Aquatic macroinvertebrates are small animals that live in water, are big enough to see with the naked eye, and have no
backbone. These animals include many types of insects as well as other animals such as worms, mollusks, and
crustaceans.
Most aquatic macroinvertebrates make their homes in rocks, leaves, and the sediment of streambeds. These organisms
have many special adaptations allowing them to live in demanding environments.
Macroinvertebrates that live in riffles and fast-moving water may have features that help them hold on to rocky or hard
substrates such as hooked feet or suction cups; or flat, streamlined bodies that can handle rapid water velocities.
These bugs are important because they are an integral part of the food chain. They provide food for fish and other
aquatic organisms.
Many of them are also key indicator species. They can tell us about the quality of the water where they are found. Bugs
that have a low tolerance to pollution tell us that the water they are found in is relatively healthy. If we do not find these
bugs, then it could possibly be due to some sort of pollutant or other impairment to the water body.