THE FISH HATCHERY. FISH AT COOPER ISLAND. NOTES BY THE WAYSIDE.

Otago Witness, Issue 2358, 4 May 1899, Page 62

THE FISH HATCHERY.

FISH AT COOPER ISLAND.

NOTES BY THE WAYSIDE.

By R. Henry.

Above all creatures, it seems necessary for sea fish to go and come — after their food, perhaps, in the first plase, and then for breeding, as in the ca^e of the salmon. If it was not for the salmon's necessity to spawn in rivers we woxild know as little about them as we dc about the ribbon-fish, for we almost know nothing about them after they go to sea more than that they grow bigger, — we do not know what food they grow \ipon nor where they get it. We are in about the same position with regard to hen ings, though they have been studied since England first had a name. The first fisherman who caught one or took it from a gull and appreciated it would begin to study it, and would probably note that it had ripe eggs and would have spawned not far off ; and that is about the position of our information at the present day, notwithstanding our hatcheries and biological stations. We know that the cod and other good food fishes eat herrings, and perhaps the salmon does the same. Therefore the first thing we want to know is what the herrings eat, and whether the food exists here or not before we bring their eggs. Thr.* we are not likely to find out directly, but we might draw something by inference from the habits of our native herrings, the pilchards and sprats that visit us sometimes, but stay away so long that fish depending on them would probably starve if they did not follow them into the mysterious places of the sea, where there may be other food to share with them. Then I cannot see how we are going to find out anything about those mysteries by keeping fish in a hatchery on artificial food. It would be like studying cuckoos in cages. But if we could bring out some big, full-grown fish and let them go in a shoal of sprats or pilchards they might live until they learned where to lay the ; r eggs so that the young might survive. If we attempt that task we are almost sure to make a mess of it, because we do not know enough about the conditions under which the young require to get food and escape their enemies. Perhaps the cod's eggs would be laid in time and place so that the young coultl live on waste pilchard eggs, then on young pilchards or others, and so on till they grew right up. And when we know the oj>posite ideas of the eel and the salmon we can guess at our ignorance about others that can keep all their social affairs to themselves. If we turn out a crowd of small fry in a strange place where there may be no suitable food but a horde o^ wrasse and rockfish for enemies, it is a forlorn hope for one of them to survive. I have heard that fishermen at Home keep their live cod and other fish in " wellboats " for a considerable time, and that these fish will feed there and can be fished out with hook and line. Therefore, I would respectfully suggest that the hatchery and biological station be established on board one of the big swift steamers, and that not a penny be spent to feed the fish that are now loafing around Purakanui. With the great empty meat chambers that will soon be available and machinery constantly going, the temperature and aeration of a series of tanks might be controlled by a qualified biologist and mechanic, at least through the Red Sea, and after that free communication could be established with the ocean when the temperature was suitable. Some of those tanks might contain little fish to feed the big ones, or they might be mixed together as they are in the sea. The tanks could be made with a side of class so that their proceedings could be watched and something learned every trip until success was attained. The first cost would be great but the other colonies might get out some fish and share in the expense if the. idea is practicable, and I cannot see why it should not be. Perhaps the ballast tanks in some of the great steamers now building could be modified for ventilation and insulated, lined with guttapercha, floored with stones and growing seaweed and its usual populations, lighted with electricity and portholes, all specially for carrying live fish. I would not be surprised, if in years to come, the practice would be a-s common as carrying ducks and fowls, as the principal appliances are all at hand, and idle, we may say, when coming out. Then when the steamer would be coining near, information might be gathered as to where the shoals of pilchards and sprats weremp about Moeraki, and she could just go up there with her fish and flush them into the sea. If the Red Sea was too salt or too hot she could come by the Cape.

By R. Hexry.

On February 17 Sportsman's Cove seemed to be alive with fi&h. I had been in there several times previously, and thought it a poor place for fish, but this time the spell of fine southerly weather had made the water clear and there was a great swarm of the transparent mysis there. The weather had brought the little fish and they brought the big ones. First were garfish of large sizes, then barracouta, grope", kingfish, mullet, and some others xike mackerel. There were also plenty of big moki and the usual droves of parrot fish and their many cousins, all having a great feed of mysis, or ieeding someone else. Ihere was a regular partfc, and there were sharks, too, of course, for they came up for my fteh heads in the evening, and amused me gyrating about in the shallowwater. They would, however, stay near the bottom during the day, waiting for any refuse that would come down, or wounded fish, which they would save from lingering deaths. They would also attend to any of those that had over-eaten themselves, ior this often happens in a dense shoal of mysis. Sometimes I pick up one of those sick parrot fish with the spear and find

that it is just bloated with a great handful of inysis," and -when a shark gets one of those, you see, he gets mysis along with his fish. He is too big to catch it himself, so he rr^s the parrob fish to catch it for him ; and it is no fool of a job, because I have seen a parrot fish try one several times and then fail to get it. Though the mysis cannot travel very fast, it can skip aside like a shrimp, so that the more a fish rushes at it the more he seems to miss ; and I like to see the parrot fish miss, for they are cheeky, useless things, with teeth like cats, that can take off a bait in two winks without ever getting caught on a big hook. Ido not know where this mysis comes from, nor what it eats, but I know where it goes to. It goes down some fish's throat for certain, but this must be after ample provision is made for renewal, because they always appear again when the weather and water are suitable, even in June. If they were ready for eating in a given place on a given date it would be easy to understand, because the kakas know when to come for the honey and the pigeons for the berries, but you never know when or where the mysis will be ready, though, the fish seem to know exactly. I have not seen either barracoula or kingfish here for three years, and never saw a shoal of garfish here before, so that a fisherman would need to know a great deal more about them than I do to be always successful

Next day they had nearly all left the cove, and though I have been about the sound since, I have not seen such another party as that, I have, however, seen barracouta and mullet in several places. I wonder how all those lish knew that the mysis would be ready for eating on the 17th of . February in Sportsman's Cove? Some will say that they followed them in there, but I hardly think so, for they could not last moving about. I think that they were reared in there, and perhaps had an appointment with Lhe fish, or made some other arrangement with the fHi equally mysterious. However, they all seemed to have had great sport while it lasted ; ar.d all in order, too, for it was the same old game of life that has been played over and over again since the world began. If we could get a big shoal of mysis to go into Waikouaiti Buy there would soon be plenty of fi«h without hatching them. Thus it seoms that it is a mysis hatchery £hat we want ; or, belief still, a hatchery for mysis' food, whatever that mieht be,, but I suspect that a great part of it consists of fishes' floating eggs, so that it would be the usual tangled problem when we entered that domain.

-M. Thomsox, F.L.S.)

(By GKe.-

As the days shorten and the sun gets lower in the north, the groxind begins to assume its winter dampness, and the falling leaves and decaying vegetation give a deadened aspect to all nature. This is particularly noticeable in the neighbourhood of Dunedin, where the prevalence of hills ani vales, with their still remaining^ stretches of woodland, forms so many shady spots which the sun seldom touches in the winter months. Our hills, 100, so high and so near the sea, cause a much greater condensation of moisture than is common either nortl^ or south, so that though the rainfall may not be excessive, there is a great prevalence of mist, especially when th-i wind is from the north-east. Though the actual amount of rain which falls in Dunedin is smaller than that recorded from many other centres — for example, from Auckland or Wellington, — yet the atmosphere here is so often at saturation point that dampness may be termed one of its chief characteristics.

In -writing recently of the modes of distribution of fruits and seeds, a subject which naturally suggests itself at this season of the /ear, I made mention of the Piri-piri (Acasna) as a curious example of a plant dependent on passing animals for the scattering of the fruit. I pointed out the fact that while the species with a wide distribution outside of New Zealand had barbed fruits, the indigenous forms had lost these devices. A' parallel case is fuinished by certain sedges belonging to the genus Uncinia. These grass-like plants (with cutting edges to their leaves) are found along the fringe and in the more open parts of the bush, as well as in damp sedgy ground. They are, for instance, abundant about the shooting range at- Pelichet Bay. When the fruiting spikes are ripe, they are furnished with long bristles carrying a strong barb at the pomt — one to each fruit, — and these catch on to any passing animal. The explanation of this baibed structure in a New Zealand plant where there are no indigenous mammalia, is the same as that for Piri-piri. Uncinia is a genus which ranges to South America on the one hand, and away to Australia and Africa on the other. This wide range points to a considerable antiquity for the genus, and its "mode of distribution has evidently been developed in lands where mammals were to be found. Of course both Piri-piri and Uncinia might be distributed by ground-birds, but the fact already stated as to the tendency . in the former plants to disappearance in the barbs shows that the method 'is not very effective. Another very common and effective mode of seed-distribution has been much in evidence during windy weather recently. Many plants develop their fruits or seeds (the terms in many cases are used indiscriminately) in such a way as to be caught and scattered by the wind. Willows, some poplars, willow-herbs (Epilobium), and that common white-flowered bush climber Parsonsia have small seeds furnished with tufts of hair, so that when the seed vessels open and set their contents free the little seeds float away on - the slightest breeze, each borne on its own little parachute. In the 'clematis each fruit has a long feathery style acting in the same way. An almost identical device occurs in the fruit of the great order of Composites, an order containing some 12,000 species, in a vast number of which (exemplified by thistles, dandelion, groundsel, etc.) the tube of the calyx develops into a crown of hairs or~ bristle? — the socalled pappus, — by means of wk'ch. the

fiuit is carried on the wind. It is in greaij part owing -to this exceptionally good mode of scattering their seeds that Composites are. not only the most numerously represented, but also the most widely distributed of all orders of "flowering plants. Their nearest allies, , the Scabious, or pin* cushion flowers, and the Valerians Kre much more limited in their range.

Into the gutters and .sides of footpaths, where dust loves to congregate, the wind has during these last few M'eeks swept many of the winged fruits of the maples and 'ash trees. The latter tree has a single nut, bearing a long flat expansion of its outer covering, which acts like the sail of a windmill, while maples have usually twin nuts with spreading sails. On a breezy day they go whirling along in the air till they come to rest in some damp or sheltered spot, where they promptly commence tj grow. Natives as they are of Northern Europe, where the winters are very cold, there is nothing in our mild winter season to stop their immediate development. Pick up a maple fruit, and take off the outeF. covering so as to expose the seed, and you will be surprised to find how far advanced the future plant is. Its first pair of leaves are lying there, all green (though-hidden from the light) and ready for action, while its root is well developed. «• . '•'■'• The different extent tQ : , which the rudimentary plants found inside: of ' seeds' are developed is as interesting and v as diverse as the varying degrees of development shown in young birds when hatched out of the egg. It is well-known that chickens ciii run about and peck as soon as they come out of the shell, and some gallinaceous birds, such as grouse and partridges, are even still more advanced. Those who have had some acquaintance with country life in the old land know that if a grouse is flushed when, her covey is hatching, the old bird will fly off with a loud alarm cry, at sound of which the clucks run off to cover in all directions, some of them, perhaps, carrying part of their shells on their backs, because they have not had time to get rid of their former domicile. >

On the other 'hand what a helpless little creature a newly-hatched sparrow or a pigeon squab is, and how utterly dependent ie is for weeks on the care of the parent biids, as it slowly develops its limbs and feathers while still in the nest.

Somewhat similar is it with seeds. ' Some are ready to spring into active life-work at once, others take weeks, months, or even years to develop their embryos into plants able to feed themselves. The seed of a cress plant, for instance, has its first root and pair of young seed leaves well deyoloped as soon as it is ripe, and if sown in damp warm weather both of these organs are able to assume their functions and ,to support the new plant in the course of a few days. But if you split open a cocoanut you will find the other type. At one end of the nut — near the three finger marks — is a small rudimentary plant whicb will take months to force its way out of its shell, and which will reqiiire to absorb nearly all the food material stored up inside the nut, before its toot and stem are sufficiently developed to perform their full functions.

Just as there are among birds Avhole families in which the young are well advanced when hatched out of the egg, and others in which they are in a very inperfectly formed condition, so there are families of plants with very fully developed embryos in their seeds, <md others in which the embryo is in a very rudimentary condition and has a store of nutritive material laid up alongside of or round it, and which it must use up before it is ready to begin life on its own account.

In both cases the development of the young has no direct relation to the ultimate development of the adult form. Thus some of the most highly differentiated birds hatch out their young in a Very imperfect condition, whilst those which are so very wide-awake as chickens are not characterised by great intelligence in the adult state. The seeds of plants belonging to the Cruciferae always have -the embryo in a well-advanced condition, while ,the highly de\ eloped family of "orchids — most wonderful and, in some respects, most highly specialised of flowering plants, have their embryos in the most elementary- condition known.

Insects are becoming rarer as winter approaches, but it is singular how many revive and come out on a fine warm day. Only yesterday numbers of flies of two or three species were to be seen on the flowers of the common purple hybrid veronica. No doubt they mostly die off at this season of the year, but many merely become torpid for a time, and are tempted out again by a warm breeze. Mr A. Bathgatc has informed me of the occurrence of a very rare and interesting visitant in his garden, which made its appearance there within the last fortnight. It v/as a- solitary specimen of Vanessa (Pyrameis) itea, a beautiful butterfly allied to our common Red Admiral. It is a smaller insect than Vanessa gonerilla with yellowish instead of red spots on the forewings, and with a faint row of dark spots instead of the vivid crimson patch on the hind wings. Mr Bathgate states that the one .seen was a perfect insect, apparently just out of the chrysalis, " not a storm driven waif," and mentions further that he has only seen it once or twice before in 35 years. I think that cne of my sons and I saw one in our garden a good many weeks ago, but the fact was not recorded at the time, as we were not able to get near enough to identify the species. Hudson says that it occurs in the northern portions of the North Island, and that he has only taken three specimens. It is a pity that more of the young people do not take -to collecting and also to rearing insects. It is surprising how little we know of the occurrence of the local species, and how much would come to be known if a few enthusiastic collectors could be found in various parts of the colony. It might then be found that the species referred to was not absolutely so rare, hufc that it was very erratic in its distribution. April 26, 1899.

One hundred and fifty per cent, is the dividend for the past year on the_ working of the, Hal Kyn Mining Company, in Flintshire