Fishing industry is an important economic activity that provides food and jobs for millions of people. The fishing industry includes all the activities involved in the commercial and recreational capture of fish and shellfish. The catching, processing, marketing, and conservation of fish and shellfish are all parts of the industry. The industry also provides various other products from the sea, such as seaweeds.
Fish are an excellent source of protein, one of the chief nutrients (nourishing substances) that people need for a good diet. As the world’s population has grown, so has the demand for food—especially food rich in protein. The fishing industry has increased its annual catch to help meet this demand. The industry markets food fish in a variety of forms. The fish are sold fresh, canned, cured, or frozen. In addition, about a third of the world’s fish catch is used to produce high-quality animal feed and various industrial products.
The oceans are by far the main source of fish. Only a small portion of the world’s commercial fish catch comes from such inland waters as lakes and rivers. Much of the inland water catch comes from aquaculture (fish farming). Fish farms are enclosures built on land, or areas in natural bodies of water, where fish and shellfish are raised for food. Fish farms may be inland or off ocean shores.
The fishing industry catches many kinds of fish. Such fish as anchovies, capelin, herring, mackerel, sardines, salmon, and tuna are caught near the surface of oceans and seas. Such fish as cod, flounder, hake, and pollock are harvested near the ocean floor. Freshwater fish, such as carp, catfish, and whitefish, are caught in inland waters or raised on fish farms.
The worldwide annual fish catch totals about 230 million tons (210 million metric tons). China is, by far, the leading fishing nation. The country accounts for approximately one-third of the world’s total fish catch. Other leading countries include India, Indonesia, Japan, Peru, Russia, the United States, and Vietnam.
The fishing industry employs millions of people worldwide. Many people work on oceangoing fishing boats, coastal craft, or small boats. Other areas of the fishing industry include the processing, packaging, and distribution of fish products. People who work in these areas of the industry perform such tasks as purchasing fish, filleting fish, shucking (opening and cutting) oysters, operating canning machines, and inspecting fish markets to enforce pure-food laws.
People have fished for thousands of years. Through the centuries, they have used hooks, spears, nets, and traps to capture fish. People still use such equipment, but commercial fishing crews now harvest most of their catch with huge nets. In addition, modern fishing vessels have various devices that make fishing more efficient. For example, advanced navigational aids and fish-finding equipment enable fishing crews to range far from their home ports and to pinpoint schools of fish. Refrigeration systems aboard the vessels help keep the catch fresh during long voyages at sea.
During the mid-1900’s, many countries expanded their fishing fleets. These fleets increased their fish catch along their home coasts as well as in distant waters. As a result, the fish harvest generally increased each year. But at the same time, overfishing severely reduced stocks in some fishing areas. Disputes also arose among countries over the ownership of fish resources. Traditionally, fish have been considered common property—that is, no one owned them until they were caught. The fish then became the property of whoever caught them. After the development of long-range fishing fleets, many nations wanted to protect the fish resources along their coasts from fleets of other countries. As a result, a number of international commissions were formed to promote fish conservation and to help settle disputes over fishing rights.
During the 1970’s, almost all nations bordering the sea established fishery conservation zones, also known as exclusive economic zones, in further efforts to conserve and protect their fish resources. These zones extend 200 nautical miles from a nation’s coast. A nautical mile equals 1.15 statute miles, or 1.85 kilometers. Countries that have adopted such zones claim authority over all fishing—and ownership of all fish and other natural resources—within the zones.
Where fish are caught
Areas where fish are caught commercially or recreationally are called fisheries. In many cases, fishing crews harvest more than one species of fish from a particular fishery. A fishery may be a small lake. Or it may extend across an enormous section of an ocean. For example, the tuna fishery that lies off the west coast of Central and South America covers about 5 million square miles (13 million square kilometers).
Ocean fisheries
provide about three-fourths of the world’s commercial fish catch. This figure includes the production from marine fish farms. Almost all the ocean catch comes from waters near seacoasts, especially the shallow waters over the continental shelf. The continental shelf consists of submerged land along the coasts of the continents. In some places, the shelf extends great distances out into the sea.
Many of the fish caught in waters over the continental shelf are taken from regions of upwelling. Upwelling occurs during certain seasons when winds blow surface waters near the coast offshore. The colder bottom waters, which are rich in nutrients, then rise to the surface near the coast. This upwelling provides nutrients for the growth of tiny organisms that fish feed on, thus promoting growth of the fish population. Upwelling takes place chiefly along the coasts of Peru, western North America, northwest and southwest Africa, Somalia, the Arabian Peninsula, and Antarctica.
Atlantic Ocean fisheries.
About 10 percent of the world’s annual fish catch comes from the Atlantic Ocean. The northern Atlantic is the most productive area. The coast of North America from Newfoundland and Labrador to New England is an important fishing area. Leading fishing catches in this region include cod, flounder, herring, lobsters, and scallops. The Gulf of Mexico, an arm of the Atlantic Ocean, is a productive area for the United States fishing industry. It supports the nation’s main menhaden fishery. The Gulf of Mexico also provides large quantities of crabs, lobsters, and shrimp.
The Atlantic Ocean has several other rich fishing areas. They include the northeast Atlantic near Iceland and the United Kingdom and the southwest Atlantic near Argentina and Brazil. Crews from a number of nations—including Denmark, Iceland, Norway, Russia, and the United Kingdom—fish the waters of the northeast Atlantic. They catch herring, capelin, mackerel, sand lances, and many other types of fish. The major catches in the southwest Atlantic include hake, squid, and whiting.
Pacific Ocean fisheries.
About 50 percent of the world’s fish catch comes from the Pacific Ocean. The northern Pacific is the most productive fishing area. The chief fish caught in the Bering Sea, the Gulf of Alaska, and other areas of the northern Pacific include anchovies, mackerel, and pollock. Salmon are also an important catch. Leading shellfish harvested from the northern Pacific include crabs, oysters, and scallops.
Other important fisheries of the Pacific Ocean include the waters of the southeast Pacific off the coast of South America and the coastal seas of the western Pacific from Indonesia to Japan. The chief fish caught in the waters off the west coast of South America include anchovetas and jack mackerel. The leading fishing countries in this area are Peru and Chile. Important catches in the western Pacific include mackerel, scad, and tuna. China, Indonesia, Japan, the Philippines, and Vietnam are the leading fishing countries of this area.
Indian Ocean fisheries.
About 5 percent of the world’s fish catch comes from the Indian Ocean. Leading catches in the Indian Ocean include croakers, shad, tuna, and shrimp. The leading fishing countries of this region are Bangladesh, India, Indonesia, Myanmar, and Thailand.
Inland fisheries.
About 30 percent of the commercial catch worldwide is harvested yearly from ponds, lakes, rivers, streams, and fish farms in inland waters. China and India lead all other countries in the fish catch from inland waters. China’s annual inland-water catch accounts for about 50 percent of the world total, and India’s is about 10 percent of the total. Both countries chiefly harvest carp, tilapia, and other plant-eating fish. Other leading inland-water fishing countries include Bangladesh, Brazil, Cambodia, Egypt, Indonesia, Myanmar, and Vietnam.
The major freshwater fisheries of the United States include the inland waters of the Southern States and the Great Lakes. The inland waters of the South are fished for buffalo fish, carp, catfish, and crayfish. The Great Lakes are fished chiefly for carp, chub, smelt, whitefish, and yellow perch.
The primary fish caught in Canada’s inland waters include smelt, trout, walleye, whitefish, and yellow perch. The Great Lakes are the center of the freshwater fishing industry in Canada.
Fish farms.
Each year, the world’s fish farms produce more than 120 million tons (100 million metric tons) of fish, shellfish, and aquatic plants (plants that live in water).
Fish farms range from simple ponds or flooded rice fields to highly engineered hatcheries in which the environment is almost completely controlled. Fish farmers try to eliminate pollutants and other harmful environmental conditions so that fish can flourish. However, production can be severely affected by the spread of an infectious disease. Farmers provide fish with proper nutrients and protect them from animals that prey on them. Aquaculture is commonly used to rebuild salmon and trout stocks that have been severely reduced.
The main fish raised on fish farms throughout the world include carp, catfish, salmon, tilapia, and trout. China leads all countries in aquaculture production. In terms of quantity produced, China harvests over half of the world total. Other leading aquaculture countries include Bangladesh, Chile, Egypt, India, Indonesia, Japan, Norway, the Philippines, South Korea, and Vietnam. The main fish and shellfish raised on fish farms in the United States include catfish, clams, crayfish, oysters, salmon, and trout.
How fish are caught
Fishing vessels vary greatly in size and in the number of crew members they carry. Vessels in coastal fishing fleets are 25 to 130 feet (8 to 40 meters) long. Their crews consist of as many as 20 to 25 people or as few as 1 or 2, depending on the fishing method being used. Coastal vessels can remain at sea for several days or weeks. The ships store their fish catch in holds chilled either by ice or by refrigeration systems.
Long-range fishing fleets stay at sea for months at a time and travel great distances from their home ports. Many modern fleets include processing-catcher vessels, as well as processors, refrigerated transporters, and supply ships. Processing-catcher vessels, which measure about 260 feet (80 meters) in length, both catch fish and process the harvest into various products. Their crews have from 50 to 100 members and in most cases include a number of women. Many processing-catcher vessels can process and freeze more than 100 tons (90 metric tons) of fish daily.
Fishing crews use a variety of gear to catch fish. The equipment used depends on the behavior of the fish being sought and the nature of the fishing area. The chief types of gear include (1) nets, (2) hooks, (3) traps, and (4) harpoons.
Nets.
Most of the world’s commercial fish catch is taken by huge nets. There are three main types of nets: (1) seines, (2) trawls, and (3) gill nets.
Seines.
Seines << saynz >> account for more than a third of the world’s fish catch. Fishing crews use seines chiefly to catch anchovies, capelin, herring, mackerel, menhaden, sardines, tuna, and other pelagic, schooling fish. Pelagic fish swim in the open ocean, sometimes near the surface of the water.
The most widely used seine is the rectangular purse seine. Purse seines range from about 660 to 6,600 feet (200 to 2,000 meters) long. They have floats along the top and weights and rings along the bottom edge. A rope or cable called a purse line runs through the rings.
A purse seine is set into the water from a large vessel called a seiner with the aid of a small, high-powered boat called a skiff. After the crew spots a school of fish, they launch the skiff from the seiner with one end of the net attached. The seiner speeds ahead, encircling the school and playing out the net as it goes. The bottom of the seine is then closed off with the purse line, capturing the school. Seiners vary from about 30 to 230 feet (10 to 70 meters) in length and carry 12 to 20 people.
Trawls
are funnel-shaped nets that are closed off at the tail end, where the fish collect, and open at the mouth. The most commonly used trawl is the otter trawl. The net has floats along the top edge of the mouth and weights on the bottom edge. The net is attached by two long towing cables to the back of a vessel called a stern trawler or trawler. A large doorlike otter board is attached to each towing cable near the open end of the net. As the trawler tows the net, the water forces the otter boards to spread apart, holding the net open to capture the fish. The mouths of otter trawls used in midwater can spread out to a width of about 300 feet (90 meters). Those used on the ocean bottom spread to a width of about 120 feet (37 meters).
Trawls catch cod, flounder, hake, pollock, red snapper, scallops, shrimp, and other fish and shellfish that live on or near the ocean floor. Most trawling is done over the continental shelf in waters less than 660 feet (200 meters) deep. But some stern trawlers fish in waters as deep as 3,300 feet (1,000 meters). Trawlers use sonar and other equipment to locate concentrations of fish (see Sonar). A small trawler needs a crew of at least four members. Most trawlers more than 150 feet (45 meters) long carry processing equipment and require larger crews.
Trawling accounts for about a third of the world’s fish harvest. The otter trawl is the primary fishing gear of distant-water fleets of European and Asian nations that harvest fish from the ocean bottom.
Gill nets
are long rectangular nets with floats on top and weights on the bottom. They range from 50 to 1,200 feet (15 to 370 meters) in length. The nets hang in the water near the surface or close to the ocean floor. A gill net is made of thin twine and is nearly invisible in the water. The net hangs in the path of migrating fish and forms a wall of webbing that entangles the fish. The open spaces of a gill net allow fish to thrust only their heads into the net. The fish try to swim through the net, thrashing about and becoming more entangled.
Gill nets catch billfish, herring, salmon, sharks, and bottom fish. However, all these fish can be caught with other types of gear. As a result, the total catch with gill nets is less than 5 percent of the world harvest. Most vessels equipped with gill nets are less than 50 feet (15 meters) long and have crews of one or two.
Drift nets are long gill nets of nylon webbing. They are used mainly in open waters by distant-water fleets. A single net measures about 3 nautical miles long. One vessel can set out 8 to 10 drift nets, stretching a total of about 30 nautical miles. Fishing crews set out drift nets at night and pull them in during the day. The nets catch billfish, salmon, and tuna.
Drift nets accidentally catch animals besides the target fish. They often entangle dolphins, marine birds, seals, turtles, and whales. In addition, large drift-net fisheries in the open ocean create hazards to ships whose propellers can become tangled in the nets. Fishing groups and environmental organizations have called for a halt to drift-net fishing. In 1989, the United Nations (UN) passed a resolution banning the use of drift nets in the South Pacific after June 1991. In November 1991, the UN passed a moratorium (temporary halt) on drift nets in international waters (bodies of water that lie outside the authority of any nation). The moratorium, which took effect on Jan. 1, 1993, banned the use of all drift nets at least 11/2 nautical miles long in international waters. Most nations have complied with the moratorium.
Hooks
take advantage of the feeding behavior of fish. Bait or lures attached to a hook tempt fish to bite the hook. Hooks account for only a small percentage of the world’s fish catch. The most common hooking methods used by commercial fishing crews are (1) bait fishing, (2) trolling, and (3) long-lining.
Bait fishing.
In bait fishing, after the crew sights a school of fish, they throw live bait or ground-up fish into the water from the boat. The bait attracts schools of tuna or other species that feed on smaller fish to the surface near the boat. As the fish feed excitedly on the bait, the crew uses poles with bare hooks to haul them in. Most bait boats have a walkway around the stern from which a crew of as many as 20 people pull in the fish.
Trolling
involves towing as many as six fishing lines from two long poles. One pole extends from each side of a vessel. In many cases, metal flashers or feather lures attached to the lines attract fish. A large fleet of trolling vessels, called trollers, fishes for albacore and salmon off the coasts of British Columbia and the western United States. Billfish and tuna are also caught by trolling. Most trollers have crews of only two people.
Long-lining
involves using a long main line with attached short dropper lines. The main line may be stretched across the water’s surface to catch such pelagic fish as billfish, sharks, and tuna, or near the ocean floor to catch such bottom fish as cod and halibut. Thousands of dropper lines with baited hooks may hang from the main line. Pelagic long-lines may be as long as 60 nautical miles. Bottom lines are much shorter. A small long-line vessel needs a crew of only 3 or 4 members. Large Japanese tuna vessels carry crews of 20 to 45.
Traps
depend on the migratory or feeding habits of fish. Most traps contain bait to attract fish. Only a small fraction of the worldwide fish harvest is taken by means of traps. A fish trap has an entry consisting of a funnel-like tunnel or ramp. This entry directs fish through a small opening in the side of the trap. Once inside the trap, the fish have little chance of escaping.
Small, baited, boxlike traps capture chiefly shellfish, such as crabs and lobsters. These traps lie on the bottom of the ocean or a lake or stream and are tethered to a buoy on the surface. Larger, stationary traps float near shore in the path of migrating fish. These traps are anchored in place or fastened to wooden pilings driven into the seabed. They have been used mainly to catch herring and salmon but are not often used today.
Harpoons
are barbed spears connected by a line to a vessel or large float. They may be shot from a cannon or hurled by a crew member. Harpoons have been used mainly to harvest whales and large game fish that swim near the ocean surface, such as swordfish and marlin. For more information on whaling, see Whale (Whaling).
How fish are processed and marketed
Methods of processing.
The quality of fish declines rapidly after they die. Bacteria that can cause spoilage immediately begin to attack the fish, and enzymes start to break down the protein in fish tissues. As a result, a number of processing methods have been developed through the years to prolong the freshness of fish.
Drying, salt curing, and smoking
have been used to process fish for thousands of years. All three methods reduce the moisture content of fish and thus slow the growth of bacteria and the breakdown of protein.
Drying fish in the open air for six weeks or more removes most of the water from them. Drying is generally used along with salt curing or smoking.
In salt curing, processors first cut open the fish and remove the head and backbone. They then cover the fish with salt, which draws out the moisture and produces a salty solution called brine. Next, the fish are dry-salted or pickled. In dry-salting, workers drain off the brine and hang the fish up to dry. In pickling, the fish are stored in the brine.
To smoke fish, processors first cut up the fish and soak them in brine. They then place the fish in a large oven, where smoke and heat from smoldering wood chips dries the fish. Processors use this method chiefly to improve the flavor of fish.
Canning
involves sealing cut-up fish in metal or glass containers and then cooking the contents under pressure. The high temperature and pressure kill bacteria and halt protein breakdown.
Freezing
also prevents the growth of bacteria and protein breakdown. The quickly frozen fish are packaged in airtight wrappers or covered with a thin layer of ice. They are stored at –20 °F (–29 °C) or lower. Much of the catch of such fish as cod and flounder is filleted (deboned) and frozen. Often, the individual fillets are frozen together in large blocks of fish. These blocks may then be made into fish sticks and meal-sized portions of breaded fish.
Fish may be minced and blended before freezing to make surimi, a fish paste with a high protein content. In Japan, surimi is used mainly to make fish cakes. Surimi is used in other countries to make imitation shellfish products, including imitation crab legs and shrimp.
Other processing methods
are used to produce meal and oil from fish. These industrial products are made from such species as anchovies, capelin, herring, menhaden, and sardines, and from scraps left over after filleting. To produce fish meal and fish oil, processors first cook the fish with steam. They then squeeze out most of the water and oil. The remaining material, a high-protein meal, is then dried. Fish oil is obtained by separating the oil from the water in a whirling device called a centrifuge.
Feed companies add fish meal to livestock feed and dry pet food. Hatchery managers also feed the meal to trout and salmon raised in hatcheries. Manufacturers use fish oil to make a number of products, including glue, paint, lubricants, and ink.
Marketing.
Fresh fish may be sold daily in fishing ports near fishing areas. However, fish and fish products to be sold in distant markets must first be processed to prevent spoilage.
Most fish processors operate in fishing ports. Many fishing crews sell their catches to processors at set prices or at auctions after fishing trips. The price a catch brings at auction depends on the supply of fish at the market and the demand for it. A fishing crew may not know in advance what a harvest will earn—if it sells at all. The uncertainty of the auction market has led some fishing crews to form marketing cooperatives, groups that collect the catch of their members and sell it to processors. Cooperatives enable their members to know, before they leave port, how much fish to catch and how much the harvest will earn. Processors place orders with the cooperative for a specific quantity of fish before a fishing trip. At the same time, both sides agree on the price to be paid for the catch.
Processors sell most of their fish products to fish brokers in large cities. The brokers, in turn, sell the products to restaurants and food stores.
Fishery conservation
The world demand for food continues to grow as the human population increases. The harvest of ocean fish continues to expand to meet world food demands. Overfishing has greatly reduced some fish stocks in many of the world’s fisheries. Although fish resources are considered renewable, scientists believe that the oceans can produce only a limited quantity of fish over time.
In addition to overfishing, bycatch poses a tremendous challenge to fishery conservation. Bycatch includes fish and other marine animals that are inadvertently captured along with target fish species. Often, such creatures cannot be captured legally in a particular fishery or cannot be marketed. Some animals caught as bycatch are returned to the sea alive, but many die and are discarded. Bycatch occurs in practically all fisheries. It cannot be avoided because most fishing areas are inhabited by a variety of fish and other marine animals, and fishing gear is not selective enough to capture only the target species. Scientists estimate that about 25 percent of the world commercial fish harvest is discarded as bycatch.
Government regulation.
Most major fishing nations have laws to conserve and protect their fish resources. Almost all nations that border the sea have established authority over fishery conservation zones extending 200 nautical miles from their shores. These zones are intended to protect the nations’ coastal fishing industries by controlling the harvest by fleets from other countries. Nations may also pass conservation laws to manage and safeguard marine life in local coastal fisheries.
Many regulations try to curb the impact of fishing and its associated bycatch on the overall ecology of fisheries. Some regulations set quotas that limit the total catch of certain species in a fishery and in a few cases limit the number of fishing vessels permitted in an area. Others restrict the areas and the time of year in which crews may fish. The size and type of fishing gear that may be used in a fishery are also regulated.
Water pollution controls also aid in fishery conservation. Such controls limit the amount of harmful materials that may be released into inland and coastal waters. These materials can kill fish or the plants and animals on which fish feed.
International commissions and treaties.
Through the years, fishing nations have agreed to work together in managing fishery resources in international waters. A number of commissions have been established to protect a particular species of fish or all species in a certain area. For example, the International Pacific Halibut Commission helps regulate halibut fishing off the west coasts of Canada and the United States. The International Council for the Exploration of the Sea promotes the conservation of all fish species in the North Atlantic Ocean.
Most international commissions devoted to fishery conservation operate in a similar manner. Scientists from the member nations or from the organization itself gather statistics on the size of the catch and conduct other research regarding a particular fishery or species of fish. The commissions meet annually to review the results of these studies and to recommend ways of managing fishery resources. Each member nation then has the responsibility of passing and enforcing laws based on the recommendations.
Many nations also make bilateral treaties to manage fishery resources in international waters. Under such treaties, two nations agree to meet periodically to exchange information on fisheries of interest to both countries and to discuss conservation measures.
National agencies and international commissions are developing codes of conduct for responsible fishing. These guidelines are designed to ensure that no fish population falls too low to maintain diversity of species in a fishery. The rules also take into account environmental factors that can affect stocks of various species.
Scientific research
involves many activities to improve fishery management. Researchers determine the maximum number or weight of fish that can be harvested annually without severely damaging the stock. Researchers often rely on records of the harvest from a fishery to check changes in the abundance of stocks from year to year. They also conduct fishery resource surveys. By analyzing information provided by such activities, they determine what quantity of a species can be harvested in a particular area. However, collapses of fish stocks often occur in spite of such determinations. Such collapses can occur because changing environmental conditions can affect the growth and survival of marine animals over short periods as well as long ones.
Scientists study the effects of the environment on changes in fish abundance and the effects of fishing on other species. Most fish feed on other fish. Dolphins, seals, and marine birds also prey on fish. Overfishing of prey species, such as anchovies, herring, and sardines, reduces the food supply of predator species. However, overfishing of predator species, such as cod, salmon, and tuna, increases the supply of prey species. Thus, scientists are working to develop management techniques that help conserve a fishery’s entire ecosystem—that is, all the living and nonliving things in the fishery and the relationships among them—rather than just an individual species. To help reduce bycatch, scientists study ways of modifying fishing gear to reduce the capture of nontarget species.
Some researchers work to increase the rates of survival and growth of fish. Such research especially helps fish farmers. Commercially raised fish have greatly increased fish production, chiefly in Asia and Europe. In addition, some researchers are studying unharvested types of fish to develop new products and markets. Such efforts seek to both increase the world’s food supply and promote fish conservation. Through the development of new fish resources, the world’s total catch can remain constant—or even be increased—without overfishing individual stocks.
