The term zooplankton is a single word that encompasses a whole host of
drift on Stellwagen Bank. Many, if not most, of the species on the Bank spend
some part of their life drifting on the tides, feeding and growing as plankton.
Zooplankton varies from tiny, shrimp-like crustaceans like copepods, hyperiids
and euphausids, to larval stages of gastropods, crustaceans and fish.
Some organisms are born, and spend their entire life as plankton, drifting along
with the currents and tides; these are the holoplankton. The meroplankton are
those organisms which start off as planktonic, but as they progress through
their life stages, become strong swimmers and drop out of the realm of plankton.
They generally rely on the phytoplankton (plant plankton) as their main source
of food, although some of the larger zooplankters feed on smaller organisms, or
the bacteria (microzooplankton) found in the water column.
Just over a few millimeters in length but
exceptionally abundant and diverse, copepods graze upon plant plankton
and are grazed upon by
almost everyone else - as animals that drift, they are considered part
of the zooplankton community.
Zooplankton is a major focus of research at CCS as they relate to the natural
history of the North Atlantic right whale. A long term habitat study of the
right whales looks at a variety of zooplankton species to piece together a story
of how right whales use Cape Cod Bay during late winter and early spring. Fifty
to sixty ton right whales are dependent upon a group of 'calanoid copepods' for
food; the copepods are dependent upon each other and phytoplankton for grazing;
phytoplankton depends upon the changing cycles of the sun, currents and
nutrients. The population of right whales is only as strong as any one of these
Martinez, A.J. (1994). Marine Life of the North Atlantic; Canada to New England.
Produced by Norman Katz
Newell, G.E. and Newell, R.C. (1979). Marine Plankton; A practical guide.