Coliform bacteria are normal resident bacteria found in the intestines of mammals. The presence of coliform in a body of water indicates that human or other animal wastes are present. Coliform bacteria are also an indicator that disease-producing pathogens may be present in the water. Clearly visible to the unaided eye, jellyfishes and comb jellies are the largest zooplankton. Some of these gelatinous creatures swim, though they are still at the mercy of the water currents.
Jellyfishes have tentacles with stinging cells used to stun prey.
The most famous jellyfish in the Chesapeake is the sea nettle. Sea nettles feed voraciously on zooplankton, including fish larvae, comb jellies and even small fish. Because of the large volume of water in their bodies, few animals except sea turtles prey on sea nettles. Comb jellies, lacking the stinging cells of nettles, capture prey with adhesive cells. They, too, consume vast quantities of small copepods and zooplankton, especially oyster larvae.