CHAPTER IINTRODUCTION

THEFISHING INDUSTRY

Inits essential features the story of the gradual rise and development of the fishing industry closely resembles that of its sister industry, agriculture. In both cases man became skilled in harvesting long before he understood anything of the art of cultivation. Primitive man roamed from place to place in the wake of the annual wave of harvest, gathering wild crops of grain, berries and fruits. Ultimately he became alive to the significance of seed, and the nomad settled down to raise crops year after year in the same place. Gradually he acquired a knowledge of the conditions of temperature, moisture, and quality of soil that favoured the growth of his plants. Finally, he discovered the principle of the rotation of crops, and, by this, not only increased the productivity of his land but also laid the foundations of a systematic agriculture. Of recent years agriculture has been rapidly developing into a science. Chemistry, physics, botany, plant physiology, and bacteriology, all contribute increasingly to a full understanding of the inner processes of the growing plant, and indicate more and more clearly the exact relations that exist between the conditions of growth and the character and amount of the resulting product.

The art of fishing is one of the oldest in the world, yet even to this day the fisherman is simply a hunter, gathering where he has not sown, and differing little, save in mechanical efficiency, from his primitive ancestor fishing with spear and trap.

Only in recent years has any systematic attempt been made to understand something of the forces that produce the annual harvest of the sea. We know very little about the habits of the various fishes that constitute this harvest—their food, their migrations, their reproductive processes, and, in general, the conditions upon which their healthy life and development depend. We have developed highly efficient fishing implements, but we have yet to learn to use them wisely and not too well; to increase the fertility of the various fishing grounds rather than depopulate them by over-fishing and the destruction of immature fish.

The fisherman’s harvest differs from that of the farmer in one important respect. Fishes grow for three or four, or more, years before they are mature. Now, only mature fish as a rule have any considerable commercial value, and only mature fish are able to reproduce their kind and so maintain the existence of the fishery. On the fishing grounds, both mature and immature fish are mingled together, and in capturing the one it is practically impossible to avoid netting the other. To some extent the capture of immature fish is avoided by making the mesh of the net of such a size that the smaller fish can escape. With drift nets only mature fish are caught, the small ones escaping; but with trawl nets it is otherwise. The trawl net is essentially a large string bag that is drawn open-mouthed along the sea bottom, scooping up wholesale all bottom-living fish, such as cod, haddock, sole and plaice. All go into the net, both large and small, and, although the youngfish ultimately escape through the meshes, many of them are damaged in so doing, while many young, flat fish, lying on the sea bottom, are damaged by the foot rope of the net, as it passes over them. Certain fishing grounds, such as the Dogger Bank, were almost depopulated of flat fish in the years just previous to the war.

Fortunately for the future of the fisheries, the trawl, can only be worked on smooth ground, and at depths not exceeding two hundred and fifty fathoms, so that only a small percentage of the actual fishing grounds is affected by it. Also, when a fishing ground shows signs of becoming exhausted by over-fishing, it is less frequented by fishermen, owing to the reduced catches that can be obtained, and thus it tends automatically to recover. Nevertheless, it is desirable that fishing should be so organized and restrained, that the fertility of the fishing grounds is not imperilled. In the distant future it may become possible to re-stock partially exhausted grounds with young fish, artificially reared in a hatchery.

Oceanography—the study of the ocean and its inhabitants—is one of the youngest of sciences. Yet, to an island people such as we are, it should be one of the most important, for it is only by the study of oceanography that we can hope to found a systematic, organized aquiculture.

The beginning of a simple aquiculture is to be seen in the cultivation of shellfish, such as oysters and mussels, by the inshore fishermen.

Of recent years, experiments have been carried out by the Fishery Boards of England, Scotland, Germany, and the United States of America, with the object of increasing the productivity of certain fishing grounds by adding large numbers of artificially hatched, youngfish. For some years the Fishery Board for Scotland added annually about twenty million plaice larvae to certain confined sea areas (Upper Loch Fyne), and found, as a result, that the number of young plaice on the shallow beaches was doubled.

In some cases a new species of fish has been introduced into a particular fishing ground, with marked success. Thus the U.S.A. fisheries collected and hatched the eggs of the shad on the Atlantic coast and introduced the larvae into the Pacific, with the result that a profitable shad fishery has now been established on the Californian coast.

The application of science to the fishing industry is not restricted to biological investigations of the food, habits and development of living fishes. It is developing new processes for the better preservation of edible fish for food purposes, so that the large quantities of fish caught periodically—for example, in the summer herring fishery—may be stored up for gradual consumption during the winter. It has shown that fish waste can be manufactured into glue, cattle food, and fertilizers. It has developed into a profitable industry the extraction of oils from both edible and inedible fish, and the conversion of these oils into hard fats, suitable for the manufacture of soap and margarine. It has demonstrated that the skins of certain fish, notably the shark, can be tanned to make excellent leather.

With the exception of these pioneer experiments and investigations, however, the fishing industry of to-day is simply an organized art—the art of catching wild fish. The story of the industry is essentially a description of the methods that are used for capturing the various species of fish that are of commercial importance, and for handling, curing, and disposing of the catch.

Great Britain is situated in the midst of the greatestfishing grounds of the world. The British fishing industry is the most efficient and the most highly developed of any. Consequently, since fishing methods are essentially the same everywhere, it will be sufficient for us to consider, with few exceptions, the methods and equipment that are used by our own fishermen around our own shores.

There is direct evidence that, as early as the third century,A.D., fish were caught in considerable quantities round the coast of Britain by the natives and used as food. Little is known about the early development of a fishing industry in this country. We know that in the fourteenth and fifteenth centuries, fish was in demand throughout the country, partly because of the religious observance of fast days, and partly, no doubt, because it afforded a welcome change in the regular winter diet of salted meat. In those days there was no winter root crop, so that cattle were killed in autumn and salted down for consumption during the winter.

In disposing of their catch, the fishermen were handicapped by the almost complete lack of transport facilities from the coast inland. Their produce would be distributed by pack-horse, so that fresh fish would be practically unknown beyond a distance of a few miles from the coast. Consequently, all fish for inland markets were salted. The fish were pickled in brine, as the art of dry-salting was then unknown in this country.

To develop a successful fishing industry, it was necessary, then, as it is to-day, either to dispose of the catch quickly on the spot, or to preserve the fish so that it could be transported to distant markets. In 1347, a Dutchman, William Beukels, of Biervelt, invented an improved means of curing and pickling herring, which was essentially the modern process of gutting the fish and packing them in dry salt. At this time theBaltic herring fishery, carried on by the Hanseatic League, dominated the markets of Europe. But the new method of curing, exploited by the Dutch, improved the quality and keeping powers of the fish to such an extent that, by the end of the fifteenth century, the Dutch fishing industry was supreme, and had become a powerful and valuable national enterprise. In the sixteenth century, as many as two thousand Dutch herring “busses” (as the boats were called) would gather on St. John’s day at Brassa Sound, in the Shetlands, to begin the summer herring fishery. The fish were caught with drift nets, were salted and packed in barrels, and carried home by the fast-sailing, attendant “yaggers.” Ashore they were repacked in fresh salt in new barrels. Over a million barrels were packed in a year. When caught, the fish would be worth about a million pounds, and when retailed about two million pounds. Contemporary illustrations of the methods of curing and salting then in use reveal the astonishing fact that even to the smallest detail the methods that were employed in Holland in Elizabeth’s day are identical with those that are employed at Yarmouth to-day.

As a direct result of the great development of their trade in salted herrings, the Dutch gradually gained a naval and maritime supremacy in Europe which they maintained until it was wrested from them by the English.

English sea-power in the early years of the sixteenth century was in a decadent condition. The ports and harbours had been neglected, and had become silted up, so that the condition of the shipping industry in general, and of the Navy in particular, had reached a very low ebb. In 1561, Mr. Secretary Cecil, alarmed by the growing menace of the Dutch naval ascendancy, proposedthree remedies for restoring the strength and importance of the navy. He proposed:

(1) That the fishing industry be promoted, as it provided a valuable recruiting ground for the navy;

(2) That merchandise be extended, and so provide increased employment for the shipping industry;

(3) That piracy be encouraged, privately-owned privateers forming valuable auxiliaries in time of war.

He thought that the fishing industry could be stimulated immediately by renewing the fast days, which had fallen into disuse since the abolition of the monasteries.

He suggested that two days a week—Wednesday and Friday—should be meatless days.

In 1563, he tried a measure of Protection, a Navigation Act being passed, making it illegal to buy or sell foreign-caught fish, and attempts were made to prevent Dutch and other foreigners from fishing in English waters. These measures, although passed by Parliament, do not appear to have been enforced.

James I issued two proclamations, imposing licences and dues upon foreign fishing vessels fishing in British waters. No attention was paid to these, and it was left to Charles I, some years later, to enforce them. Other steps taken by both Charles I and Charles II consisted mainly in the formation of Royal Fishery Companies. Various fishery companies and societies succeeded one another up to the end of the eighteenth century. They do not appear to have been successful in establishing a flourishing fishing industry, and in 1718 (George I) an act was passed by which fishermen were to be rewarded for their catch by a bounty. Bounties were to be paid for several kinds of fish: thus, for every barrel of white herrings of 32 gallons, exported beyond the seas, the bounty was 2s. 8d.; for full red herrings, 1s. 9d. per barrel; for empty red herrings, 1s. per barrel.

The conditions upon which the bounty was to be paid were fully set forth in a later act in 1750 (George II). The construction of herring vessels was encouraged by a bounty of 30s. per ton, paid out of the Customs, for decked fishing vessels of from twenty to eighty tons.

The time and place of fishing were stipulated, as well as rules for the proper management and prosecution of the fishery. Each vessel was to have on board twelve Winchester bushels of salt for every last of fish such vessel was capable of holding, the salt to be contained in new barrels.

In 1757, the bounty was increased to 50s. per ton, but was reduced to 30s. again in 1771. It was further reduced to 20s. in 1787, and an additional bounty of 4s. per barrel added. This was made proportional to the tonnage, so that no vessel could claim more than 30s. per ton—unless the vessel caught over three barrels per ton, in which case a bounty of 1s. per barrel was granted upon the surplus quantity.

While the bounty often undoubtedly encouraged the development of the fishery, the development was not so rapid or so extensive as it would otherwise have been, owing to the duty on imported salt. The weight of the duty was such that the fishermen threw fish overboard rather than cure it, only landing that which could be brought in fresh.

In 1808 the bounty was raised to £3 per ton on every British built and British owned fishing boat of not less than sixty tons burden, properly manned, registered, and navigated and employed in herring fishing. The maximum tonnage on which the bounty was payable was one hundred tons. Two shillings per barrel was paid on properly cured and packed herrings.

After the peace of 1815, the naval wars and the press gangs had reduced the sea fisheries to negligibleproportions, but the existing bounties were continued until 1829, and encouraged the rapid revival of the industry. By 1829, the fishing industry was well established, and thereafter steadily developed in value and importance.

The modern organization and development of the fishing industry began between 1870 and 1880, following the introduction of steam fishing vessels. The old sailing smacks and drifters were necessarily limited in their scope and capacity. They could only fish in certain weathers; they required skilled handling; their effective area of operation was restricted by the necessity for bringing the catch ashore as fresh as possible; their trawling power depended upon the wind.

A sail boat was generally the property of a small family group of fishermen, who worked the boat and fished, while one of their number—the ship’s husband—stayed ashore to purchase stores and tackle, and dispose of the catch. The proceeds of the boat were shared among the owners. These privately owned sail boats were to be found in every little harbour on every coast of Britain. The fishermen themselves were a fine, sturdy, independent class of men, skilful seamen, and all-round fishermen, able to turn their hands to any form of fishing, whether lining, trawling, or drifting.

The introduction of steam trawlers and drifters has completely changed the character and organization of the fishing industry. Instead of being individualistic, it has become collective, and instead of being the common industry of every seaside village, it has become controlled by large limited liability companies, and centralized in a few large ports.

Steamers were first used in 1870, to collect the catch from the sail boats on the fishing grounds, bringing it home with all speed while the fishing boats remained atsea. This naturally enabled the fishing boats to catch more fish, and also made possible the use of larger boats fishing further afield. A logical development of this step was the construction of actual steam-driven fishing boats—trawlers and drifters. These steamers soon proved to be superior to the sail boats. They were able to fish in all weathers, even in a calm. Owing to their greater power, also, they were able to use much larger nets and fish in deeper waters.

Steam trawlers and drifters are much more expensive than smacks or sailing drifters. They can only be berthed and handled satisfactorily in harbours that are equipped for the unloading and dispatching of large quantities of fish. From the very beginning these steamers were owned by large limited companies rather than by individuals, and the industry has tended to become more and more centralized at certain large ports, for example, Aberdeen, Hull, Grimsby, Yarmouth, Lowestoft, Milford Haven, and Fleetwood. The rise and development of many of these ports, for example, Aberdeen and Fleetwood, has been in direct response to the demands made upon them by the new steam fishing industry.

The introduction of steam fishing made longer voyages possible, and led to the development of new fishing grounds. Steam trawlers from British ports now fish as far north as Iceland and the White Sea, as far west as Newfoundland, and as far south as Morocco, making voyages of many week’s duration.

The re-organization of the fishing industry led to specialization amongst the fishermen themselves. The old sailing fisherman was essentially an all-round man. He was equally expert at lining, drifting and trawling. The skipper of a steamer, however, is a specialist; he is either a liner-, a drifter-, or a trawler-man. Generally,also, he keeps to a given region—Iceland, the White Sea, the North of Scotland, the North Sea, or the Bay of Biscay.

In the three years preceding the war (1911 to 1914) the development of the steam fishing industry had become almost stationary. This was probably due in part to over-capitalization, resulting in lower profits. It was feared also that the greatly increased efficiency of the steam trawlers tended to produce a condition of over-fishing in certain areas, with the result that catches obtained in those areas progressively diminished; for example, the average catch per boat per day in the North Sea during three successive periods was as follows—

1903 to 190617·2cwts.1907 to 191016·7„1911 to 191315·3„

The fishermen became alarmed and development was arrested. This tendency to over-fish certain grounds has been effectively checked during the war by the almost complete cessation of offshore fishing. There is thus every probability that such grounds have now recovered, and further that, in many cases, grounds such as the Dogger Bank, that had become almost depopulated, will have become restocked.

The successful development of steam fishing has necessarily reacted upon the prosperity of the individual fishermen in the various fishing villages, with their smaller, privately-owned sail boats. They were faced with two alternatives: either to combine together to acquire steamers, and so maintain their position in the offshore fisheries, or to devote their attention to the development of inshore fishing. Many of the larger sailing drifters have now been fitted with petrol engines,which make it possible for them to compete with the steam drifters for herring and mackerel.

Generally speaking, however, the outlook for the small fishermen of the English and Scottish coast villages—the real fisher folk—is discouraging. The tendency of legislation, however, just before the war was to encourage this class of fishermen by restricting the operations of the steam trawlers in certain localities. In 1910-1914, with the object of protecting the inshore fishermen, the Fishery Board of Scotland prohibited trawling in the Moray Firth area, only drifting and lining being permitted. Since this prohibition only applied to British subjects, certain East Coast fishing companies evaded it by transferring their vessels to foreign flags, registering them in a foreign port and employing a foreigner as a dummy skipper. The Board secured convictions against these offenders in the Sheriff’s Court, but the convictions were upset subsequently by the Foreign Office. The original prohibition was then strengthened by a new law which made it illegal to land fish in Scotland, if caught by vessels registered in a foreign port.

During the war, the inshore fisherman found himself in a comparatively advantageous position, as the high price of coal made steam fishing less profitable. Further, the offshore trawling grounds were mostly closed, and the majority of the steam trawlers and drifters were on war-service. For the time being, therefore, inshore fishing with smacks was placed at an advantage.

A number of fishermen’s co-operative societies were formed to organize the sale and distribution of the produce of these inshore fisheries. This also tended to make the position of the inshore fisherman more secure.

The old order changeth, and although there is that connected with this transformation in the fishingindustry which is to be regretted, yet, on the whole, the developments of the past forty years have undoubtedly transformed the fishing industry into a very efficient and valuable national asset. Individually, the present-day steam fisherman is very much inferior to his sailing predecessor. The centralization of the industry in a few big ports, although undoubtedly making for much greater efficiency, bears hardly on the type of the old class of expert fishermen; but these are the almost inevitable consequences of such a transition.

But what is the present condition of the industry, and what is its future likely to be? The prosperity of the inshore fisherman, as well as that of his offshore rival, is vitally important to the welfare of this country; there should be room and opportunity enough for both. The inshore fisherman, protected by legislation and secured by well-organized co-operation, can increase very considerably the amount of our available home-grown food supply. The superior power and equipment of the big steam trawlers and drifters, properly utilized and encouraged, should be one of the most valuable industrial assets of the State. We are not a great food-producing nation; on the contrary, in the years before the war, we actually imported more than 40 per cent of our total food requirements. We are surrounded by seas that teem with every form of edible fish. British enterprise has built up a fishing industry which is the greatest and most efficient in the world. In 1914, our fishing boats were practically equal in numbers and equipment to those of all the other countries in North-West Europe put together. Nearly 70 per cent of the fishing boats in the North Sea were British. The total produce of our sea fisheries has nearly doubled since the beginning of the century. The annual catch in the last few years before the waraveraged over a million tons. It was worth about fifteen million pounds when landed, and may be valued at nearly fifty million pounds by the time it reached the consumers. Of all this splendid food that is obtained at our very doors by our own people, less than half is retained for consumption in this country. Out of 600,000 tons of herrings landed annually in this country before the war, over 500,000 were exported, chiefly to European countries. Herrings have a high food value, and contain a large amount of easily digested fat, and if all the herrings landed in this country were consumed at home, it would only allow two herrings a week to each adult individual in all the population. An increased home consumption of fish, would effect a corresponding saving in imported meat.

Owing to this remarkably small home demand for fish, the fisherman has had to depend upon foreign markets, chiefly Germany, Poland, Russia and the Levant. The present adverse rate of exchange with these countries, and the increased cost of fishing operations, make it impossible for the foreign importer to take our fish, except on terms which our fishermen cannot consider. These markets are therefore closed, and unless other outlets are found for its produce, the industry will be threatened with ruin.

In 1920, the Government guaranteed the cure of herrings up to 880,000 barrels; unfortunately, they were only able to dispose of them in European markets at a great loss. The Government, therefore, have decided this year (1921) to withdraw their guarantee.

It would seem that, in view of the present failure of the foreign markets, vigorous steps should be taken to encourage the consumption of fish in this country, and so preserve this valuable industry from ruin. A national scheme of development should be inaugurated, havingfor its objects, (1) the systematic exploitation of local and periodic coastal fisheries; (2) the discovery of methods of preserving for future consumption fish that cannot be disposed of just when it is caught; (3) the education of the public to use more freely the large supplies of excellent fish food that are available at our very doors.

Fishesare the most primitive vertebrate, i.e. backboned, creatures known. All reptiles, birds, and animals have gradually evolved from fish-like ancestors by a series of age-long processes, the stages of which are recorded in fossilized remains that are found in various rock strata throughout the world. A fish lives exclusively in water. It has no lungs, but extracts oxygen from the water as it passes over the surface of its gills. Instead of limbs, it has fins, with which it balances itself and propels itself through the water. Its skin is either bare, e.g. the cat fish, or is covered with scales, e.g. the herring, or with bony plates, e.g. the sturgeon. The skin of certain sharks is studded with minute teeth and produces, when cured, the well-known shagreen leather. In nearly all cases the skin of fishes is liberally supplied with small glands which constantly produce a lubricating mucus. This mucus greatly reduces friction between the fish and the water through which it moves.

The body of a fish is adapted to move swiftly and smoothly through the water; it is shaped more or less like a torpedo, but this form is greatly modified in different species. Certain species of fish living at the bottom of the sea, for example skates and rays, have become flattened, as though by a pressure applied vertically downwards. Others, for example plaice, flounder, sole, appear to have been flattened sideways. In the various members of the eel family, the body is greatly elongated.

Fig. 1

The body of a fish is generally coloured and markedin such a way that it becomes practically invisible when seen from above or below, the under-surface being silvery white, and the upper surface generally olive or blackish-green. Sometimes, as in the mackerel, the upper surface is mottled, resembling rippled water.

Most small fish in ponds and streams reflect their surroundings so well, and are coloured and marked in such a way, that they are almost invisible to the large fish, for example pike, that prey upon them. Generally, they reveal their presence by the flash of light reflected from above by their scales, as they turn suddenly to snap at a morsel of food. In the same way, many predatory fish, e.g. the angler fish, resemble their surroundings so closely that the fish for which they are lying in wait swim within easy reach of them without perceiving their danger. Many fishes, particularly in tropical waters, are remarkable for their bright and gorgeous colouring. It is impossible to preserve these colours in their natural brightness after the fish have been taken from the water, but amongst the brightly coloured corals, and anemones and seaweeds, in the crystal clear water of their natural environment, they flit like gorgeous tropical birds in a tropical forest.

Distribution.Fishes are found in practically every ocean, lake and river in the world, with a few notable exceptions, such as the Dead Sea, in which the concentration of salt is too high. They appear to exist at all depths of water, and have been found in the sea as deep down as 2,720 fathoms. Fish living at this depth generally possess enormous mouths, long, attenuated, soft bodies, and are equipped with highly developed phosphorescent organs.

The distribution of a particular species appears to depend upon the salinity of the water, the temperature of the water, the kind and quantity of food availableand the prevailing intensity of sunlight. It is possible to divide fish into four well-defined groups, according to the salinity of the water in which they are found: (1) Marine fish: those that live always in the sea, for example herring, haddock, shark. (2) Fresh-water fish: those that live always in fresh water, for example carp, trout, pike. (3) Many fish live in brackish water, and appear to be able to accommodate themselves easily to considerable changes in salinity, e.g. sticklebacks, gobies, grey mullets and blennies. Such species naturally are widely distributed; thus, a particular kind of grey mullet (Mugil capito) is found without any appreciable difference in form on nearly every coast of the Atlantic Ocean. (4) The fourth group of fish are migratory. Some species, for example salmon and shad, live and develop in salt water, but ascend rivers to spawn, i.e. to lay their eggs, in fresh water. Others, such as eels and certain pleuronectids, for example the flounder, live and develop in fresh water, and descend rivers to the sea to spawn. Many fresh water fish, e.g. trout, forsake the large streams in the spring and ascend small brooks, where the young can be reared in greater safety.

Of these different groups or species, the marine fishes are industrially by far the most important, for at least two-thirds of all the fish in the world live in the sea, and the capture of these sea-fish in enormous quantities constitutes the fishing industry, with which we are concerned.

The different species of marine fishes can be divided into three well-marked groups, according to their habits and habitats.

Fig. 2COD(Gadus morrhua)Length up to 5 ft.; usually caught at about 3 ft.Food.—Small crustaceans, molluscs, and young fish.Range.—North of Norway and Iceland to the Bay of Biscay, and from Greenland to New York.

Fig. 2COD(Gadus morrhua)

Length up to 5 ft.; usually caught at about 3 ft.

Food.—Small crustaceans, molluscs, and young fish.

Range.—North of Norway and Iceland to the Bay of Biscay, and from Greenland to New York.

(1) There are the true deep-sea fishes that live at the bottom of the sea, for example cod, haddock, plaice, sole. These are called “demersal” fish. Fish, likebirds, inhabit a medium that is continuous throughout the world. A glance at the map of the world will show that the three great oceans—Atlantic, Indian and Pacific—are united in the southern hemisphere. In Tertiary times, it is practically certain that the Pacific and the Atlantic oceans were also united at Darien, and that the Mediterranean was united with the Red Sea. Apart, therefore, from differences in local conditions, for example of temperature and food supply, there is practically no obstacle to the world-wide distribution of any particular species of fish. At the bottom of the sea, the temperature, the food supply, and the general conditions of life are singularly uniform all over the world, consequently there are no barriers at all to the dispersion of demersal fish, and we find various species widely distributed in all seas. Demersal fish, on the whole, are more primitive in type than those that live nearer the surface. They have well-developed senses of touch and smell by means of which they hunt for their food. They differ markedly in structure and shape from surface or shallow-water fish, their bodies being designed to resist the greater pressure of deep water. The body is generally lean and is enclosed by a wall of muscular fibre. Shallow-water fish, if introduced into deep water, would be crushed inward by the pressure. Similarly, the deep-living, demersal fish are unable to accommodate themselves to shallow water and, if placed in it, soon become unhealthy. A cod floats helplessly on its side when placed in shallow water, owing to the dilatation of its swimming bladder. If the bladder is pricked it collapses, and the fish is able to regain an upright position. This is done when cod and other similar demersal fish are kept alive in sea-water tanks on board ship, to be delivered to the markets alive. In Denmark, fish are delivered alive to the shops. When fishes fromgreat depths are brought to the surface, their bodies break into pieces owing to the reduced external pressure, the scales start from their skin and the eyes from their sockets.

There are two distinct types of demersal fish: the “round” and the “flat.” The body of a round fish is more or less circular in cross-section, for example cod, while that of a flat fish is flattened, for example sole, ray.

The most important edible demersal fish can be classified as follows—

(a) TheGadidae—related to the cod.

Cod—inhabits northern waters, notably the North of Britain, Iceland and Newfoundland.Ling—inhabits northern waters: West of Scotland and Ireland, and North towards Iceland and Newfoundland.Haddock—inhabits northern waters. Nearly half the total catch is obtained in the North Sea, from the White Sea to the Bay of Biscay.Whiting—found in great numbers in the North Sea. It is more coastal than the cod or haddock.Hake—found from Norway to the Mediterranean. The greater part of the catch is obtained off the south-west of Ireland. Hake is also caught off Morocco and in the Bay of Biscay.(b) ThePleuronectidae—related to the plaice and sole.Sole—a shallow-water fish, common in the Irish Sea, and particularly abundant in southern waters down to Morocco.Plaice—inhabits northern waters—all round Britain and Iceland.Flounder—inhabits estuaries, for example, of the North Sea and the Baltic.Halibut—inhabits northern waters. It attains a large size, six feet or more.

Cod—inhabits northern waters, notably the North of Britain, Iceland and Newfoundland.

Ling—inhabits northern waters: West of Scotland and Ireland, and North towards Iceland and Newfoundland.

Haddock—inhabits northern waters. Nearly half the total catch is obtained in the North Sea, from the White Sea to the Bay of Biscay.

Whiting—found in great numbers in the North Sea. It is more coastal than the cod or haddock.

Hake—found from Norway to the Mediterranean. The greater part of the catch is obtained off the south-west of Ireland. Hake is also caught off Morocco and in the Bay of Biscay.

(b) ThePleuronectidae—related to the plaice and sole.

Sole—a shallow-water fish, common in the Irish Sea, and particularly abundant in southern waters down to Morocco.

Plaice—inhabits northern waters—all round Britain and Iceland.

Flounder—inhabits estuaries, for example, of the North Sea and the Baltic.

Halibut—inhabits northern waters. It attains a large size, six feet or more.

Fig. 3LEMON SOLE (Pleuronectes microcephalus)Length up to 16 ins.Food.—Small crustaceans and worms.Range.—From North of Europe to the Bay of Biscay.

Fig. 3LEMON SOLE (Pleuronectes microcephalus)

Length up to 16 ins.Food.—Small crustaceans and worms.Range.—From North of Europe to the Bay of Biscay.

Fig. 4SKATE (Raia batis)Length up to 7 ft.Food.—Crustaceans and molluscs, and fish.Range.—Round the British Isles and along the coast of Western Europe.

Fig. 4SKATE (Raia batis)

Length up to 7 ft.Food.—Crustaceans and molluscs, and fish.Range.—Round the British Isles and along the coast of Western Europe.

Turbot—not very abundant. It inhabits the deeper parts of the North Sea.Brill—inhabits southern waters, and is fairly abundant.

Turbot—not very abundant. It inhabits the deeper parts of the North Sea.

Brill—inhabits southern waters, and is fairly abundant.

Skates and rays—found all round Britain, more particularly the Western area of the English channel.

(2) The various species of fish that inhabit the surface waters of the sea are called “pelagic.” They include the herring, mackerel, tunny, flying fish, sword fish, and many sharks, also various marine mammals, such as whales, grampuses, porpoises, dolphins. Amongst pelagic fish are included some of the smallest (plankton) as well as some of the largest (whales) of all living creatures. Pelagic fish pass their whole life swimming at or near the surface. They enter the shallow water offshore only for prey or, in some cases, periodically to spawn. The majority spawn in the open sea, far from land. Unlike demersal fishes, the distribution of the different species of pelagic fishes depends very much upon local conditions of light, water temperature, and the character and quantity of food available. They do not hunt their food individually to the same extent as demersal fishes, but generally filter it from the water as it passes through their gill-openings. Although not so widely dispersed as demersal fish, they are, in favourable circumstances, dispersed over large areas by swimming and by ocean currents.

All pelagic fish are “round.” With the exception of the mackerel, the important edible pelagic fishes belong to the herring family, and are known as the Clupeidae. They include—

Herring—found from the White Sea to the Bay of Biscay. It is the most abundant of all food fishes.

Sprat—found from the North of Europe to the Mediterranean.Pilchard—ranges from the English Channel to Madeira and the Mediterranean. Skipper “sardines” are young herring, pilchard, and brisling.There is also—Mackerel—found from the North Sea to Madeira and the Mediterranean.

Sprat—found from the North of Europe to the Mediterranean.

Pilchard—ranges from the English Channel to Madeira and the Mediterranean. Skipper “sardines” are young herring, pilchard, and brisling.

There is also—

Mackerel—found from the North Sea to Madeira and the Mediterranean.

(3) The shallow-water of the seashore is inhabited by certain animals (shellfish) not found elsewhere, including various mollusca, e.g. mussel, cockle, oyster and periwinkle, and crustacea, e.g. lobster, crab, prawn, shrimp. In addition to these, there are various species of immature offshore fish, e.g. plaice and dabs. The inhabitants of this shallow, coastal water are called “littoral” fish. The distribution of such littoral fish depends not only upon the water temperature and the amount of light, but also upon the character of the shore—whether it is rocky, or soft and sandy—and more especially upon the animal and vegetable products of the adjacent land, e.g. plants, seaweed, worms. Littoral fish do not swim very far, but become scattered inadvertently over considerable distances by currents and other mechanical means.

Fig. 5HERRING(Clupea harengus)Length slightly above 12 ins.Food.—Plankton (copepoda).Range.—From the White Sea to the Bay of Biscay.

Fig. 5HERRING(Clupea harengus)

Length slightly above 12 ins.Food.—Plankton (copepoda).Range.—From the White Sea to the Bay of Biscay.

Certain kinds of shellfish, for example oysters, mussels, cockles, live in the sand or attached to the stones or seaweed on the seashore, generally between high and low watermarks. They obtain their food from the water as it streams over their gills. They require adequate room for growth and development, and constant irrigation by water containing sufficient floating food. When mussel beds or oyster beds become overcrowded, the fish are ill-nourished, their health is impaired and their growth is arrested. It has been shown that, if they are transferred to new beds, their condition rapidly improvesand ultimately they increase considerably in size. All edible shellfish need systematic care and attention. Their cultivation by man affords the simplest instance of an attempt at a systematic aquiculture.

Food.The surface water of the sea abounds in minute forms of vegetable and animal life. This vast floating population of microscopic organisms is called the “plankton.” Just as man and all land animals depend ultimately for their food supply upon grass and other green-leaved plants which, under the influence of sunlight, are able to transform the inorganic constituents of the atmosphere and the soil into organic foodstuffs—albumen, fat, carbohydrates—so the minute unicellular marine plants of the plankton are able, under the influence of sunlight, to convert the inorganic constituents of their environment into fat, albumen and carbohydrate. Upon these minute organisms, therefore, directly or indirectly, all marine life depends.

In addition to these minute plants, the plankton contains nearly all forms of marine life at some stage or other of their life history. Fish are only found in it as eggs, or larvae. Crustacea of all kinds are present, and form one of its most important constituents. Crabs and lobsters spend their larval, free-swimming career among the plankton, until they reach the adult stage and settle down to the bottom. Various minute crustacea, known as “Copepoda” (lit., oar-footed) spend the whole of their lives drifting about in the surface water. They occur in incredibly large numbers, and are the most abundant of all forms of marine life. These copepoda form the main source of the food of pelagic fish, such as the herring, mackerel and sprat.

The larvae of the edible molluscs, oyster, mussel, cockle, develop in the warm surface water until they settle to the bottom and begin their adult life.

There are also many larval forms of marine worms and jellyfish, and many kinds of microscopic, unicellular organisms, some of which are vegetable and others are clearly animal. The chief animal forms belong either to the Infusoria, the Foraminifera or the Radiolaria. The shells of the two latter forms accumulate at the bottom of the sea, producing the deposits known as the Globigerina and Radiolarian oozes. In this way, chalk deposits were formed in primitive times.

The most important vegetable planktonic organisms are the Diatoms. Their accumulated shells form important deep-sea deposits.

The numerous varieties of planktonic life can thus be divided into two groups: those minute animal and vegetable organisms that pass the whole of their existence at the surface of the sea—the true constituents of plankton all the year round—and the eggs and larvae of many species of fish that are found among the plankton only at certain times of the year—notably in spring and summer.

The quantity of organic food substances such as albumen, fat and carbohydrate, that is contained in the plankton produced annually by a given area of the sea, has been compared with the quantity of such substances produced by a similar area of land in crops such as pasture, hay, lupine and peas. In this way, it has been estimated that the productivity of the sea is about 20 per cent less than that of average land.

PLANKTON: LARVAE1. Crab zoea; 2. Fish egg; 3. Sea Urchin pluteus; 4. Barnacle nauplius; 5. Fish larva; 6. Mussel larva; 7. Copepod nauplius; 8. Worm larva.

PLANKTON: UNICELLULAR ORGANISMS1, 2, 3, 7, 10, 11, 12, 13, 16, 17, 18. Diatoms; 4, 5, 7, 9, Peridinians 8. An Algal spore; 14. Noctiluca; 15. A Radiolarian.Fig. 6

Unlike that of the land, the productivity of the sea is greater in colder latitudes than in the tropics. This somewhat unexpected fact is attributable to the action of denitrifying bacteria which, flourishing more readily in warm, tropical waters, effectively reduce the amount of available nitrogen compounds in the water. In colder waters, denitrifying bacteria are less active, and nitratesand nitrites are available in larger quantities for the nourishment of the plankton.

All the great fisheries of the world are prosecuted in cold or temperate seas; as examples of this we have the Banks of Newfoundland, the cod fisheries of Norway, and the great trawling grounds of the North Sea and the North Atlantic.

All fish, during the larval stage of their development, feed first upon the contents of the yolk sac which, when they are hatched, is attached to their ventral surface. When the yolk is absorbed, the larvae feed upon the microscopic plankton that abound in the water on every side. The surface water, with its warm temperature, high plankton content and sunlight, forms an ideal nursery for the very young fish of all species. Demersal fish, as they complete the larval stage of their development and descend into deeper water, have to rely for their food either upon the various species of young shellfish and crustacea that drop from the surface water as they develop, or hunt for their food amongst the small fish, mollusca, crustacea, worms and seaweeds of the sea-bottom. Plaice feed chiefly upon cockles and other mollusca, which in their turn feed upon diatoms. The cod is almost omnivorous, greedily devouring small fish, crustacea, worms or mollusca; its favourite food, however, is shrimps and prawns. These, in their turn, feed upon smaller invertebrates, for example small jellyfish and larval molluscs, and these upon microscopic plankton.

Pelagic fish, herrings and mackerel, feed almost entirely upon the larger plankton, mainly copepoda (small, shrimp-like crustacea). These may be present in the surface water in enormous quantities at certain times. In many cases, shoals of herring or mackerel probably follow special swarms of copepoda. Mackerel also feed upon young fish, hermit crabs, and prawns.

With a few notable exceptions, the various species of demersal fish feed upon smaller fish. Thus—

The hake, normally a deep-water fish, ventures inshore in pursuit of herrings, pilchards, mackerel.

The ling, turbot, brill, dog fish live entirely upon small fish. The dog fish swarms on certain fishing grounds and is often a serious pest to the drift-net fishermen, destroying their nets as well as the fish that are attached to them.

The whiting, like the cod, feeds upon small fish, and upon crustacea and mollusca.

The food of the haddock consists of mollusca, crustacea and marine worms, etc.

The sole lives on small crustacea, for example shrimps, and marine worms.

Skates and rays feed upon mollusca and crustacea.

Most shellfish live in shallow water and feed upon the plankton.

The methods by which fish obtain their food differ greatly according to the species of the fish. Pelagic fish, e.g. herring and mackerel, sprat and pilchard, obtain their food almost automatically as they swim open-mouthed through the water in which it abounds. These direct plankton-feeders possess comb-like structures—the gill-rakers—attached behind the gill openings, and as the food-bearing water streams through the mouth and gill openings of the fish, these structures strain the food from it. The fish licks the plankton from its gill-rakers with its tongue and swallows it.

Many pelagic fish, e.g. carp, trout, salmon, look for their food while swimming through the well-lighted surface water.

Demersal fish—flat fish, cod, haddock, etc.—seek their food by scent and touch. The cod possesses a barbel attached to its chin, by means of which it feels for its food.

The Angler or Devil fish is a curious creature, from three to four feet long, and appearing to consist almost entirely of head. It has a large mouth, and teeth that are hinged so as to admit food, but prevent it from escaping. The devil fish has a long feeler on the top of its head, terminating in a tassel which, moved by the water, attracts the attention of small fish and lures them to their fate. This tassel is a sensory organ and, when it is touched by the small fish, the angler fish snaps upwards with unerring aim at a point immediately in advance of the tassel.

The dog fish seeks its food exclusively by scent. If its sense of smell be destroyed, it ceases to feed spontaneously.

The sole also seeks its food by smell. It is quite unable to recognize a worm by sight or touch, even when hung just above its head, but feels aimlessly over the ground seeking it by smell.

Reproduction.Fish are male and female and, with few exceptions, reproduce their kind by laying eggs. The number of eggs laid by an individual female fish during a single spawning varies greatly, according to the species. The average number of eggs spawned by a single female fish in the course of one season, is—

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