a bioindicator indicates biological or animal species which, because of their ecological characteristics, constitute the early index of biotic or abiotic modifications of the environment due to human activities (ex: lichen).

(Bioindicateur) A bioindicator (also biological indicator) is a measure, an index of measures, or a model that characterizes an ecosystem or one of its critical components. It may reflect biological, chemical or physical attributes of ecological condition. The primary uses of an indicator are to characterize current status and to track or predict significant change. With a foundation of diagnostic research, an ecological indicator may also be used to identify major ecosystem stress.(Adapted from U.S. Environmental Protection Agency.)

An organism and/or biological process whose change in numbers, structure, or function points to changes in the integrity or quality of the environment.

a species that serves as a representative sample of its ecosystem

Bioindicators are species or chemicals used to monitor the health of an environment or ecosystem. They are any biological species or group of species whose function, population, or status can be used to determine ecosystem or environmental integrity. An example of such a group of organisms are the copepods and other small water crustaceans present in many water bodies.