Macrocyclops albidus
Copyright, Max-Planck-Institut fur Limnologie
Copepods are tiny
crustaceans,
so they are cousins of crayfish and water fleas. You can see
them with your eyes, but they don't get much bigger than 2
millimeters. There are many species of copepods that live in
our freshwater ponds, marshes,
and streams; all the pictures on this page are of the
species Macrocyclops albidus. Macrocyclops
albidus is one of our most common species. Copepods live just about
everywhere there is fresh water, including damp soil and
ditches. Macrocyclops albidus lives near the surface
or in shallow water with lots of plants, but they also
sometimes hang out on the bottom. Department of
Evolutionary Ecology, Max Planck Society Copyright, Dr. Ralf
Wagner Like their crustacean
cousins, copepods have two main body parts: cephalothorax
and abdomen.
They have ten legs, which they use for swimming. The abdomen
is like a rudder and helps the copepod steer. Macrocyclops
albidus and other copepods eat other tiny
plankton
organisms,
including: bacteria,
protozoans,
(amoeba, paramecium, euglena, etc.), tiny insect
larvae
(including mosquitoes), and other crustaceans. They will
even eat other copepods! Copepods also eat tiny bits of
plant and animal matter
floating in the current. Sometimes they attack the
fins
of fry
(baby fish) or
other small fish. When there are large numbers of copepods,
they can even kill fish. Female copepods are much
larger than males. After mating, the females carry clusters
of eggs, called "ovisacs." Eggs can take anywhere from 12
hours to 5 days to hatch. Department of
Evolutionary Ecology, Max Planck Society Department of
Evolutionary Ecology, Max Planck Society
