Density Dependent Factors: Density Dependent factors are characteristics that are influenced by the size of a population. Density-dependence generally regulates populations within ecosystems that have many species, if they are not stressed by physical conditions. This is not typically true of the tundra. Its extreme climate reduces the number of species that successfully survive there. Even though this is true, species are still affected by predation and competition in the Tundra. Musk Oxen and Caribou can compete for sedges and grasses. Also, when the population of arctic hares increases the population of artic foxes will go up due to increases predation.