Food from the sea. Remarkable results of the experiments in cod and lobster,(aquaculture, 1890)

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Food from the sea. Remarkable results of the experiments in cod and lobster,(aquaculture, 1890) - a if to ia in so a FOOD FROM THE SEA,...
a if to ia in so a FOOD FROM THE SEA, Remarkable Results of the Experiments Experiments in Cod and Lobster. REPAIRING RECKLESS RAVAGES. Seventeen Million Fish Grown Seven Hundred Captives. From THE L0BSTEE FIGURES EYES HIGHER In August last, writes the Eev. M. Harvey, Harvey, a scientist of exceptional attainments, now at St John's, Newfoundland, I gave an account in the New York Tribune of a visit I paid to the cod and lobster hatchery at Dildo Island, Trinity Bay. This is the largest establishment for the artificial propagation propagation of fish in the world. The operations operations of the hatching season are now drawing drawing to a close. , The artificial propagation of codfish and lobsters, as well as other salt water fishes, is a matter in which the civilized world is deeply interested. If it is possible by that process to increase, to any considerable extent, extent, the supply of food fishes drawn from the ocean, this achievement will be of great benefit to the world. Under the teachings of science, agriculture has made enormous strides, doubly or trebling the productions of the soil; but aqua-culture is yet in its infancy. infancy. The dav is not distant when it will be seen tha.t the cultivation of the waters is not less important than the cultivation of tbe lands as a means of increasing the supplies supplies of human food. EECKLESS OP THE ETJTTJBE. Keen-eyed science has of late turned her attention to an investigation of the nature and habits of those denizens of tbe waters which furnish food for man. Prom all quarters quarters comes the alarming cry that the supply of the most important of these fishes is falling falling off; that fisheries once abundant are exhausted: exhausted: that certain fishes are threatened with absolute extermination through human human cupidity, recklessness and ignorance. Can science remedy this, and sustain or increase increase our supply of food from river, lake and ocean? As tar as fresh waters are concerned, concerned, this question is already answered in the affirmative. But fresh water fishes are insignificant, in an economia point of view, when compared with those which the great ocean yields. Can science help us here? In the great experiment of the artificial propagation of marine fishes, the United States of America has the honor of leading the war. Associated with the enterprise are the names of Prof. Baird a naturalist of world-wide reputation Profs. Verrill and Brown Goode, Messrs. Miller and Sanderson Sanderson Smithman, eminent in the world of science. Great advances have been made, but far more remains to be accomplished. The success already achieved gives, however, however, glorious promise of what is to follow. SCIENCE AND FBACTICE COMBINED. Here in Newfoundland we are following the path which Prof. Baird's scientific investigations investigations opened up, and endeavoring to turn these to practical account. "We have been fortunate in securing the services of an able Superintendent of Fisheries in the per son oi Mr.Adolph Nielsen, who scent many i years in connection with tne .Norwegian fisheries as one of the inspectors, and who combines, in a remarkable degree, scientific knowledge with large practical experience. I am now to give some account of his hatching operations at Dildo during tbe past summer. Mr. Nielsen carried on simultaneously at Dildo the 'hatching of codfish and lobsters. The ova of the two species are totally different, and require very different methods of treatment. The cod ova float, being oi less specific gravity than the sea water; whereas tbe lobster ova sink to the bottom of the apparatus. Generally Generally "speaking, cod-hatching is a much more difficult operation than lobster-hatching. The eggs of the cod are extremely delicate, delicate, so that the slightest injury is enough to destroy their vitality. The utmost vigilance vigilance is needed in securing a constantly renewed renewed supply of pure salt water, of a certain degree of salinity and density, during the hatching time. LOBSTER OVA MORE HABDY. Then the eggs, after being taken from the female, have to be fertilized by contact with the milt; and no small difficulty is encountered encountered in securing a sufficient stock of male and female codfish at the proper spawning stage. On the other hand, nature presents the lobster ova already fertilized and clinging in thousands to tbe fibrils under the tails of the mother fish. They have only to be removed carefully and placed in the hatching jars or incubators, and they bear a rongher handling than the others. Mr. Nielsen succeeded in securing 700 spawning codfish in various stages of ripeness ripeness in May and Jnne. These were placed in pounds surrounded with wire netting, to which the sea water had free access, and fed on whatever bait-fishes were in season such as herrings, capliu and squids. As the ova and milt ripened tbe fish were "stripped" and then returned to the pound till further ripened; for a female cod takes from six weeks to two months in shedding her ova, and same holds good of the male fish. The ova, when fertilized, are placed in the hatching jars and carefully watched and constantly cleansed. Dead ova have to be at once removed. , OYER SEVENTEEN MILLION HATCHED. Night and day the steam engine is pumping pumping sea water from a depth of 30 feet. All this involves much labor and watchfulness. Up till July 28 he had collected 33,820,000 cod ova. Of these 16,720,000 were rejected, aad 17,100,000 were hatched, and the young fish were "planted" in a good and healthy condition in tbe waters ot Trinity Bay. Thus 50)4 Per cent of the total ova obtained were successfully hatched, which is a satis factory average. Ot tne 700 cod captured, 28 per cent died from various causes, such as injuries received received from the hooks when taken, or afterward afterward in handling, or diseases of different kinds. It is curious to find that many of the fish carried dead ova in very large quantities. quantities. This is supposed to be caused by the ravenous cod gorging themselves on the caplin to such an extent that the overloaded stomachs press unduly on the ovarite and injure the delicate ova. Mr. Nielsen would have obtained a much larger number of ova from the fish which were bandied but for the destruction arising from this cause. PEOSPECTS FOE THE FUTURE. There are, however, still in stock in the pounds 260 fine fish, or 37 per cent ot the whole, and from the condition in which these are now Mr. Nielsen expects that a number will spawn, in a fevr days, so that he will be able to go on hatching up till December December or later, and thus considerably increase increase the number already planted. He also hopes to preserve a number of these splendid cod that will not spawn this year, so as to give him a stock of ipawners in early spring next pear. "Whether they will live iu the pounds throughout our cold winter is doubtful, but the experiment is worth a trial. Another difficulty Mr. Nielsen had tr contend with this year arose from the enormous enormous quantities of ice around the coast, which chilled the waters and kept the cod irom coming in to spawn till late in the season. This curtailed the supplies of cod and caused many to spawn outside in deep water, where they could not be taken. The great object is to obtain plenty of spawning fish early in tbe season, so as to give time for hatching on a large scale. In his hatch-, ery Mr. Nielsen has capacity for hatching 300,000,000 of cod in one season. Owing to the difficulties and drawbacks referred to, his "output', or young fry this year will not probably exceed 25.000,000 or 30,000,000. Much depends on the condition of the weather between the present date and Christmas. Should the temperature fal below 38 degrees hatohing would baye to be discontinued. Next Tear Mr. Nielsen intends to fit op a small vessel with wells in which coi can be collected at various points around the coast as soon as they appear and brought early to the hatchery. He thinks, too, that by collecting collecting the finest fish around tbe shore he will be able to improve the breed by crossing the Trinity Bay fish with superior varieties, snch as those Irom Cape St Mary, which are of a large size. By selected stock the breed of cod can be improved, as well as on land the breeds of cattle are improved by a similar process of selection and crossing. The audacity of science in these days takes away one's breath. Twenty-five or thirty millions of young cod added to the stock in Trinity Bay means a great deal. Let this be continued for a few years and scarcitr of the noble cod will be transformed into abundance. That is not all. Tbe fishermen of Trinity Bay report from various places that they have observed immense shoals of very small codfish in the waters, such as they never saw before during the latter part ot September and October. Tbey were not when observed more than an inch or two inches in length. Mr. Neilsen has no doubt that these are the growth from the irv planted from his hatchery late in June and in July. In September and October October they would have just reached the size oi those seen. This news is of the highest importance importance and affords abundant encouragement NIELSON'S LOBSTER NESTS. Mr. Nielsen's success in lobster-hatching has been more striking than in the former department and, indeed, has exceeded the most sanguine expectations. At Dildo he obtained 20,927,200 lobster ova from various lactones within reach. Of these 13,07O,8UO were hatched and planted, against 4,039,000 planted last year. The percentageof loss in the apparatus this year was 28, against 49J last year showing a marked improvement in the method of manipulntion the result of experience. These 20,927,200 young lobsters lobsters were set free in the waters of the bay, where they would have the same chance of survival as those brought to life iu the natural way. This, however, is only a part of the tale. For the first time, this year, Mr. Nielsen has employed floating inenbators for tbe propagation of lobsters. These are small wooden boxes, so constructed that when anchored anchored in suitable localities tbey are constantly constantly in motion, and allow a flow of pure sea water, aerated by the motion ot tbe incubators, incubators, to reach the eggs. These incubators incubators are Mr. Nielsen's own invention, and show much ingenuity. Four hundred and thirty-two of them were made. Men were carefully instructed as to their use. They were then distributed at 14 different stations around six of our largest bays, from Fortune Bay to Green Bay, in tbe North. BESCUED FEOM THE FACTORIES. They were placed iu carefully chosen localities, where the water was pure and sufficient sufficient shelter could be found. These places were in the neighborhoodof lobster factories. The men in charge of the incubators visited the factories daily and carefully removed the ova fastened to the fibrils of the mother lobsters, and placed them in tbe inenbators, where in due time they were hatched, and when strong enongh to strike out for themselves themselves they were liberated in the waters. The method is simple and inexpensive Twenty-four men were sufficient to work 432 incubators. Their wages were SI a day, with traveling expenses paid. The cost of the incubators is 52 each. Any man having ordinary intelligence can be taught the method of working them in a short time. Now let us see the result of this season's operations. Betnrns have been received from the 14 stations and carefully tabulated. The returns show that 390,934,500 of lobsters were hatched and planted in the waters. Adding to these the number hatched at Dildo, by Mr. Nielsen, we have 406,005,300 young lobsters hatched and planted in one season. QBEAT SAVING OF LIFE. Let it be noted, too, that these ova were all doomed to destruction, and had they not been turned to account in the incubators would have been consigned to the boilers along with the lobsters. That they were saved and brought to life is a clear gain. Should 20 or 25 per cent survive and reach mutur-ity mutur-ity or even half that n'umbei what an addition addition to the stock of lobsters in the waters in which tbey were placedl It seems to me that in this cheap and simple process we have tbe means of arresting arresting tbe decline in lobster fisheries which for years past has been experienced in every country where they are taken, and also of restoring lobster-grounds which have been entirely depleted. Protective legislation and 'enactments to secure close seasons have all failed to arrest the rapid decline in lobster fisheries. Here is something more effectual than restrictive measures. Instead ot consigning these precious germs of life to the boilers, let each factory be furnished with a set of incubators by which the ova can be brought to life. The owners and managers of the various lobster factories here who witnessed the process with their own eyes are delighted with the discovery, and we anticipate that the day is at hand when they will all, for their own advantage, procure and work these incubators at their own expense. ONE LOBSTEE YIELDS 18,970. From the tabulated returns some interesting interesting facts are gleaned. The total number of lobsters stripped of their ova at the whole of the stations was 20,599. Tbe total number number of lobsters hatched and planted from the eggs thus obtained was 390,934,500; so that tbe average yield of each lobster was 18,970. The total number of ova collected from the 20,599 lobsters was 482,554,260; so that the loss per cent in hatching was only 19. The annual value of our lobster fishery is over S200.000. Bv due care and an exten sion of artificial propagation we may hope to increase its value ten-Told. In our proximity proximity to European markets we possess an important advantage. This year the price of lobsters has increased 25 per cent, owing to the scarcity of the "favorite crustacean. The lobster is five years in reaching maturity; maturity; so that the eflect of artificial propagation propagation will not be felt very sensibly for some time. Our fisheries commission will probably probably double or treble the number of floating floating incubators next year. TJHDEH THE MICBOSCOPE. Examples of the "Wonders "Which ThU In. strument Kovcals. "Within 30 years a fascinating branch of geological study has been developed. Bocks and minerals as seen under the microscope present a wonderful display of colors, and in structure a great variety of forms. Dr. H. Hensoldt, says the Youth's Companion, writes of the pleasure and interesting interesting information afforded by such observations. observations. Especially striking and lovely is the appearance appearance of many of the volcanic or igneous rocks, when rednced to tbin sections, and examined under the microscope. The dullish dullish green lava, called pitch stone, which is found in dikes on tbe island of Arran, on tbe west coast of Scotland, exhibits under the microscope whole forests of fern trees, garlands, leaves and flowers of marvelous magnificence. A granite from Cornwall contains needle-shaped crystals of tourmaline, tourmaline, radiating star-like from a common center. center. Basalts, obsidians, porphyries and serpentines serpentines from various localities show labyrinths labyrinths of multi-colored crystals resembling rows of pillars, t arreted castles and fairy caves, glowing in all the tints of the rainbow. rainbow. Tbe sedimentary or stratified rocks, while they cannot under tbe microscope, equal their Plutonic rivals in brilliancy of color or gorgeousness of crystalline display, make up tor this deficiency by other ieatures of interest Many marbles and limestones are found to be literally composed of foraminifpra. the tests ot rbizopods, resembling tiny shells of the most delicate and beautiful forms. Thin sections of almost any piece of flint exhibit under the.microscope quite a little world of curious organic remains, such as sponge spicules, xantbida, small fragments of coral, and the formaminifera already mentioned, indicating that flint rocks are fossil sponges which have become solid by a modification of the process which makes j stalactites, a 1

Clipped from Pittsburgh Dispatch23 Nov 1890, SunPage 23

Pittsburgh Dispatch (Pittsburgh, Pennsylvania)23 Nov 1890, SunPage 23
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  • Food from the sea. Remarkable results of the experiments in cod and lobster,(aquaculture, 1890)

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