Keystone species - Sea stars Essay Example | Topics and Well Written Essays - 500 words

Keystone species - Sea stars - Essay Example It may increase population of a species or limit it through direct competition for resources or through predation. The sea stars are considered a keystone species in the rocky intertidal habitat because it determines the habitat’s composition. One of its significant effects is its control over the population of mussel. It dictates the population of mussels within the intertidal region that it inhabits. Even though it can predate many other invertebrates in the middle intertidal, its preference of mussels determines the prey’s population in the habitat. This has secondary effects on populations of other species in the middle intertidal. In the absence of sea stars, mussels grow and colonize the middle intertidal. This leads to extinction of other species such as barnacles and large algae in the locality. This means that sea stars control population of different biotic factors and allows for establishment and sustainability of different species in the middle intertidal, a factor that identifies its supreme influence. Sustainable biodiversity is important to an ecosystem. Sea stars affect biodiversity in rocky intertidal by ensuring a fair environment for survival of all factors in the ecosystem. Sea stars achieve this by controlling population of mussels that is a threat to other species in the habitat. By preferring the prey and by overwhelming it in the middle intertidal, sea stars allows for existence of other organisms that mussels would otherwise disadvantage and eliminate from the habitat. Removal of sea stars threatens biodiversity of the rocky intertidal habitat through facilitating dominance of mussels over other species. It allows mussels into the lower zones and this leads to extinction of other species in the region. Sea stars control population of mussels and their removal leads to extensive dominance of mussel that then disadvantages other