Abundance is an
ecological concept referring to the relative representation of a species in a particular
ecosystem. It is usually measured as the mean number of individuals found per sample.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.
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