There are many small arthropods that we have seen in the wetlands. Scuds, Daphnia (water fleas), and copepods are some examples of these. At different times of the year all of these arthropods have been seen in all of the areas of the wetlands.

Scuds are arthropods which are often confused with isopods. The difference between these two is that the scud is higher than it is wide and it is laterally flattened. A good way to determine that the arthropod you are looking at is a scud is to look at their swimming technique. Scuds swim rapidly and on their sides.

Copepods are another kind of arthropod that has been spotted in the wetlands. These are the most abundant winter zooplankton. Copepods grow slowly yet they do not stay as small as Daphnia are. You can identify a copepod by looking for a cylindrical body which is wider at the head end and long, trailing antennae and what are called “tail streamers”. Many of these are colored bright red and many carry eggs attached.

Daphnia (Daphnia pulex) have been the most common arthropod that we have seen. All of the water samples we have collect contained many Daphnia and usually in large numbers. Daphnia move in a distinctive way that is very jerky. You can also determine if what you are looking at is a Daphnia by looking at the body. Daphnia have a carapace with definite and prominent eyes. The carapace often develops a larger "helmet" and tail spike in summer to protect the daphnia from predators. This is either a seasonal or an inducible defense which is triggered by the presence of predators. The female carries eggs and developing young within the carapace. Daphnia can live up to 100 days. Daphnia swim with five legs that move water toward the mouth, filtering out food.