The Zoologist/4th series, vol 1 (1897)/Issue 675/Our Economic Sea Fishes

by James Murie

 

THE ZOOLOGIST

 

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No. 675.— September, 1897.

 

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OUR ECONOMIC SEA FISHES.

By Dr. James Murie,
Member of the Kent and Essex Sea Fisheries District Committee.

 

It would seem to be a racial peculiarity of the British community concerning those matters in which ultimately they attain preeminence, that they should, more often than otherwise, only be arrived at through a series of blundering experiences. Expressed otherwise, the English slow-to-move habit and perfect do-as-you-like freedom beget a tendency to let things move in their old circle until personal interests of a few spread to the many. Then follow surging and activity, seldom resting until leeway is made up, and they are abreast of, perchance push beyond, the nations started earlier and more systematically disciplined in the given field. Unfortunately too many examples might be cited, particularly in the political sphere, as well as in those of literature, art and science. Speaking broadly, British efforts, as a rule, have sprung from private individual exertion, the Government only falling in perforce, whereas Continental nations in the main reverse the process.

Our economic Sea Fish and the associated industries are instances in point. Seemingly it has taken a long time to realize and arrive at the conclusion how close is the connection between these and Ichthyology.

When her Majesty ascended the throne, and indeed almost for half her reign, the Cuvierian and Müllerian classifications of Fish, perhaps with some few exceptions, were alone regarded in the light of science, while study of the useful groups of Sea Fish were little better than meagrely referred to or looked at rather in the light of a trade subject. How could it be otherwise when the genial but distinguished Yarrell was shunted by the Royal Society as only a tradesman and pseudo-scientist?

Yet, after all, though late in the field, it looks as if Fish economy is bound to revolutionize some of the older doctrines current among Ichthyologists. It is a case of evolution in science; the microscope and embryology have helped Fishery questions over the stile, so that practical or economic Ichthyology—namely, the life-history of our Food Fishes—is the new departure of this branch of Zoology.

There are two circumstances which stand out in relief in the chronicles of commercial Sea Fish. One, the oft-recurring scares as to the decline and probable destruction of the British Fisheries, with repeated Parliamentary enactments thereon; the other, the antagonism of the fishermen and ichthyologists.

What took place, say, in the sixteenth or seventeenth centuries onwards, is certainly reproduced with but slight variation up to the present date. Forsooth, there has been no want of legislation; the old Statute Books teem with it. For example:—Catch and traffic in Herring; preservation of Sea Fish spawn and fry; width of mesh of nets; regulations for Pilchard fishery; grievances of Lowestoft versus Yarmouth; encouragement of British Fisheries; relations with foreigners re Fish and Fishing, &c, &c.—nearly all subjects worrying the Sea Fisheries Boards of to-day as much as they did Parliaments in the reigns of the Henrys, Elizabeth, and the Georges.

The fact is, as in every other trade, that of fishing is liable to fluctuations; but the problem in this case and the remedies are far more intricate than in an ordinary business. Even the methods of science, as of political economists, hitherto have failed to unravel the laws of, still less to point out modes of relief to, the fishing industries, though there is a dawn, it is to be hoped, of better things in store. Wherefore non-agreement between fishermen and ichthyologists is easier accounted for. Why inquire about common things, our catch, or where a particular sort of fish is found, &c.? It cannot mean business, but may only hide some design probably against the fishers' interests, therefore interrogators must be baffled. In illustration I may mention that only a dozen years or so ago the streets of St. Andrews witnessed some high jinks. Amidst sounds of merriment an effigy of the Natural History Professor was paraded about and ultimately burnt on the sands. The University don had dared to announce the heretical notion that certain sea-fish spawn floated; they, the fishermen, knew better, and further concluded some evil intention lay in the Trawling Commission. The real victim enjoyed the joke, and went out to witness his incineration. Ask those fishermen to-day regarding the occurrence; they smile at the "lark," but swear by the Professor.

Among the Statutes of Edward III. were those relating to Herring, since which there have been a shower of others, besides Commissions on the same fish. Indeed it has mainly been through this shoal-roamer, the staple at least of the northern part of the kingdom, that in this country the naturalist has been called in as arbitrator—exactitude versus loose opinion—and Dr. Knox, Harry Goodsir, and Professors Allman and Huxley have acted as the thin end of the wedge.

In the issue of Couch's 'British Fishes' (1862–64) the author announces as his intention:—"It has been deemed of special importance to give with as much precision as possible an account of the characteristic habits of each species.... with frequent communications from practical fishermen of great intelligence."

About the same time Bertram, in his 'Harvest of the Sea,' in a prefatory note says he believes his is the "first work in which an attempt has been made to bring before the public in one view the present position and future prospects of the Food Fisheries of Great Britain."

What doubtless in some measure helped in due season to modify the attitude and hasten the change of British scientific men towards Fishery questions was the Norwegian Prof. Sars' discovery (1862) of the floating (pelagic) nature of the Cod's ova as contradistinguished to the sunken (demersal) nature of those of the Herring and presumably of other fishes.

It is due though to Frank Buckland to accentuate the circumstance that for a number of years, in and out of season as the case might be, he kept drumming into the ears of the public, in his own humorous but vigorous fashion, the importance and necessity of Sea-fishery investigations. His communications more often appeared in 'The Field' and 'Land and Water,' and occasionally from their literary style suggested a smack of the charlatan. But the best evidence of the earnestness and worth of the man was the devotion to his Fish-cultural Museum at South Kensington, ultimately endowed and bequeathed by him to the nation.

A wholesome impetus was also given to fish studies by F.M. Balfour's Monograph on Elasmobranchs, quickly succeeded by his Treatise on Comparative Embryology; Buckland and Walpole's Government Report 'On Sea Fisheries of England and Wales' (1879); Dr. Günther's 'Study of Fishes'; and Dr. Day's 'British Fishes,' but especially Buckland's Appendices (II.–IV.) of Report, pressed home the subject of our Economic Sea Fish.

The fishing industry itself (chiefly Grimsby and Hull trawlers), on account of the moot question of deterioration of the Sea Fisheries, and supposed relation of this to the capture and sale of immature fish, resolved itself into a National Sea Fisheries Protection Association, with affiliated branches throughout the kingdom. Their conferences and public agitation no doubt had considerable influence in after-movements of corporate bodies and the Government.

At this juncture came the Norwich and Edinburgh, followed by the London International Fisheries Exhibition of 1883, with its abundance of foreign and American element; the latter even in certain sections of food-fish and appliances far outstripping the English collections. Much of the Exhibition literature and conferences was of a practical kind, widening yet urging the current of British Fish industry in the new direction.

Still one thing was manifest, viz. "That our knowledge of the habits, time, and place of spawning, food peculiarities of the young, migrations, &c, of the fish which form the basis of British fisheries is lamentably deficient, and that without further knowledge any legislation or attempts to improve our fisheries by better modes of fishing, or protection, or culture, must be dangerous and indeed unreasonable."

But the echoes of the consensus of opinion at the Fisheries Conferences, as above quoted, had hardly died away ere the said defects were being amended. Complaints of the line and driftnet fishermen stirred the Government to a commission of inquiry on the trawl-net and beam-trawl fishery. Its chairman (the late Earl of Dalhousie), supported by Prof. Huxley and Mr. Brady (Inspectors of English and Irish Fisheries), and colleagues were all experienced and energetic. Prof. Mcintosh fortunately was appointed "to undertake a series of observations upon the results of the use of the beam trawl-net, and upon the distribution of the food-fishes taken by trawlers upon the grounds which they frequent at different seasons of the year." Thus reaching a climax, one may say, for from the Report of this Commission has sprung that activity and fusion of the interests of science and fish industries in Britain.

The Fishery Board for Scotland (reconstituted from the old White Herring Fishery Board) started into new life. Coincidently and at short intervals thereafter there arose Marine Laboratories, to wit, those of St. Andrews, Granton, Plymouth, Liverpool (Biol. Soc), and others, and, later on, a Sea-fish Hatchery at Dunbar.

Whilst the Government could not see their way to carry out the recommendations of the 1883 Commission in extenso, they yet adopted some of them with modifications, and departmental changes resulted. The Sea Fisheries Act of 1888, taken in connection with the creation of County Councils, was the means of introducing the Sea Fishery District Committees of England. With them, as in the instance of Lancashire, further activity took place in fishery problems, though many of them were already being solved through the active and practical efforts of the Scotch Fishery Board and the Marine Laboratories. In fact, ichthyological science had at length been brought in touch and amalgamated with the interests of the fishing communities themselves, and this partly by some of the County Council's Technical Instruction Committee's organizations.

In brief, then, the Victorian Era, inasmuch as commercial Sea Fish and fisheries' lore are concerned, commenced with a distinct paucity of knowledge of the life-histories and habits of the species. Yarrell's 'British Fishes' may be taken as the starting point, adding Parnell's 'Forth Fishes' as a twin sample of their economy and the local faunas then extant. The Jubilee goal or opposite extreme presents us with Cunningham's 'Marketable Fishes' and Mcintosh and Masterman's 'Food Fishes.' For the first four decades the progress was slow. A few years of interregnum with indications of change of front succeeded. Lastly, fully another decade of rapid issue of quite a different order of fish literature, and information as to their everyday habits, breeding, &c.

I have avoided discussing, except by mere incidental reference, what influence other countries may have exerted in the production of change in our own. As a matter of fact this has been considerable. To continental and American authorities and their governmental action we are primarily indebted for many important investigations and movements in fishery questions. The Cod and Herring breeding and migration, the surface fauna, sea-fish hatching and marine laboratories, besides other matters, have often received their earlier attention, and we in this country, lagging behind, have at last only too gladly availed ourselves of their priority. Our haphazard mode and mere outcome of individual personal interest have obliged us, one is almost ashamed to say, to follow the stranger's leading. That hurry-up of the last decade, as of old, has been a matter of necessity to keep in line with the advance guard. It may be questionable if we are not yet the rear guard in some ways.

To whither we have arrived at in the study of our economic Sea Fishes is best made evident in the pages of the lately published volumes of Mcintosh^[1] and of Cunningham,^[2] respectively the product of the St. Andrews (Gatty) and of the Plymouth Marine Laboratories. The authors, while having been active workers themselves in the subjects under consideration, yet avow that their form of book production is but intended as a summary of the most recent and important scientific investigations, otherwise scattered through many British and Foreign Transactions, journals, periodicals, &c.

The contents of the aforesaid Food Fish volumes are ostensibly identical, but their treatment somewhat dissimilar. That from St. Andrews is illustrated by twenty-one coloured plates containing some 250 figures, besides forty-five woodcuts distributed in the text. These represent the eggs, larval and post-larval conditions of the great bulk of our food-fishes. That from Plymouth has 159 woodcuts, and two maps of the fishing grounds of the British Islands and west coast of Europe. The authors freely acknowledge their indebtedness to the many workers of all countries. Besides other subsidiary matter the text deals with the pelagic fauna generally, egg development, and subsequent growth of the larvæ to adolescence onwards; but the major portion is devoted to the life-history of particular families and species of Sea Fish used for consumption. All the dry reading on synonymy and the opinions of the early classical or ichthyological writers are dispensed with. Both are excellent epitomes of the methods and results of modern research as adapted to the practical issue of fisheries questions.

No longer is the fish described from a shrivelled or spirit-preserved specimen. Rather is it now studied in the living condition in the aquarium in large tanks, or it is hunted out in its native haunts at all seasons, and frequently even in inclement weather there and then watched and examined in every stage as to age, condition, food, and surroundings. The eggs themselves are fertilized and hatched under the eye of the observer, and from the transparency of the pelagic ova, under the microscope and reagents, every change from fertilization to final hatching can be followed step by step with ease. Thereafter the post-larval changes and habits to adolescence are noted and compared with those of the adults at freedom in the sea.

While it could have been said with some show of propriety in the early eighties that none or very few indeed of our commercial sea-fishes' life-histories were known, now at least it may be affirmed that the great majority of them are tolerably well ascertained. For instance, of the Gadidæ, take the Cod as being that whose pelagic ova first attracted Sars' attention, and which have since undergone the close scrutiny of several able naturalists. It spawns from February till May, the female carrying from two to nine million ova. These diminutive glassy spheres, at first scarcely visible, float freely, and in still water rise to the surface. The embryo hatches about the eighth or tenth day. At first the larval Cod are impelled about helplessly, often the yolk-sac uppermost. These tiny fish have black transverse bars, giving them quite a characteristic appearance. In a week's time the yolk-sac is absorbed—the post-larval stage—and the barred pigmentation becomes tesselated or tartan-like. The future back and belly fins are originally continuous membranes. When about three weeks old the head becomes pigmented, while the body assumes more of a greenish yellow hue. Shortly after there is budding of ventral and separation of dorsal fins, and a tendency to longitudinal pigmentation of the body. When arrived at about an inch long or over, the fish has assumed quite an adult facies, with barbel and fins complete. From the rock-pools and upper water they descend among the shore algæ. By the late autumn they are four or five inches, and by the spring a foot long. A seaward migration then takes place, and in their third or fourth year they return in immense companies as full-grown Cod.

Sexual maturity, according to Holt, is when the Cod are from twenty-two inches to three feet long, though Mcintosh is inclined to deem twenty inches a fair average. Quite a variety of annelids, crustaceans, and fish form the Cod's diet; but it is a most voracious, indiscriminate feeder.

The embryology, post-larval up to the adult stages, of other members of the Cod family have in similar manner received assiduous attention. Besides the movements, the food and the everyday life of the fish themselves in their marine habitat have been carefully watched on all parts of the British coasts, both within (shorewise) and beyond the territorial limits. Thus a mass of evidence and information has accrued, practically instructive alike to fishermen and scientific seekers.

The young Ling undergoes remarkable transformation in colour and in curtailment of ventral fins, which in the early stage are relatively of enormous length. The eggs of the Torsk and Ling are distinguished by a great oil-globule, which renders them more conspicuous in the water than those of their allies. The Haddock, and to some extent the Whiting, keep to deep water offshore grounds till reaching five or six inches in length, when they take to swarming in the inshore and estuaries—in this respect the opposite of the ways of the Cod.

With regard to the Clupeidæ (Herring family), Mcintosh and Masterman say that:—"In the case of the four common Clupeoid species—the Herring, Sprat, Pilchard, and Anchovy—the most superficial examination of their eggs with the naked eye is sufficient to distinguish them. The opacity and thick adhesive membrane of the first, the translucence and delicate capsule of the second, the clear peri-vitelline space and oil-globule of the third, and the unique shape (ovoid) of the last are all characters readily recognizable without the assistance of the lens."

Size alone distinguishes the Gadoid eggs. The Herring's egg belongs to the sunken type (demersal), a feature not shared by its immediate family allies, nor of the Cod and flat-fish families; these groups embracing the chief economic British fishes. It is this very exceptional circumstance, together with the occasional eccentric periodic migratory habit of the fish itself, that has compelled the Government repeatedly to recognize the necessity for inquiry into the creature's ways, as a matter involving the nation's fisheries' welfare.

The fluctuations in the Herring fishery can scarcely yet be satisfactorily accounted for, though the hue and cry against trawling is met by the reply that the spawning areas, so far as is known, are not those usually frequented by the trawlers.

There is a slight excess of males among Herring. The female carries from 20,000 to 50,000 ova. Spawning time varies round the coast. Experiments instituted by Dr. Meyer, of Kiel, and corroborated by other observers, prove that temperature of the water materially influences the hatching process. Though seven to ten days is the normal period, cold may vary this to forty days, and pari passu the size of larvæ. When first hatched the larva is more advanced than in the Sprat, a buoyant egg-form. The larval Herring has a biggish head, attenuated colourless body, and the gut passes to proximal tail-end; a broad fin-membrane extends posteriorly from yolk-sac uniformly over back and belly. In the early post-larval stages growth is lengthwise, thickening of body not increasing in the same ratio. There is yet absence of scales or silvery sheen. Later on, however, fins differentiate, the anus acquires a more forward position, the body deepens, fine pigmentation appears, and shortly afterwards the silvery hue commences—the Whitebait stage.

Mcintosh and Masterman thus summarize the early Herring:—"The young larva, hatched at from 5 mm. to 7 mm. in length, lives near the bottom till about 10 mm. is attained by a rapid increase in length. The attenuated post-larval Herring then migrates upwards through the mid-water to the surface, the midwater stage lasting from about 10 mm. to 23-24 mm., and the surface stage from 24 mm. to 27-28 mm. [roundly speaking, one inch or thereabouts], when a movement shorewards takes place, and the littoral habit is acquired."

Their further increment and subsequent erratic movements are a more tangled skein to unravel. Growth and maturation are complicated and confused by a double spawning period. Data give a length of three inches the first twelvemonth, to five inches the second year, and to eight or nine inches the third year, when sexual maturity is attained; but British and foreign observers are not quite in unanimity thereon. It would appear though that in the case of the Baltic as well as British Herring there are two marked spawning seasons, the so-called winter and summer Herrings. The same Herrings, however, do not spawn twice annually, the summer and winter stock being races apart, whose spawning localities essentially differ. Winter spawners frequent inshore brackish waters, whereas summer spawners are more strictly sea-dwellers, coming near the coast, but not into estuaries at spawning season. The Clyde, Forth, and Plymouth Herring are winter, the North Sea group summer breeders. The former estuarine fish come and go within a limited area, the latter offshore have a wider sea migration. In both cases, though, it is a see-saw towards and away from the coast, the so-called summer Herring spawning in deeper water further distant from land.

The supposed mystery of the fish returning to their own special grounds, Cunningham thinks is due to their habit of herding in shoals. Temperature and food drive the fry up an estuary, and there as they grow, meeting older brethren, associate and accompany them back to the sea-spawning ground.

Of other Clupeoids, it is singular that the Sprat is much more used as an article of diet in England than in Scotland, though to be found equally abundant in both. According to Mcintosh Sprats spawn well up reaches in estuaries, but Cunningham avers that spawning occurs in the deep water. From such data it may be inferred that they have a summer and winter spawning season in different areas like the Herring. Yet there are manifest physical differences in their entire career. In the Sprat the female but carries 5400 ova; the eggs are pelagic, though inclining ground wards, and they are markedly reticulate; incubation short, three to four days; a slower larval and post-larval development; at the early stage mouth closed and absence of pigment in eyes and body generally; transformation at 1¼ in., about a year old 2 in. or 3 in., and the sexually mature stage 4 in. to 4½ in. long, viz. two years of age.

The Pilchard essentially is only a south-west British form, and its winter home the English Channel. They are rarely caught in the gravid condition; their ova count some 60,000. They spawn far off shore. The egg is typical of those that float, but unique in possessing a large egg-membrane space, a segmented yolk, and an oil-globule—these three characters not being united in Clupeoids or other families. Incubation takes four or five days. The early larva is one-seventh of an inch long, the yolk still large, the mouth closed, and pigmentation sparse. At three days the mouth develops, at five days they feed, are one-fifth of an inch long, and the yolk absorbed. At the Sardine stage, four inches or over long, they are about one year old, and they are sexually mature at two years of age, then being eight or nine inches long. The Anchovy is also chiefly a southern British form, and for it there is no regular fishery; but that of Holland, on the contrary, is very valuable. Cunningham infers that the Dutch Anchovies retreat in October towards the English Channel, the same again migrating north in the spring to spawn. Their sausage-shaped egg is quite exceptional among floating eggs. The Shads have the Salmon habit of running right into fresh-water streams, where they spawn. They are less a food product in this country than in America, where Shad hatcheries are quite in vogue.

The Pleuronectidæ, or flat-fishes, nowadays holds a high position in the English fish-trade. Not being used in the salted condition, formerly their consumption was restricted coastwise; but after the introduction of trawling into the North Sea, of steam, and especially railways, with the use of ice, they regularly found their way to interior markets in quantity in the fresh condition. Herring and Cod of yore were the grand staple of fish-trade in this country and the Continent; yea, much rivalry and many a pretty local and international quarrel arose thereon. Even yet witness the Newfoundland grievance.

There are quite a number of species of Pleuronectid food-fish in household use. If not individually of the most intrinsic value, yet collectively the Plaice probably heads the list in mercantile superiority. Its life-history consequently has received due attention. Broadly speaking, the old fish are quite offshore dwellers, whereas the young are estuarine, bay and sandy shore frequenters. The cycle pursued is thus traced. The ovarium may contain from 250,000 to double that number, the spawning process being by driblets. It is the earliest spawner of the flatfish, commencing in January or prior to that date. The egg, of large dimensions, is pelagic, with striated capsule and minus oil-globule. Incubation varies according to temperature, &c. At St. Andrews, in April, eight or nine days; at Dunbar, in January, sixteen to eighteen days; at Granton, in(?), twenty-seven days. The newly-hatched Plaice resemble the Flounder and Dab, but are larger, viz. about one-fifth of an inch. The mouth is closed, the gut opens immediately behind the yolk, pigmentation is diffuse, the eyes are on each side of a deep, vertically compressed body, and there are broad marginal fin-membranes. From larval to post-larval stage there is a gradual descent from surface to mid-water, and then to bottom. Then turning upon their left side, this loses its pigment by absence of light, whilst the left eye begins to pass towards the right one. Meantime the young fishes by degrees travel shorewards. When verging on half an inch long the body broadens, the eye has got well towards the right, the dorsal fin has advanced to its hinder border, the lateral line looms up, and brown pigment is diffused throughout the upper or right surface of the fish. Growth meanwhile proceeds apace. When a couple of months are over it may be about one inch long, at eight months three inches, a year old four and a half inches, when sixteen to eighteen months reaching about six inches long. Towards the end of second year it averages ten inches, and in the spring of third year it arrives at sexual maturity, say, twelve to fifteen inches; though growth continues thereafter, Plaice of thirty inches being recorded. There appears to be a northern large and southern small breed of Plaice, a circumstance confusing in legislating on size limits for market purposes. Experiments by the Scotch Fishery Board officials in St. Andrew's Bay and Firth of Forth prove that the young Plaice travel in definite directions. From seaward where let free a semi-rotary course was followed by south shore westerly, then by north shore easterly, towards their spawning grounds; many specimens spent a long time in traversing the route. This tallies with Holt's observations on the opposite shore of the North Sea. There the currents trend to the Heligoland bight, the ova floating in that direction, where the post-larval fish spend a period, again to return to the offshore spawning areas. Their chief food is molluscs of various kinds and marine worms.

The Sole has had a finely illustrated monograph devoted to it by Cunningham (Mar. Biol. Assoc). In this its embryology, adult structure, and economy are fully treated, and various species of Solea meet descriptive notice. The egg, very characteristic, has a ring of minute oil-drops and a segmented yolk. Incubation lasts four to ten days. The larva is hardy and restless; the post-larval changes in the main resemble those of the Plaice. At nine months it is two and half inches, a year old six or seven inches, second year nine to eleven inches, and third year nine to fifteen inches long. There is a migratory movement analogous to the Plaice, but Soles seek the deep water during cold weather, and vice versâ. The Turbot, though not an abundant fish, would seem prolific, judging from its one to ten million ova. Eggs hatch in six or seven days. At their later stage these assume quite a red appearance, and this pigment coloration is a marked feature of the larva, though soon changing to orange hue. In the post-larval stage the head has a spine armature, which afterwards disappears. Few of the Turbot's pelagic ova are found either offshore or inshore. It spawns offshore, where the larval and post-larval stages are spent; in their later youth they disport themselves inshore, but when ten to eleven inches they again seek the deep water. Its predacious Herring-feeding habits keep it moving after these vagrant fish. The Brill spawns earlier than the Turbot, but their development and habits throughout closely resemble each other. The Brill is likewise a fish-eater, Sandeels, Sprats, and smaller members of the Cod tribe being its chief fare.

The Halibut, king of Pleuronectidæ in size, when about a foot long, are occasionally found shorewards, but the adults are quite deeper sea dwellers, and are fish and crustacean feeders. The Flounder, though closely allied to the Plaice, differs widely in habits and migration. It arrives early at maturity, and is exceptionally fecund. There is much disparity in the sexes, the females largest, the males most numerous. It is quite estuarine in habit, a mud, sandy shore lover; but it ascends and dwells in rivers quite to the fresh-water mark, though the adults migrate seaward to reproduce. The Dab has an exceedingly small egg; it is not a prolific fish, and the male is smaller than the female. They are not sexually mature till the third year, growth thereafter being slow.

Of other families of British food-fish, the Mackerel doubtless is most important, but unfortunately the chapter in its life-history is still wanting in several particulars. The Red Mullet is remarkable inasmuch as in the larva the "yolk-sac projects far beyond the front of the head, and the oil-globule is placed at the extreme end of the projecting portion," a feature, however, in part shared by the Comber or Smooth Serranus. The Bass, the Grey Mullet, the Skates and Rays (the poor man's food), and Conger and some others, are each and all of considerable consumption; but it is enough to say that modern students of piscine biology are at present trying hard to unravel that ancient mysterious puzzle, Whence the Eel and Conger?

 

The whole scope and essence of this new-born Food-fish study resolves itself into the elucidation of general laws applicable to the finny tribe. It is thought that by the aid and exactitude of modern scientific appliances and methods this may be attained, and the knowledge imparted to the fisher fraternity themselves. Towards such inquiry there is wide scope, for living things, physics, and variety of surroundings lend complexity. It is not easy then to gauge the respective influences and their values, and formulate laws accordingly. Hence where certain difficulties present themselves there is a loose tendency to phylogenetic speculation. This last may temporarily satisfy our ignorance, but yet is an unstable platform to rest on where practical issues are at stake.

Necessarily many of the researches now in progress appear superfluous or insignificant, but science abounds with instances of seeming trifles leading to unexpected beneficial results. It cannot be affirmed with absolute certainty that there has been material increase in British fisheries since the advent of the laboratory and out-of-door investigations. But there is no gainsaying the fact that a sound foundation has been laid for a study of their economy; witness Mcintosh and Cunningham's volumes aforesaid. Take, for example, investigations of embryotic and postlarval conditions: it is a long jump from 0 to over eighty species to be recorded.

The spawning grounds, the periods of spawning, and the varied lengths of the spawning process in different fish, are in many cases far better understood, whilst it is pretty well proved that temperature has a manifest effect on the duration of hatching, a fact established by Higginbotham (1850)^[3] in experiments on the Frog, and now shown likewise to be the case in fish-eggs. Migratory habits are gradually getting law-evolved. As to cases in point, there is that of the to-and-fro movement from offshore to inshore, and the reverse. Of a certainty it can now be said of some fish, that on hatching the larva and post-larva uniformly and gradually make for shore or shallow water, there to spend their young stage, to retreat again to deep water on becoming older, and this in a definite course. There is regular congregation and migration during spawning season, partial dispersion thereafter. Search for food assuredly induces wandering habit, and atmospheric changes drive to greater depths. The factors conducing to erratic wholesale emigration, or the sudden departure from a long frequented spot or area, each fish's particular enemies, and their diseases aside from effects of parasites, are still sub judice.

Probably there is no more promising field still requiring exploration on British shores than that of the surface organisms, and this is likely to yield substantial data to clear up several of the knotty fish problems. McIntosh kept a record for a year of those pelagic fauna found in St. Andrew's Bay, and the monthly variation is most interesting and instructive. He compares the whole to a spindle, the thick mass corresponding to May-July, therefrom tapering on either side to the ends=January. To these surface forms, as a whole (plants and animals), Hensen has applied the technical term "Plankton" (πλαγκτός, wandering).^[4] He believes the economical food yield of the ocean can be statistically determined by quantity. Without here questioning his theory, one doubted by Haeckel, it certainly is more obvious that there is an intimate interdependent relation between marine life and seasonal fish numbers. This through plants furnishing pabulum to invertebrates, and these again to piscine groups. To pursue the links in the chain further, the plant profusion is determined by meteorological conditions, and we have arrived at physical causes more within our ken, and probable after results determinable beforehand. Thus step by step are we likely to arrive at reasons for the annual gluts or dearths of fish, early or lateness of seasonal appearance, food migrations, &c. The more pressing or immediate interests of fisheries' industries, meanwhile, have not been lost sight of by the scientific inquirer. Much has already been accomplished towards ascertaining the limits of sexual maturity in both sexes, and the vexed questions of trawling and temporary closure of areas have received due attention. Into these I do not propose to enter other than by pointing out the assumption (a fashion revelled in by the younger biologists) that our fishing is producing a stunted race of flatfish(?).

The institution of Sea-fish Hatcheries, so extolled in America, is yet on its trial in this country. Opinions thereon are divided, the balance being rather in favour of those who maintain the Scotch verdict of "not proven." It is questionable whether the working of a hatchery could be made profitable or not. The weak point in the Dunbar hatchery is liberation only in the fry stage. To remedy this defect, what in contradistinction may be termed "nurseries" are suggested. In these, with larger enclosed areas under suitable more natural conditions, the fish could be retained until older and better able to avoid enemies when set free. From the foregoing statements it may be allowed that research has passed beyond probability, and a tangible result obtained, though still more is wanted ere rational legislation and full benefit accrue. To get this within reasonable time additional State aid seems necessary, for, as the nation generally is to benefit, it is not the rôle of private adventure.

We have four University Marine Biological centres. Port Erin (=Liverpool), with voluntary workers, does a fair share of investigation, chiefly, not exclusively, of a local character. The Lancashire County Council contribute towards sea fisheries and technical instruction, otherwise all is private energy. At Plymouth (=Oxford) the researches carried on are of a high standard. The Treasury grant £1000 a year, and the Fishmongers' and Drapers' Companies in round numbers £500 without equivalent. Other funds come from sale of specimens and admissions of public, &c. Most unfortunately this station carries a "white elephant," viz. a building of huge proportions and officials proportionate. This I strongly warned the originators to avoid, but Naples was the model taken, and my advice was disregarded, though now, I fear, discovered too late. It was started with a very large fund (£12,000), but it is to be regretted it suffers from the initial error. Milport (=Glasgow) heretofore has been modest in its aspirations and gratuitous in its labours, though it is advantageously situated towards the peculiarly deep salt-water lochs worthy of further study. St. Andrew's (=Gatty), the first started in Britain, has all along been hampered by paucity of means. For some time the Scotch Fishery Board allowed a slender annual donation (for their fisheries purposes—said donation now withdrawn); otherwise all its high-class work has been solely by private energy. Nevertheless for deeds accomplished she has worthily stood abreast of her more favoured southern rival. Lord Reay^[5] puts it in a nut-shell when he says: "There is one feature... of which I can speak without being specialist, and that is the extraordinary economy which has been practised."

With this Jubilee year, and the stock-taking of the Victorian Era, on comparing the mother with her daughter colonies, and with other nations whose fishing industries are relatively less than our own, it stands out that the British Government only lukewarmly responds to the science requirements of the most important national Sea Fish food question in its broad aspect. Hence the time has arrived, if we are to keep place in the race, when a further impetus might well be given to speed the good efforts in this direction. It behoves moreover that distribution of funds should be so judiciously spread that Universities' heart-burnings be moderated, withal stimulated.

 

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1. 'The Life Histories of the British Marine Food Fishes.' By Prof. W.C. Mcintosh and Asst. Prof. A.T. Masterman, University of St. Andrews. 8vo. London, 1897.
2. 'The Natural History of the Marketable Marine Fishes of the British Islands.' By J.T. Cunningham, Naturalist, Brit. Marine Biol. Assoc. 8vo. London, 1896.
3. The circumstance was known, however, to Spallanzani, Kusconi, and others, in Amphibia a century ago.
4. The German remarkable "Plankton" Atlantic Expeditions are object lessons.
5. Address at the opening of the new building (Marine Laboratory), generously presented to the University of St. Andrews by the Rev. C.H. Gatty, East Grinstead, Kent, 1896.