From ReefPedia

Category:Inverts

[edit] Pods Order: Calanoida Cyclopoida Gelyelloida Harpacticoida Misophrioida Monstrilloida Mormonilloida Platycopioida Poecilostomatoida Siphonostomatoida

Pods on the glass.

Ecology

Planktonic copepods are important to global ecology and the carbon cycle; They are usually the dominant members of the zooplankton, and are major food organisms for small fish, whales, seabirds and other crustaceans such as krill in the ocean and in fresh water. Some scientists say they form the largest animal biomass on earth. They compete for this title with Antarctic krill (Euphausia superba).

Because of their smaller size and relatively faster growth rates, however, and because they are more evenly distributed throughout more of the world's oceans, copepods almost certainly contribute far more to the secondary productivity of the world's oceans, and to the global ocean carbon sink than krill, and perhaps than all other groups of organisms together. The surface layers of the oceans are currently believed to be the world's largest carbon sink, absorbing about 2 billion tonnes of carbon a year, the equivalent to perhaps a third of human carbon emissions, thus reducing their impact. Many planktonic copepods feed near the surface at night, then sink into deeper water during the day to avoid visual predators. Their moulted exoskeletons, faecal pellets and respiration at depth all bring carbon to the deep sea.

Biology

Free-living copepods will be found only by towing very fine nets, certainly less than quarter-millimetre mesh, through a pond or sea-water, or by washing the fauna off marine algae through a net of this kind. Animals which may appear only as a tiny speck to the naked eye may be copepods but their identity demands most detailed microscopic examination of preserved specimens.

Being so small, free-living copepods can feed only on small food items like bacteria, diatoms or other unicellular forms. Eggs produced by the female copepod are carried in clusters in one or a pair of egg-sacs attached to the base of the abdomen. Females like this are easy to recognise as copepods.

Diet

Copepods eat bacteria, diatoms, and other tiny, single-celled organisms in the water. Maxillae, maxillipeds and antennae push food towards the mandibles (jaws), which process the food.

Predators

Free-swimming copepods are a component of zooplankton and are eaten by many organisms, including mussels, fish and fish larvae, squid, sea birds, and mammals (like baleen whales and some seals).

Reproduction

The female copepod produces clusters of eggs that she carries in one or two egg sacs that are attached to her adbdomen.