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Here is a compilation of essays on ‘Fishing’ for class 6, 7, 8, 9, 10, 11 and 12. Find paragraphs, long and short essays on ‘Fishing’ especially written for school and college students.
Essay on Fishing
Essay Contents:
- Essay on the Introduction to Fishing
- Essay on the Value of Fishing
- Essay on the Types of Fishing
- Essay on the Methods of Fishing
- Essay on the World Consumption of Fish
- Essay on the Species of Fish
- Essay on the Fishing Grounds in the High Altitudes
- Essay on the Conservation of Fish
Essay # 1. Introduction to Fishing:
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The term fishing embraces all aspects of man’s pursuit of the aquatic animals in the seas and in inland waters all over the world. A very wide variety of methods is employed. Men were hunters and fishermen before they became cultivators, and fishing is therefore one of the oldest occupations of mankind.
Increasing human numbers will make the efficient harvesting of food from the sea more and more important. Fish are a vital source of food, especially in countries like Norway, Iceland and Japan where the land is bleak or mountainous and agriculture cannot be easily developed; and fish are also caught and processed to produce lubricants, fertilizers or cosmetics.
Moreover, modern fisheries are not confined to catching fish, but include many other sea harvests such as whales, seals, pearls, crustaceans (i.e., lobsters, crabs, prawns, shrimps), molluscs (i.e. oysters, mussels, cockles, clams), sponges and seaweeds.
However it must not be assumed that fish and other marine animals are an inexhaustible resource. Indeed, there are vast areas of the oceans which have very few fish. Many factors affect the productivity of the seas; the depth of the water, the ocean currents, the temperature and salinity determine the amount of plankton or fish-food present. In a way fishing is like mining; it is a robber industry. If men catch fish at a rate faster than nature can replace them, there will eventually be very few left.
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With faster, highly-powered boats and extremely efficient and deadly ‘weapons’ for harvesting fish, many parts of the world are already faced by a great decline in the annual fish catch. Men now have to go further into the oceans to bring ashore sufficient hauls to meet their daily needs.
Overfishing and especially the wasteful killing of immature fish must be checked, not just by individual countries, but, as fish know no national boundaries, on an international basis. Fish protection and conservation measures in world fisheries must be promptly acted upon by all nations if the supply of this important source of human food is to be preserved.
Essay # 2. Value of Fishing:
In terms of food value, fish are in no way inferior to other forms of meat. They are tasty, tender and easily digestible. Different kinds of fish vary in their palatability and individual taste, while different methods of preparation (fresh, pickled, kippered or smoked) and of cooking (steaming, boiling or frying) mean that fish suit almost every taste and are highly prized all round the world.
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Moreover, fish and other marine products are rich in proteins which help in body-building or replace worn-out tissues. Their fat provides energy and forms a valuable source of reserve food for the human body. Many essential minerals are found in fish including iron, calcium, iodine, copper, magnesium and phosphorus, in relatively greater proportions than in many other foods. Fish-liver oils, e.g. cod-liver oil, are a very rich source of vitamins A and D. In fact, almost three-quarters of the total fish catch is used for food, whether fresh or processed.
Besides providing human food, fish and their by-products are equally useful in many other ways. The fish wastes from canneries are made into fish-meals, glues, oils and fertilizers. Whales provide an even greater range of industrial products. Before the invention of electricity or the discovery of petroleum, whale oil was the chief lamp-fuel and lubricant.
It is now used for the manufacture of soap, margarine, paints, ink and linoleum. Other by-products like wax and ambergris are used for cosmetics and perfumes and the bones and flesh are ground up for fertilizer. The skins of sea mammals like seals and walruses provide excellent fur clothing materials.
Other industries, besides those dealing directly with fish, are stimulated by fishing. These include shipbuilding and repairing, the manufacture of nets and other equipment, the construction of boxes or of tin cans for packing and the making of salt, ice or other preservatives.
Essay # 3. Types of Fishing:
In order to catch the different types of fish, fishermen must employ suitable nets or lines and must study the habits of the fish concerned.
On this basis the fishing industry can be divided into four main types:
i. Pelagic Fishing:
Pelagic fish are generally small in size and swim near the surface. Moreover they are found in large shoals. They may be caught close to the shore or far out at sea. The commonest methods used to catch pelagic fish are drifting and seining; drifters are larger and operate far from land, while seining is carried on by smaller craft working closer to the shore. In some areas, where the water is shallow, traps may even be used to catch pelagic fish.
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One of the most important habits of pelagic fish is their migration, and thus pelagic fishing is often a seasonal activity. For example, herring move from north to south in the waters off the eastern coast of Britain, from summer till the end of autumn. They are caught off the Orkneys and Shetlands in June, off the Scottish coast by August, around the Humber in September, and in the English Channel by the end of the year.
Similarly the pilchard is a summer visitor to south-west England, and the mackerel also comes to British waters in summer. The regular migratory habits of the pelagic fish impart an annual rhythm to the fishermen’s activities. They are able to make preparations for the catch, and fishing ports can get ready to handle the peak hauls. Even farmers can adjust their farm work to the fishing season and many of them take to part-time fishing, e.g. in Norway.
ii. Demersal Fishing:
Demersal fish (often known as white fish) live at the bottom of shallow seas. They prefer the cooler waters and are found most frequently at depths of about 40 metres (130 ft) where sunlight is just able to penetrate. They feed on smaller fish or sea animals and unlike the pelagic fish are not found in large shoals, nor do they have regular migratory habits. Cod is by far the most common and the most valuable of demersal fishes.
Trawling, where the sea-bed is smooth, or long-lining, where the bed is rocky or there are many wrecks, are the chief methods of catching demersal fish. Fishing trips are usually longer, lasting several weeks or months. Larger, more powerful boats, often equipped for processing and storing the fish, and a large crew are essential in demersal fishing.
iii. Inshore Fishing:
Fishing close to the shores, in shallow, sheltered, coastal waters and the lower stretches of rivers is important in both tropical and temperate regions. People of almost every coastal village in the world practise some form of fishing, usually within 5 km (3 miles) of the coastline.
The greatest number of part-time fishermen is found in inshore fishing and they supply fish for the daily food of the family or for the village market. Their methods are often less efficient than those used at sea though in some places, especially in Europe and North America, inshore fishing is both efficient and highly commercialized.
Casting nets, hooks and lines, trap nets, pound nets, gill nets and a wide range of wooden, bamboo, rattan or wicker-work traps are used. Some tropical fishermen also use sunken set nets, placing a conical net, held firmly by poles driven into the ground, at river estuaries. Large traps of kelongs made of stakes driven into the sea-floor may also be used along the coast, especially in South-East Asia, and fish are caught when the tide goes out.
A few pelagic and demersal fish are caught in inshore fishing but more important are the anadromous fish of which salmon is the leading species. Salmon are caught on their way back from the sea to their spawning grounds in the rivers. They return in large shoals in the same way as they first descended the streams after hatching in the head-waters.
Salmon are caught by haul seines and purse seines in coastal waters, while set-gill nets and drift-gill nets are placed across rivers and in estuarine waters. Local people also use a wide range of traps and hand-lines to catch salmon in the rivers. Trawlers also catch salmon at sea or in coastal waters but this is very destructive because many immature fish are killed.
A multitude of shellfish are harvested by inshore fishermen. These include the various types of crustaceans such as shrimps, prawns, lobsters and crabs, and molluscs like oysters, clams, cockles, mussels, limpets, whelks, winkles and scallops. Crustaceans are caught in a variety of traps.
Molluscs are collected from ‘beds’ where they cling to the rocks, or, when they are farmed, are kept in submerged wire boxes. Shellfish are very popular and have a world-wide market. They are thus commercially very important and constitute nearly 10 per cent of the world’s annual fish haul.
iv. Freshwater Fishing:
Freshwater fish are caught in streams, rivers, lakes, ponds and padi-fields. They are caught to supplement the diet of local people and are seldom exported. Salmon is the only exception. While most salmon are caught near the coast some may reach the higher reaches of rivers and be caught by rod and line or other methods. The Great Lakes of North America once contained large quantities of trout and Lake White-fish together with the pink and red salmon, but pollution has much reduced their numbers.
Other commercially-fished species in the lakes and rivers of North America include lake herring, yellow perch and blue pike. Fisherman use simple devices such as seines, gill nets, dip nets, fishing traps and lines. Most of the fish caught are consumed fresh, and the surplus is chilled, dried or turned into fish-meals and fertilizers.
Another inland fish which is much valued is the sturgeon. Both its flesh and roe are used. The latter is made into the Russian delicacy, caviar. The meat is frozen or canned. Sturgeon are found in the Black Sea and Caspian Sea, and in the larger rivers such as the Volga, Danube and Dnieper. In North America they are found in the St. Lawrence, the Mississippi and elsewhere.
In Europe, the various types of trout, closely related to the salmon, is much sought after by anglers. It is an excellent swimmer, like the salmon, leaping over waterfalls and rapids. It spends its entire life in the freshwater lakes or streams. The carp, which is indigenous to Asia, is bred in fish-ponds or caught in rivers, lakes and padi-fields on a commercial basis. Its flesh has a pleasant flavour and fetches good prices.
The carp and other related species such as roach, chub, bream, and tench have been bred in Europe and North America and been found popular but inland fish culture, especially for carp, is best developed in Japan and China.
Eels are fished or bred in many countries, especially Denmark, the Netherlands and the U.S.A. Inland freshwater fishing is only commercially significant when there are major rivers or large inland lakes, e.g. Tonle Sap in Kampuchea, Caspian Sea, Lake Titicaca and Lake Victoria. Man-made lakes such as Lake Volta in Ghana are also commercially fished.
Essay # 4. Methods of Fishing:
Fish are caught in many different ways; they can be caught by hand, with a spear or with a bow and arrows, but more advanced societies fish with traps, lines or nets. Commercial fishing is based on traditional techniques-the real difference comes in the scale of operations. Commercial catches must be large to recoup costs.
Many methods ensure that this is possible; larger and larger vessels are used, and these can use larger nets. Acoustic fish finders, radar, position finders and much other expensive modern equipment are used to track fish both night and day and factory ships are used so that the catch is quickly processed and fishing vessels do not have to return to harbor so frequently.
Four major methods are employed by modern fishing vessels:
i. Drifting:
Drift nets hang vertically in the sea, like a tennis-net. They are fitted with floats on the upper edge and weights below, and are usually placed just a few metres below the water surface where the fish will swim into the net. The fish are entangled by their gills and are unable to move either backwards or forwards because their heads are caught and their bodies are too big to get through.
Drift nets are used to catch pelagic fish such as herring, sardines, pilchards, anchovies, sprats and mackerel. For herring fishing, each drift net measures 55 by 14 metres (60 by 15 yards) and as many as 90 nets from a number of vessels may be used together to form a continuous curtain, stretching for 3 km (2 miles). Drift nets are used by powerful boats called drifters.
ii. Trawling:
The trawl net, a bag-shaped net whose mouth is kept open by otter boards or head- beams is by far the most efficient method of catching demersal fish like cod, haddock, plaice or sole. Its mouth has floats at the top and weights at the bottom, and the net is made stronger at the ‘cod end’ in which the fish are caught.
The net is dragged along the sea-bottom by a trawler for about 2 hours, at a speed of about 8 km.p.h. (5 m.p.h.). When the skipper is satisfied that a sufficient amount of fish has been trapped inside the net, the vessel stops and the net is hauled in.
The normal length of a trawl-net is about 46 metres (150 ft). Its use is, however, restricted to relatively smooth sea-beds for irregular and sharp pinnacles on the bottom will tear the net. Rough seas and stormy weather also interrupt fishing operations and endanger the lives of the fishermen.
Trawling requires much labour and a large modern factory trawler may have a crew of eighty or ninety people but normally trawlers carry about 30 hands. The trawler may operate from a fishing port spending several weeks at sea at a time and only short periods in the home base, so that a deck-hand on a trawler has a hard life. Trawling may be a seasonal occupation, as in Icelandic waters.
Factory trawlers are equipped with refrigerating plants and canning facilities. Some, such as the Japanese vessels fishing in the Atlantic, may be away from home for months, processing the fish on the spot.
Trawlers may send their catch ashore by craft that ply at high speeds between ports and the trawling boats, or may operate in a fleet with a large factory ship which processes the catch at sea.
iii. Seining:
Seine nets such as the haul seine and purse seine have intermediate features between drift and trawl nets. The haul seine is like a drift net, kept floating vertically in the sea like a wall by corks on top and weights below. After surrounding a shoal of fish, the net is dragged to the shore at both ends. The fish trapped in the net are then gathered immediately. The ring net, operated from small vessels, works in the same way.
The purse seine is more like a trawl net, with a narrow conical end and ‘wings’ of netting rather than otter boards. It is usually smaller and cheaper than a trawl and takes a smaller catch but is more convenient for use by smaller boats. However, some very large purse seines used by large vessels can catch 600 tonnes of fish at a time.
Although most seine nets are used close to the surface they can, with some modifications, as in the Danish Seine, be used very effectively for catching demersal fish too. The fish are directed into the net by the ‘wings’ which are fastened to long ropes. The ropes are then drawn to a stationary ship, forcing the fish into the centre of the net. By closing the bottom with a draw string, the fish are prevented from escaping beneath the net and the seine is finally hauled on board.
iv. Lining:
Line fishing was much more important before the invention of the nets mentioned above, especially the trawl. It is still commercially employed in certain types of demersal fishing, particularly where the sea-floor is rugged and likely to damage trawl nets. It is also used for catching large fish like the tuna. Commercial lines are of two types: hand-lines (or haul-lines) and long-lines (or trawl-lines).
Each hand-line has a single baited hook, cast from the deck and drawn up by individual fishermen when the float shows that the fish is hooked. Its commercial importance is limited because it is obviously slow and uneconomical for deep-sea fishing. However, it is most popular for sport-fishing.
Long-lines may have as many as 500 to 5,000 hooks attached, a few metres apart, to a single mainline which is buoyed at each end. The line, sometimes several kilometres long, is towed along by dories (small flat-bottomed rowing boats), or by large steam vessels. The hooks are drawn up by a team of deckhands who unhook the fish caught and rebait the hooks before casting the line into the sea again.
In this way, deep-sea fish like cod, e.g. on the Grand Banks, halibut and hake may be fished. For hooking large fish exceeding 18 kg (40 lb) several lines are run to a single hook and a man is assigned to each line to haul in the fish. The baits used for deep-sea line fishing include worms; squids and cuttlefish; mussels, whelks, limpets and other shell-fish; eels, herrings, razor fish, and ray’s liver.
Essay # 5. World Consumption of Fish:
The annual world fish catch is more than 73.5 million tonnes. Of this, Asia accounts for over 44 per cent; Europe (including the U.S.S.R.) 32 per cent; North America, 7 per cent, and the rest of the world the remaining 17 per cent. Annual fish consumption per capita is greatest in Portugal and Japan (over 45 kg/ 100 lb per year).
Denmark, Norway and Sweden (27— 41 kg/60-90 lb), Taiwan (36 kg/80 lb) and Asian countries, e.g. Malaysia (29 kg/65 lb) are also major consumers. Advanced countries where meat is easily available such as the U.K (13.5 kg/30 lb), U.S.A. (9 kg/20 lb) or Australia (9 kg/20 lb) tend to consume little fish.
Per capita consumption varies for two reasons:
Firstly, fish is relatively cheaper than meat and is thus in demand in many underdeveloped or partially-developed countries. It is therefore consumed in great quantities in many Asian countries, e.g. China, and in the poorer European countries, e.g. Portugal, Spain. The consumption of a number of European countries is boosted by the weekly fast of Catholics, when fish rather than meat must be eaten.
Secondly, fish is an important source of protein for countries whose agricultural potential is low.
Mountainous Japan and Norway are therefore large consumers. This pattern may be perpetuated by tradition. Thus many European nations, e.g. Denmark, Germany, still have relatively high fish consumption figures though fishing is less important in the overall economy than formerly.
It is important to note that South America in general (despite the dominance of the Catholic religion) consumes little fish because of the importance of ranching, e.g. Argentina (5 kg/11 lb per capita). Australia also has a low fish consumption.
Essay # 6. Species of Fish:
Generally speaking there are two main types of fish: salt-water fish which spend their entire lives in the oceans and seas, and freshwater fish which are found in inland streams, rivers and lakes. There are some anadromous fish, chiefly the salmon, which are spawned in the inland rivers, but spend most of their lives in the seas and only return to the rivers to spawn and die.
The largest group is that of salt-water fish and these may be further sub-divided according to their habits. Some such as the herring or sardine live in large shoals, others live individually. This affects the methods which are used to catch them but by far the most important determinant of fishing method is whether the fish are pelagic, i.e. living at or near the surface like herring, or demersal, i.e. bottom-living like cod, haddock or plaice.
i. Salt-Water Fish:
There are thousands of species of fish in the seas and oceans, but the most numerous is the herring. By weight herring is the most important catch of the North Atlantic region and is also the chief fish caught in Japan and China.
The herring is a small fish, between 20 and 38 cm (8 and 15 inches) long. It is cheap, palatable and nourishing but does not keep well. It is usually consumed fresh and needs to be marketed very promptly. The amount of herring caught is much in excess of local consumption and a large proportion of the catch is normally preserved by being either kippered, pickled, smoked, canned or frozen.
Herring are pelagic fish and are found in large shoals which may be 14 km (9 miles) in length and 6 km (4 miles) in width and comprise as many as 700,000 herrings. They swim between 15 and 30 metres (50 and 100 ft) below the surface and are caught by drifters, usually at night, because they swim deeper during the day.
The mackerel is another pelagic fish about 40 cm (6 inches) in length. It is tasty but perishable and is best consumed fresh. It is often found to the south of the main herring areas, e.g. in the Mediterranean Sea, off southern Scandinavia, off Cornwall (Britain), in the waters off Carolina (U.S.A.) and in the Yellow Sea.
The busiest mackerel season in Western Europe is from May to September, when the fish are found in large shoals near the surface of the water. At night they are identified by the distinct glow they throw on the surface water. They are caught by seine nets or purse seines.
Other pelagic fish caught in abundance in most temperate waters are sardines (a name derived from the Italian island of Sardinia), pilchards (slightly larger than the sardine) brisling and anchovies. These species are similar to the herring but are usually much smaller.
Large quantities of sardines and pilchards are caught in the Mediterranean Sea, the Bay of Biscay and along the coast of the New England States, especially Maine, and are usually canned. Brisling are caught off southern Norway. The sardines and similar small fish are washed, beheaded and gutted and then lightly brined. Tomato sauce or oil is added, and the cans are sealed and cooked.
After cooling, the cans are labelled and packed for export. Anchovies are also caught off Europe but most come from Peru where 90 per cent of the catch is made up of these fish. Anchovies are very small. Some are preserved in vinegar and spices or made into sauce, but the vast majority are converted into fish meal, fertilizers, oil or glue.
Menhaden, a pelagic fish which occurs in enormous shoals, was once almost ignored because its oily nature made it unsuitable for human consumption. It is now extensively fished off America from Newfoundland to the Caribbean Sea. The U.S.A. is the leading menhaden catcher and this fish accounts for about 30 per cent of the U.S.A.’s total catch.
Almost all the menhaden is made into fish-meal for animal feeding, or into fertilizers because of its high nitrate and phosphorus content. A small amount is now processed by special machinery which removes the oil, and is then canned. A similar fish, with similar uses is the capelin caught in the North-East Atlantic.
The most important of the demersal fish is the cod and in terms of value it is more important than herring. It is a large fish measuring up to 1.5 metres (5 ft) in length and lives near the bottom of shallow seas. It is found in the North Sea, off Norway and Iceland and on the Grand Banks off Newfoundland, and lives by preying on herring or their eggs. It is caught by trawl nets. The cod is very palatable and nourishing. It is mostly sold fresh or smoked and the oil is extracted to make cod liver oil.
The other demersal fish or white fish include the haddock (1 metre/3 ft) which is particularly important in the North Atlantic; the halibut (2 metres/7 ft) caught chiefly off British Columbia and north-western U.S.A.; and hake (1.2 metres/4 ft). Flatfish like plaice (as long as 1 metre/3 ft), sole (about 46 cm/18 inches) and flounder are also important and fetch high prices. These species as well as skate (2 metres/7 ft), dab, brill, catfish, dogfish and many others are caught by trawlers.
The tuna or tunny is a large member of the mackerel family, measuring up to 3 or 4 metres (10 or 13 ft) and weighing as much as half a tonne. It is found in the deep seas and oceans and lives by preying on smaller fish. It has been caught for centuries, especially by the Japanese, and it was also fished in the Mediterranean Sea in the days of the Roman Empire.
It really only attained commercial importance, however, at the beginning of the twentieth century when the art of canning became known. Nowadays almost all tuna is canned. It is caught off Japan and in the Indian Ocean and also in the eastern Pacific where California is the leading tuna-fishing state. Apart from the flesh, which is canned, the liver is also highly prized because of its nutritional value.
ii. Freshwater Fish:
In terms of commercial value, freshwater fish are less important than those of the seas. They rarely swim in large shoals and the fishing areas are rather restricted. In North America and Europe freshwater fishing for trout, perch, pike or salmon in rivers and lakes is a part-time or hobby occupation.
The Great Lakes, once teeming with many kinds of fish, especially the Lake Whitefish, are no longer important because of pollution. Inland fishing is most important in the U.S.S.R. and in East Asia. The sturgeon, highly valued for both its flesh and its roe (eggs) is fished chiefly in the Caspian Sea. Other river and lake fisheries in the U.S.S.R. are also important.
In China and Japan inland fishing in rivers, lakes and padi-fields is extremely important and fish farming is also practised. The chief species is the carp. In India, Pakistan and Bangladesh inland fishing is also extremely important, accounting for between one-third and one-half of the total catch of these countries.
iii. Anadromous Fish:
The salmon is the most important fish in this category and is extensively fished in North America, particularly from Alaska to Oregon on the Pacific coast. There are five major species of salmon- the chinook, humpback, sockeye, silver and chum. The young salmon live in the sea but after 2 to 5 years they return to the stream where they were born to lay their own eggs or die.
They travel in large numbers over long distances, and, by some peculiar instinct, find their original breeding ground. Their migration routes and spawning grounds are readily spotted, and they are easily caught by traps or nets. Salmon is a very valuable fish and fetches high prices whether fresh, smoked or canned. In the early days, fishermen used to place large fishwheels across the streams and intercept the salmon- run so that the fish were flung up into boats anchored downstream.
Today, however, the use of fish wheels is illegal, because they make a clean catch of the entire salmon run, and no fish remain to spawn and return in the following seasons. Other obstructions, such as dams which prevent the salmon from reaching their spawning grounds in the headwaters, also threaten the reproduction of salmon.
Salmon-fishing in American and Canadian waters has been important for more than a century, but today the greatest haul is in Alaska, which alone accounts for more than three-quarters of the annual American salmon output. In Canada salmon is the leading fish species by value. The bulk is canned and there are many canneries along the Pacific coast in ports such as Seattle, Vancouver, Port Edward and Astoria that deal with salmon alone.
The world’s salmon catches are declining faster than those of any other species. Overfishing, pollution of streams, logging (which jams rivers) and the erection of dams for H.E.P. generation have all contributed to the depletion of salmon numbers. The Columbia River, which once yielded US$10 million worth of salmon in a year, has had very few salmon since the 1930s. Effective and internationally-accepted conservation measures must be devised and efficiently operated if salmon are not to be completely eliminated.
Essay # 7. Fishing Grounds in the High Altitudes:
The importance of the northern hemisphere in fishing can be explained by the fact that it is a land hemisphere with a large population and with a great length of indented coastline providing many harbours. Moreover fish are more plentiful in certain areas than in others because of the availability of plankton.
The reasons for the concentration of fishing grounds in the high-latitudes may be outlined as follows:
i. Supply of Plankton:
Plankton is a collective term for the millions of microscopically-small organisms which are found in sea-water. Phyto- plankton are tiny plant organisms drifting about in the water at or near the surface. They form the food of the zooplankton (microscopic animals) which are in turn devoured by other sea creatures such as fish. The fish are in turn eaten by larger fish and sea mammals, such as seals and whales.
The most important conditions for the presence of plankton are:
(a) Shallow waters:
Phytoplankton at the base of the food pyramid depend on sunlight for their existence, so they can only develop properly in shallow seas. The best fishing grounds are thus located above continental shelves which are not more than 200 metres (660 ft) below the water surface, where plankton of all kinds are most abundant.
The world’s most extensive continental shelves are located in high or mid-latitudes in the northern hemisphere, e.g. the ‘banks’ off Newfoundland; the North Sea and continental shelf off N.W. Europe; the Sea of Japan. These areas have other advantages for plankton development besides shallow water.
(b) Cool waters:
Plankton thrive best in cold or cool waters. Thus they are plentiful in polar waters, at the meeting of cold and warm ocean currents as on the Newfoundland ‘banks’ and the Sea of Japan, or where cold water from the ocean floor wells up to the surface as it does off the west coast of South America. The continental shelves of the tropics are relatively less rich in plankton because the water is warm.
(c) Land-derived minerals:
Plankton are nourished by mineral salts and other material brought from the land by rivers or ice. They are therefore most plentiful in coastal waters where such materials are most abundant.
ii. Cool Climate:
It has been found that marine life is best developed in oceans with a temperature lower than 20° C (68° F). Tropical waters are too warm and the fish species are generally of less commercial value. The cool waters of the temperate latitudes are more suited to marine life, and the most valuable fish, like cod, plaice, herring, haddock, mackerel, sole and salmon are found there.
Furthermore, fish cannot be kept long in hot, moist tropical conditions and tend to deteriorate rapidly. In temperate lands the cold winters originally provided natural ice for preserving the fish. Refrigeration and canning have now made both temperate and tropical fishing less susceptible to the hazards of climate, but in many parts of the tropics, ice-factories and other facilities are still lacking.
iii. Physical and Environmental Influences:
Both the Atlantic and Pacific coastlines of the middle and high latitudes in the northern hemisphere are very much indented and are backed by strong relief. There are sheltered inlets and estuarine coasts that make ideal sites for fishing ports and villages. Some of the greatest fishing ports of the world include Grimsby, Reykjavik, Bergen, Stavanger, Boston, St. John’s (Newfoundland), Hakodate, Tianjin (Tientsin).
The rugged mountains and the short growing season in Norway, Hokkaido, Iceland, Alaska and other areas restrict agricultural activities and people take to the sea to enrich their diet. Norway’s arable land accounts for only 3 per cent of its total area, and that of Newfoundland is not even 1 per cent.
Fishing and shipbuilding have thus become major occupations. The temperate forests, providing both soft and hardwoods for the construction of fishing boats, barrels, and casks as well as pitch for waterproofing were also once decisive factors in the development of the fishing industry.
Those areas in the southern hemisphere which might otherwise develop fishing industries are hampered either by lack of harbours, or of labour, e.g. on the indented but sparsely inhabited coasts of southern Chile. Elsewhere, e.g. in Argentina and Australia meat and other foodstuffs are so plentiful that it has not been necessary to develop a fishing industry.
iv. Moderate or Large Population:
Fishing has always been a labour-intensive industry and modern equipment has only recently begun to change this situation. Not only fishermen are involved but those who process the catch by cutting, cleaning, salting, smoking, pickling, drying or canning the fish. Small-scale fishing is thus important in well-populated areas such as China and Japan.
On board large, modern craft fish can be preserved in salt and ice, so that such vessels can operate off relatively sparsely peopled coasts in the Arctic Ocean or the North-East Pacific. More important than labour is market. The large population of Europe, North America, China, Japan and the U.S.S.R. create a continuous demand for fish and efficient communications enable the fish to be quickly distributed to markets in fresh or processed state.
Essay # 8. Conservation of Fish:
Fish lay enormous numbers of eggs but many of these, as well as many young fish, never survive to maturity. It is estimated that a herring lays an average of 100,000 eggs, a cod between 5 and 10 million, and the female oyster something like 60 million eggs within a spawning season. But small fish eat many of the eggs as well as plankton.
Larger fish eat the smaller fish which in turn are caught by the largest marine animals or by men. Without the interference of Man the small fraction of young fish which survives is sufficient to maintain the world fish population, but fishing by Man has upset the natural balance.
It was once thought that sea fisheries were inexhaustible and even until the mid-nineteenth century, most people still believed that men would not seriously affect the number of fish. Statistics reveal however that with greater efficiency in fishing, there has been a serious depletion of the world’s fish and sea mammals. Some common species have now become rare, and in the case of whales, some have been practically wiped out.
No comprehensive statistics are available on the resources of the sea as a whole but records kept by individual fishing nations show that vigorous exploitation of the sea in any region leads to a decline in catches. Fishermen now have to sail further and more boats have to be employed to maintain the supply of fish.
There are many reasons for the decline of the world’s fish hauls: overfishing; indiscriminate fishing of immature fish; pollution of the water by chemical plants and factories; and ignorance of fish culture. If men wish to prevent further loss of this vital source of human food, especially when human numbers are increasing so fast, fish conservation must be practised on a global basis.