Copepods (From Gazette & Herald)

Copepods

ALTHOUGH never bigger than a grain of rice, often only pin-head size, the copepod is a most significant sea-dweller.

Because of two appendages on its head that wave like oars, the tiny crustacean is referred to as oar-footed but it is, in fact, an incompetent swimmer, going up and down in the water to take advantage of currents for lateral movement.

When female copepods are in profusion the sea turns red.

Trawlers seeking herring use a plankton indicator, a tube with a filtering disc of gauze. When the trawled disc goes red this indicates that copepods are present. The herring shoals will follow.

Consumed by sharks, whales, pilchards, mackerel and particularly herring, the copepod is the beginning of a food chain. Eating minute ocean plants, the creature itself is then eaten by herring which, in turn, are eaten by seabirds. The resultant bird droppings (guano) fertilise the crops on which sheep and cattle feed.

If ever there is a shortage of lamb chops and sirloin no blame attaches to the copepod. There are more copepods in the world than all the rest of creatures, including insects, put together. And every copepod strives to maintain a life cycle of ten days.

Updated: 14:31 Thursday, February 08, 2001