenge on marine mammal carcasses and occasionally hunt larger species like walrus
It is an apex predator of the Arctic food web
Females give birth in the winter, usually to twins
Young cubs live with their mothers for 28 months to learn survival skills
Female polar bears protect their young, but receive no help from male mates
They live in the Arctic region and parts of Canada
They are classified as marine mammals because of their dependence of the sea
They are the largest extant(alive) bear species, and the largest extant land carnivore
Mating occurs in spring, and females reproduce at four to eight years of age
Polar bears live 25-30 years in the wild, but in captivity several polar bears have lived more than 35 years
The US government has listed the polar bear as a threatened species since 2008, mostly because of global warming which continues to reduce Arctic sea ice coverage, a prime habitat for polar bears
Adaptations
The polar bear has to swim in the cold water frequently to hunt for prey. It has a thick layer of body fat to keep it warm, and a double-layered coat that insulates them from Arctic air.(Structural Adaptation)
The polar bear has a white coat which provides them camouflage in the surrounding snow and ice. Under the fur, polar bears have black skin, which helps to soak in the sun's rays(Structural Adaptation)
Pregnant females hibernate in the winter to reduce her energy needs to produce milk for her cubs(Behavioral Adaptation)
Their large front paws, which they use to paddle, aer slightly webbed, which makes them strong swimmers and makes it easier to hunt for food in the Arctic waters(Structural Adaptation)
Polar bears have smelly feet, so when females are ready to mate, they can send out signals through the smelly footprints on the sea ice as they are walking(Functional Adaptation)
Polar bears have bumps, or papillae on the bottom of their feet to grip the ice as they are walking to prevent slipping and make it easier to walk on the Arctic ice(Structural Adaptation)
Polar bears frequently nap in a curling position, sleeping with their backs to the wind, to conserve energy used to keep warm in the Arctic weather(Behavioral Adaptation)