- Aquatic macroinvertebrates are an important part of
the food chain found in and around a body of water.
Aquatic macroinvertebrates are a link in the aquatic food
chain. In most streams, the energy stored by plants is available to animal
life either in the form of leaves that fall in the water or in the form
of algae that grows on the stream bottom. The algae and leaves are eaten
by macroinvertebrates. The macroinvertebrates are a source of energy for
larger animals such as fish, which in turn, are a source of energy for
other animals and even man.
- Aquatic macroinvertebrates differ in their sensitivity
to water pollution.
Some aquatic macroinvertebrates cannot survive in polluted
water. Others can survive or even thrive in polluted water. In a healthy
stream, the macroinvertebrate community will include a variety of
pollution-sensitive macroinvertebrates. In an unhealthy stream, there may
be only a few types of non-sensitve macroinvertebrates present.
- Aquatic macroinvertebrates provide information about
the quality of a stream over long periods of time.
It may be difficult to identify stream pollution with water
analysis such as pH and dissolved oxygen which can only provide information
at the time of sampling. Even the presence of fish may not provide information
about a pollution problem because fish can move away to avoid polluted
water and then return when conditions improve. However, most aquatic macroinvertebrates
cannot move to avoid pollution. A macroinvertebrate sample may provide
information about pollution that is not present at the time of sample collection.
- Aquatic macroinvertebrates are relatively easy to
Useful aquatic macroinvertebrate data is easy to collect
without expensive equipment. The data obtained by taking a macroinvertebrate
survey can serve to indicate the need for additional data collection on