-moving waters with rocky substrate such as, riffles and runs of
streams and rivers; Slow-moving or still
waters with soft substrate and vegetation, such as pools and backwater areas of streams and rivers;
wetlands and ponds.

Size range

Aquatic invertebrates have typical size ranges, which can vary according to the conditions (chemcal and
physical stability of the aquatic environment) and the availability of food.  The ranges in (mm) are shown below: 


Stress tolerance is the organism’s ability to withstand a certain amount of anthropogenic influences.  The index range for each category is based upon a (0-10) scale, which is based mostly on the ability to withstand varying levels of dissolved oxygen and other chemical and physical disturbances.  In some cases tolerance values are undetermined (U). 


In the organisms describtion the scale will be depicted as follows:

Size range, Tolerance and Habitat - Example: S-M (L)(F), which shows an organism ranging in size from small (S) to medium (M), has a low tolerance (L) and lives is fast (F) aqautic environments.