Ecosystems: The Arctic Tundra
Ecology: the scientific study of the interaction of organisms with each other and the physical environment with which they interact.
LocationArctic Tundra Locations
· United StatesCharacteristics of the Arctic Tundra
· Extremely cold climate
· Low biotic diversity
· Simple vegetation structure
· Limitation of drainage
· Short season of growth and reproduction
· Energy and nutrients in the form of dead organic material
· Large population oscillationsClimate and Density Independent Factors
· The winter temperatures - average about -30 F throughout most of the true Arctic including the North Pole. The coldest weather occurs in northeastern Siberia. There,January temperatures average -40 F, and have reached -93 F. Most other parts of Siberia and the sub arctic sections of central Asia, Canada, and central Alaska have an average winter temperatures of about -20 F. The mildest winters occur in the coastal regions of the Pacific Oceans, where January temperatures average about 30 F.
· These same regions have mild summers, with average temperatures of about 45 F. The warmest summers occur in the inland regions of Siberia, Alaska, and Canada. July temperatures there average around 60 F. Weather stations have recorded temperatures of 90 F and above in these regions.
· Winter storms - develop chiefly in two areas where the barometric pressures remains low. One of these areas, called the Aleutian low, extends from eastern Siberia to the Gulf of Alaska. The other, the Icelandic low, covers central Canada, half of the Arctic Ocean, and parts of the North Atlantic Ocean and northern Europe. Storms beginning in these areas tend to travel from northwest to southwest.
· Rainfall - in many arctic regions totals six to ten inches a year, including melted snow. This is less rain than falls on some of the world's greatest deserts! Much of the arctic has rain and fog in the summer. In spite of the low annual rainfall, arctic lands may be very wet underfoot because the moisture evaporates slowly and drainage conditions are poor. There is also a lot of permafrost, ice that never goes away in the ground that is usually about five feet deep.
· Natural Disasters – Melting of snow, and huge blocks of ice falling into the ocean.
Abiotic & Biotic FactorsAbiotic
- Strong Winds
- little precipitation
- short summer days
- very long and cold winters
- poor soil
- permafrost (a layer of permanently frozen subsoil)
- Plants like Heaths and mosses have to adapt to the very long and cold winters because the sun does not come up in the winter
- Wildlife like arctic tundra animals include snowy owls, reindeer, polar bears, white foxes, lemmings, arctic hares, wolverines, caribou, migrating birds, mosquitoes, and black flies.
· Dwarf shrubs
· Perennial Forbs
· Labrador Tea
· Other various small plants and trees…
Primary Consumers (Herbivores)
· Arctic hares
Secondary Consumers (Smaller Carnivores)
· Arctic foxes
Tertiary Consumers (Larger Carnivores)
Quaternary Consumers (Omnivores)
· Polar BearsDecomposers
· Bacteria, the prime decomposers throughout the world, may be found in tundra.
· Mosses, lichen, and fungi are also active decomposers but things take a long time to decompose in the tundra because there is only a short window of temperatures warm enough to allow activity.
The water cycle in the Arctic Tundra biome has the general characteristics of the normal water cycle, but differs when the extreme temperature is added. Although there is little actual rainfall in the arctic, the snow does melt in the sunlight, thus renewing the process below.
This cycle is made up of a few main parts:
evaporation (and transpiration)
Poaching in the tundra is a serious problem. In our poaching experience, the poachers kill the polar bears. With the polar bears now endangered, the arctic fox, and arctic wolves move to the top of the food chain. This thus creates an abundance of those predators, and in turn kills of the rabbits, and other herbivores. This disturbance is serious and needs attention from active organizations, and the government.
Species in the EcosystemPolar Bears
· Population- 21,000-28,000
· Nutritional Requirments- Polar bears primarily hunt seals, especially ringed seals, but also bearded harp), and hooded seals On occasion, they also attack larger animals, such as walrus and beluga whales, and eat carrion. Small animals and vegetation, if available, supplement their diets during food shortages
· Habitat- Most polar bears live on ice where it meets open water. Some polar bears live at least part of the year on actual land, after winter ice and snow melt. Unlike other bears, they inhabit habitats virtually free of vegetation
· Ecological niche- The polar bears niche is to eat walruses, fish,and seals
· Factors- Extreme weather, shortage of food
· Symbiotic relationship - Predation
· Growth pattern -Logistic- With polar bears being an endangered species the carry capacity can’t be determined.
· The chart to the right represents a small portion of the polar bear population in the actic.
· Usefulness to humans- Hunted for fur, and for game.
· Disturbance- They are endangered from being poached.Gray Wolf
· Population- 7,000 to 11,200
· Nutritional Requirements- Ungulates (large hoofed mammals) like elk, deer, moose and caribou.
· Wolves are also known to eat beaver, rabbits and other small prey. Wolves are also scavengers and often eat animals that have died due to other causes like starvation and disease.
· Habitat- Arctic: along the northern edge of the North American continent and northward to the North Pole, as well as along the eastern and northern shores of Greenland.
· Ecological niche- Keeps small herbivores in check, and balances the food chain
· Population Factors- Extreme weather, shortage of food
· Symbiotic relationship - Predation
· Growth pattern – Logistic, carrying capacity is 7 per square mile.
· No specific usefulness to humans
· Disturbance - Gray wolfs are now the top predator on the food chainArctic Hare
· Population- Biologists have determined that Arctic hare populations fluctuate in a common cycle of low and high numbers, as do snowshoe hares farther south.
· Nutrional requirments- The food they eat is mostly willow - the leaves, shoots, bark and roots - and grasses, flowers, saxifrage and crowberry.
· Habitat- The arctic hare likes to live on the rocky slopes and upland tundra of the Arctic. They like to live in groups. They don't like to live in low places or wooded areas.
· Factors: Number of wolves in the area, and the extreme climate.
· Symbiotic relationship – Predation of plants
· Growth pattern - Exponential
· Hunted for food, fur, and game.
· The result of the disturbance has also led to over hunting of the arctic hare by its predator the gray wolf.Arctic Fox
· Population – between 150,000 and 250,000. As of 2007.
· Nutrional requirments- Arctic fox feed primarily on small mammals, including lemmings and tundra voles. Fox denning near rocky cliffs along the seacoast often depend heavily on nesting seabirds such as auklets, puffins, and murres.
· Habitat- the Arctic fox lives in a den, caves or burrows that they dig in the side of a cliff. During winter they often bury into the snow for protection.
· Ecological niche- The Arctic fox lives in a den, caves or burrows that they dig in the side of a cliff. During winter they often bury into the snow for protection, their job is to keep the herbivore population in check.
· Factors- Number of plants and herbivores, extreme climate.
· Predation of smaller animals
· Logistic growth pattern
· Arctic fox have very warm fur that can be used for clothing and can be sold or traded.
· Arctic fox have become the top predator in their cosystem do to the poaching of polar bears.Moose
· Population- 150,000
· Nutritional requirements- In warm months it eats the leaves, twigs and buds of hardwood and softwood trees and shrubs. It also feeds on aquatic plants like water lilies. In the winter the moose browses on woody plants like the twigs and bark of willow, balsam, birch, aspen and dogwood trees.
· Habitat- The moose lives in forested areas where there is snow cover in the winter and nearby lakes, bogs, swamps, streams and ponds.
· Ecological niche- To keep plant rate down.
· Factors: The amount of plants and berries in the area, amount of other males in the area, extreme weather
· Mutualisic- Canada Jay's are often seen eating fleas and ticks off of moose. The relationship, bird gets fed, moose has less parasites living on and about it.
· Logistic- The carrying capacity is set at 3 per square mile.
· Usefulness to humans: Provide food and game.
· The disturbance would eliminate polar bears, which would not directly affect the moose, but may increase the amount of food available.
Effect of the Disturbance on the Species of the EcosystemPolar Bears
· Endangered/extinct. If poaching of polar bears continues without regulation, the species will become endangered, then extinct.Arctic Fox
· Increased. The arctic fox population will increase due to a decrease in the polar bear population because the animals the polar bear eats will now be prey for the fox.Gray Wolf
· Increased. The gray wolf population will increase because of the lack of a higher predator. This could be harmful to the ecosystem because the increase in wolves will decrease the rabbits, thus creating a gap in the food chain.Arctic Hare
· Threatened. The arctic hare population will definitely decrease. With the polar bear gone, the arctic fox and the gray wolf will increase in population, thus creating a need for more hares to feed them, but when that requirement is not met, the population will decrease.Moose
· The moose population will most likely increase. This is due to the fact that the food that the polar bear would eat would now be eaten by the moose.