Typical Food Web
When light and temperature conditions of the tundra permit, plant growth begins. Typical plant growth of the tundra includes low growing perennial shrubs and grasses, mosses, and lichens.
Vegetation leads to invertebrate grazers such as grasshoppers, caterpillars and other leaf eating bugs. The increased number of insects draws predatory invertebrates like spiders and carnivorous beetles.
The increased activity of the tundra food web draws larger vertebrates such as birds and grazing animals. Tundra birds maybe year round residents, such as the rock ptarmigan, or migratory from southern regions, like sandpipers and plovers. Caribou herds move into grazing grounds. Ducks and geese arrive and feed on the vegetation. Small mammals such as lemmings take the increased food supply as a sign to begin the breeding cycle.
The increased numbers of vertebrates provide a food supply for carnivores. Predatory birds such as owls and gyrfalcons hunt other birds and small mammals over the open tundra.
Lemmings and wading birds draw carnivores such as Arctic foxes and jaegers. Wolves hunt large grazing animals such as the caribou. If predators themselves avoid being eaten upon death, their bodies will decompose and become part of the earth.
The entire time the tundra food web is expanding, microbes are at work in the soil.
All dead plant and animal remains, and excreted material are consumed by decomposers such as earthworms and turned into soil. In turn the soil will provide the energy for new plant growth and the cycle of the food web on the tundra will begin again.