Abundance

Abundance is an ecological concept referring to the relative representation of a species in a particular ecosystem. It is usually measured as the large number of individuals found per sample. How species abundances are distributed within an ecosystem is referred to as relative species abundances. Abundance is contrasted with, but typically correlates to, incidence, which is the frequency with which the species occurs at all in a sample. When high... more

Abundance is an ecological concept referring to the relative representation of a species in a particular ecosystem. It is usually measured as the large number of individuals found per sample. How species abundances are distributed within an ecosystem is referred to as relative species abundances. Abundance is contrasted with, but typically correlates to, incidence, which is the frequency with which the species occurs at all in a sample. When high abundance is accompanied by low incidence, it is considered locally or sporadically abundant. A variety of sampling methods are used to measure abundance. For larger animals, these may include spotlight counts, track counts and roadkill counts, as well as presence at monitoring stations. Relative species abundance is calculated by dividing the number of species from one group by the total number of species from all groups. less