We often think of bacteria as disease causing microorganisms. Yes, there is definitely danger from falling sick due to these tiny fellas. But at the same it’s important to remember that many bacteria perform essential functions in nature, such as decomposition, carbon cycling, and nitrogen cycling.

We didn’t have the equipment necessary for testing microorganisms to determine the water quality so we looked for aquatic macroinvertebrates instead. Since macroinvertebrates live in the water all their life, their survival is directly related to the water quality and can tell us much without having to look too hard.

The term macroinvertebrate describes those animals that have no backbone and can be seen with the naked eye. They include insects, crustaceans, molluscs, arachnids and annelids. So yes, they can be rather big (such as the freshwater crayfish) although most are small.

Since most macroinvertebrates are very small, they are extremely sensitive to different chemical and physical conditions. If there is a change in the water quality due to pollutants entering the water, or a change in the flow downstream, then the macroinvertebrate community may also change. Therefore, the richness of macroinvertebrate community composition in a waterbody can be used to provide an estimate of waterbody health.

Different waterbodies have different compositions so it is important to know what your local characteristic community is like when determining the health of the waters. As a rule of thumb, too much of one macroinvertebrate is definitely not good. Diversity is key.

Water monitoring is easy and can be done as a family or group activity. Since water (and its quality) is essential for life- take some time to get to know the water that flows into your homes. We can all make a difference!