About this key
This key covers the aquatic macroinvertebrates that can be found in the rivers and streams of North Dakota. This website focuses on the non-insect macroinvertebrates and has a companion site that covers the aquatic insects of North Dakota rivers and streams. The companion website can be found at www.waterbugkey.vcsu.edu. There are several links within this key that will take you there including the one in the left margin titled Aquatic Insects Key.
This website is primarily meant to be used by students, citizen groups, and professionals. It will be useful for those who want to implement a biomonitoring program as well as those who are just interested in what little creatures live in our aquatic habitats. Keep in mind these keys are for a specific geographical area and probably aren't suitable for general use in other areas.
What are Aquatic Macroinvertebrates?
Aquatic macroinvertebrates include such things as aquatic insects, snails, clams, and leeches. They are creatures without backbones that live in our rivers, lakes, streams, and ponds. The majority of macroinvertebrates you will find in a water body are insects. This is not surprising since it is estimated that 95% of all animal species are insects. This particular key, however, focuses on the non-insect aquatic macroinvertebrates. For an aquatic insect key go to our companion website mentioned above.
This website includes many different groups such as snails, daphnia, crayfish, leeches, and oligochaetes. For some of the groups we go all the way down to species level. Other groups may only go down to the Order or Family level. A couple we leave at the Phylum level (the sponges and flatworms). Hopefully you will find it useful.
What is Biomonitoring?
Biomonitoring is the cataloging of which organisms live in a particular habitat and then, from knowledge of what conditions those organisms tolerate, determining the well being of that particular habitat. For river systems, the biomonitoring of aquatic invertebrates, such as insects, is recognized as an important tool for determining a rivers health and, with proper background data, identifying changes in that health. For instance, if you go to a portion of the river and the main organisms collected are leeches, bloodworms, and certain types of snails, the water quality in that area is very poor. If, on the other hand you collect a lot of mayfly larvae, stonefly larvae, and caddisfly larvae, these are usually indicators of very good water quality. If you continue this sampling over long periods of time you can document changes that indicate changes in water quality.
Need help navigating our site? Click here for information on the features of this site. Otherwise, proceed with the buttons on the left margin or the links below.
This web site is funded by Region VIII EPA Section 319 funds administered by the North Dakota Department of Health.
Click here for a list of publications we have used in our lab for aquatic insect identification and for preparing this website.