Species with a Large Impact
Some species in an ecosystem play an especially larger role in the ecosystem, often by being the largest or by occupying a unique niche
Types of Important Species
Dominant Species
Dominant species are the species that are either the most abundant or have the highest biomass. The death of a dominant species can drastically effect the whole ecosystem because it usually means a large loss of biomass
Keystone Species
Keystone species are not dominant, but they usually occupy a specific niche that makes them important. Their extinction can cause a chain reaction of disturbance in the ecosystem.
Examples
Sea Otters
Sea otters eat sea urchins which eat kelp. If sea otters are absent, then kelp forests collapse, causing a chain reaction of disturbance
Beavers
Beavers are ecosystem engineers who alter the environment by building dams and thus have a large impact on other species in the ecosystem