Commercial fishing is a worldwide enterprise that involves the capture
of marine and freshwater fish and shellfish and their preparation for market.
Fishing equipment ranges from small boats whose nets are cast and hauled in by
hand to factory ships equipped with the most advanced technologies for finding,
harvesting, and preparing huge amounts of fish. These large catches are very
costly, however, not only in the price of their equipment and fuel, but also in
the depletion of fishery resources their use brings about.
The major portion of the total fish harvest consists of few fish
species, which are divided into two primary groups. Pelagic species - those
which live in the near-surface layers of the oceans, this include several
species of herring, tuna, salmon, anchovies, pilchard, sardines, menhaden, and
mackerel. Demersal species - fish that live in the near-bottom layers of the
ocean, this includes cod, sole, halibut, haddock, hake, and flounder. Large
catches are also made of a group of fish classed commercially as SHELLFISH -
shrimp, lobster, scallops, oysters, clams, crabs, mussels, and squid. WHALING
was once a major part of the fishing industry. Overfishing has endangered many
whale numbers, however, and the field has lessened in importance.
Almost all large pelagic and demersal fish catches are made over or near
the continental shelf, the underwater plateau around the continents and large
islands. In these waters temperatures, water depths, and the currents that
influence the amounts of available food create an environment that is highly
favourable to the existence of large schools of fish.
The animals living in and on the bottom of the continental shelf serve
as additional food sources for demersal fish. Also, most species spawn on
continental shelves, and the main nursery grounds of many species are also in
coastal regions. The main fishing grounds are located on the wider continental
shelves of the mid and high latitudes. The single most important area is the
North Pacific, where as much as one-quarter of the world's fish catch is taken.
THE DEVELOPMENT OF THE FISHING INDUSTRY
Prehistoric people were hunters and food collectors, and they found much
of their food in lakes, rivers, and shallow coastal ocean waters. Shellfish were
the most accessible food , and the large shell heaps found around the first
fishing technique, the use of bare hands.
During 10,000-6000 BC, certain cultures that depended almost entirely
on a diet of fish developed primitive fishing technologies. The Scandinavian
Maglemosian culture used stone-pointed fishing spears, antler and bone harpoons
and fishhooks, and lines and nets woven of bark fiber. Improved equipment
increased the size of catches, and preservation techniques were developed for
drying, smoking, salting, and...