What do macroinvertebrates tell us

They often have adaptations that allow them to survive in water with low dissolved oxygen, turbid waters or nutrient-enriched waters.

If the stream was restored, we would hope to see more pollution-sensitive and tolerant macroinvertebrates living there. Every day, macroinvertebrates are surrounded by water and any pollutants that may be in the water.

If pollutants were in the water last week or yesterday, the quantity and diversity of macroinvertebrates present would reflect this in the water quality. Different types of macroinvertebrates have different requirements to survive.

Some require cooler temperatures, relatively high dissolved oxygen levels or certain habitats. Other macroinvertebrates may be able to survive in less-than-ideal conditions — where there are low dissolved oxygen levels or more sediment — or where the water temperature is warmer.

To become a volunteer stream monitor, contact Lily Whitesell at Official websites use. Share sensitive information only on official, secure websites. JavaScript appears to be disabled on this computer. Please click here to see any active alerts. They include dragonfly and stonefly larvae, snails, worms, and beetles. They lack a backbone, are visible without the aid of a microscope and are found in and around water bodies during some period of their lives.

Benthic macroinvertebrates are often found attached to rocks, vegetation, logs and sticks or burrowed into the bottom sand and sediments. Substrate - what the bottom of the stream is comprised of will affect the types of macroinvertebrates. For example, macroinvertebrates that eat tiny food particles prefer sandy or muddy substrate.

Nutrient enrichment - added nutrients from human sewage, fertilizer or manure can accelerate the growth of algae and other plants. When these plants die decomposition by microorganisms can use up dissolved oxygen in the water. Low pH can weaken shells and exoskeletons and kill macroinvertebrates. Removal of riparian vegetation - this takes away macroinvertebrates' food source and important breeding grounds.

They are indicators of water quality. Different types of macroinvertebrates tolerate different stream conditions and levels of pollution. Depending on the types of macroinvertebrates found in a stream, predictions about water quality can be made. For example, caddisflies, mayflies, and stoneflies can not live in polluted water.

If these bugs are found in a stream, the water quality there is probably good. However, that doesn't mean that if these bugs are not found in a stream the water quality is bad.