Overview
Octopus, squid, cuttlefish and the chambered nautilus belong
to the class cephalopods, which most scientists called “head
foot”. Cephalopods are mollusks and are related to bevalves
(scallops, oysters, clams), gastropods (snails and slugs), scaphopoda
(tusk shells) and polyplacophorans (chitons). Cephalopods have
well developed senses and large brains, and are thought to be
the most intelligent of all invertebrates. They can be found
in oceans around the world, from the warm waters of the tropics
to the near freezing water at the poles. They are found in the
wave-swept inter-tidal zone through to the cold, dark abyss,
and are still abundant in comparison with other endangered marine
species.
Cephalopods reach the largest size of any invertebrates. The
giant squid, or Architeuthis, which lives in the North Atlantic
is 17m (56 ft) long and weighs about 3 tons. This length includes
the tentacles, which may measure up to 6m (20 ft).
Scientists estimate that there are about 375 species of squid
in the world. But in some areas, like those along the east cost
of the Americas, only three species are found. The first one
is Loligo pealei, which lives between Cape Cod and Venezuela.
Loligo brevis can be found from Maryland to Argentina. And IIIex
illecebrosus, which is harvested along the continental shelf
from northern Newfoundland to the north coast of South America.
Although there are about a hundred species of squid, only four
species are caught commercially by the US. California or Monterey
squid (Loligo opalescens), the smallest catch, is harvested
in the Pacific. Longfin (L.peali) and shortfin (Illex illecebrousus)
are harvested in the Atlantic. Longfin squid is also called
Boston, or winter squid, while shortfin is known as summer squid.
Most squid are caught during the breeding season, when millions
gather to spawn. Giant squid is imported and sold as tenderized,
frozen steaks.
In the past 10 years, squid have become
increasingly popular. Consumers like the sweet taste, lack
of bones and odor. Their nervous systems are also useful -
the nerve fibers of North American giant squid have long been
used by scientists to study Alzheimer’s and other diseases.
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