By Prof. Hasan Khan
The term fishery is used to describe the waters where fishing takes place or the species of fish being harvested.
Fisheries include familiar finned fish species, like cod and flounder; mollusks, including oysters and squid; and crustaceans, such as shrimp and crabs.
Lesser known fisheries include echinoderms, like sea urchins; some amphibians, including frogs; and coelenterates, such as jellyfish.
Even the harvest of whales is usually considered a fishery. Fisheries are an important source of food, income, jobs, and recreation for people around the world.
This is particularly true in island nations, such as Japan and Iceland, where seafood is eaten as a major source of protein. The average person in Iceland eats nearly 90 kg (200 lb) of fish per year, more than six times the worldwide average.
Worldwide harvest of fishery products has steadily increased to meet the growing global demand for seafood. In 1995, an estimated 113 million metric tonnes of fishery products were harvested. China was responsible for the largest harvest, followed by Peru, Chile, Japan, the United States, India and Russia.
The increasing demand for seafood has led to a complex, global system of trade in fisheries products. Japan is the largest importer, followed by the United States, France, Spain and Germany.
Thailand is the largest exporter, followed by the United States, Norway, China and Denmark. The United States imports large quantities of high-valued fishery products, such as shrimp and lobster.
Today scientists consider many fisheries to be fished beyond the capacity of the resource. Current harvest rates are not thought to be sustainable that is, able to be maintained year after year without depletion of the fish stock.
Experts believe that increases in world fish supply will require better management of the resources as well as the increased use of fish farming or aquaculture.
The range of fisheries is immense over 4000 aquatic species are harvested worldwide. The shrimp fishery alone includes well over 40 species. Fisheries are located almost anywhere there is water.
Over 80 per cent of the world’s fisheries are located in the coastal and ocean environment, and the remaining 20 per cent are found in inland freshwater fisheries. Currently, over half of the world’s fishery harvests come from the Pacific Ocean; 25 per cent are from the North Pacific alone.
The largest fisheries group is made up of small, pelagic (open ocean) fishes such as herring, sardine, anchovy, and related species.
Over 20 per cent of the world’s fishery harvest comes from this group, and Chile and Peru are the leading harvesters. These fish have relatively low commercial value and are often used to make feed for poultry, hogs, and other animals.
Another large category of harvested fishes, accounting for nearly 10 per cent of the world’s fishery harvest, is the groundfish, or demersal fish, that live near the ocean floor. These generally white-fleshed fishes include cod, haddock, pollock and hake. Cod and haddock tend to be relatively high in commercial value.
Fish such as tuna, swordfish, marlin, and mahimahi make up the large pelagic fish category and account for nearly 5 per cent of world harvest. Tuna is consumed fresh in great quantities in Japan and sold canned around the world. Canned tuna is the fish eaten most often in the United States.
Salmon belong to the anadromous group, meaning they lay their eggs in freshwater but usually spend their adult lives in the ocean. Although the salmon fishery only accounts for about 2 per cent of world fishery harvests, it is one of the most important wild fisheries in the United States (especially in Alaska), Canada, Japan and Russia.
Salmon are also cultured in farms in many countries including Norway, Chile, Canada, Scotland, Australia, and the United States. Some species of salmon are also highly prized sport fish.
Several freshwater fisheries are also important. Carp and related freshwater fish are consumed mostly in Asia and parts of Europe. Carp are generally raised in ponds and account for nearly 10 per cent of all fish harvested worldwide. In the Southern United States, the farm-raised catfish industry grew rapidly from a cottage industry in the 1970s to the largest aquaculture industry in the Unites States in the 1990s.
The tilapia, a freshwater or brackish water (mixture of fresh and saltwater) fish native to Africa, is now being raised globally to add protein to the diets of people in less-developed areas especially in Asia and South America.
It is also being sold to meet the growing demand for seafood in countries such as the United States. Tilapia harvests make up a relatively small percentage of the global fish supply, but production is still increasing.
Shrimp are harvested worldwide. Most large and medium-sized shrimp come from the tropical waters of countries like Thailand, India, Ecuador, and Mexico. Many small shrimp are harvested from the cold waters of Iceland, Greenland, and Canada.
Today, cultured or farmed marine shrimp play an important role in supplying the world’s shrimp demand. Total wild and farmed shrimp harvest accounts for less than 5 per cent of the total world fisheries harvest. Even so, shrimp has a very high commercial value and is the most important species group in world fisheries trade.
Fisheries in Pakistan
Fishery plays an important role in the national economy. It provides employment to about 300,000 fishermen directly. In addition, another 400,000 people are employed in ancillary industries. It is also a major source of export earning. In 1998-99, fish and fishery products valued at US $120 million were exported from Pakistan.
Federal government is responsible for fishery of exclusive economic zone of Pakistan. In addition, it is also responsible for making policies, inter-provincial co-ordination, planning, research, quality control, training, exploratory fishing, stock assessment, fisheries management, fleet improvement, data collection and export etc.
Pakistan is endowed with rich fishery potential. It is located in the northern part of the Arabian sea and has a coastline of about 1,120 km with a broad continental shelf and its exclusive economic zone extends up to 200 nautical miles from the coast.
There are about 16,000 fishing boats in coastal area of Pakistan which operate in shallow coastal waters as well as in offshore areas. There fishing boats undertake fishing trips lasting for few hours to about 25 days depending upon type of fishing. Total production from inland and marine waters is approximately 0.60 million tonnes.
Fisheries management
Fisheries are difficult to manage effectively because they exist in a complex ecosystem and are often considered a common property resource (owned by all citizens of a nation).
Aquaculture , or fish farming, in which aquatic organism are raised under controlled conditions in ponds, tanks, or floating net pens, is becoming a part of fisheries management. Aquaculture techniques, which help increase stock populations and control predators, are used in the oyster, clam, and mussel fisheries.
Fish farming may help reduce harvest pressure on the remaining wild stock. In Japan, the chum salmon fishery and several other fisheries depend upon hatcheries where fish reproduction and survival is enhanced to provide the young fish. In fact, aquaculture production is becoming an essential part of the world’s fish supply.
They share of the total world harvest produced through aquaculture has steadily increased over the past two decades and now accounts for nearly 20 per cent of world harvest.
One of the greatest challenges in fisheries management is the control of bycatch, the unintentional killing of species not intended to be caught, such as low value fish, immature fish, or even marine mammals. Fisheries are influenced by more than just fishing activity.
Fishery managers must also manage activities on land, such as agriculture, irrigation, pollution and development, that may impact critical fisheries habitat. Finally, fisheries exist in an environment that naturally fluctuates.
Events such as changes in ocean currents and temperatures can dramatically influence the size and health of fish stocks, making them more of a challenge to mange effectively.
It is becoming increasingly clear that the effective fisheries management, at both the policy making and the implementation stages, depends critically on agreement and participation that utilise objective and reliable reporting of fishery status and trends.