Benthic Macroinvertebrate Testing
Biological monitoring of waterways is crucial to the analysis of water quality and ecological health. Benthic macroinvertebrates are defined by the State of Maine's Bureau of Land and Water Quality as "aquatic animals without backbones that can be seen by the unaided eye and typically dwell on the bottom substrate of a waterbody (e.g., rocks, logs, sediment, plants)." Macroinvertebrate testing is used in water quality analysis, often in concert with water chemistry tests. Macroinvertebrates are useful for analyzing the ecological health of bodies of water because many species indicate different levels of water quality. Some species are more tolerant of pollution, while others will not live where there is any pollution. One method for determining the presence of macroinvertebrate species is to place a basket of rocks in the waterbody and leave it there for a certain period of time. When the basket is hauled up, the macroinvertebrates that have colonized it can be analyzed. Simple observations of macroinvertebrate presences can also be used to assess water quality. Thus, it is easy for citizens to become involved in ecological monitoring for local water bodies.
See the Maine guidelines for macroinvertebrate testing here.
Mayfly larvae, an indicator species that is intolerant of pollution.
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Benthic Macroinvertebrate Testing
