FISH CULTURE.

Otago Daily Times, Issue 6093, 20 August 1881, Page 3

FISH CULTURE.

TO TOE EDITOR.

Sir,—Your Lake County correspondent, under the above title, has given publicity to his ideas on the (uture fisheries of our great inland fresh-water lakes, based upon the apparent success of the trout (S. jario)exporiment in these waters of.Otago, and there is very much ho says in which I heartly concur; but 1 tin har.ily prepared to admit that the tirao has arrived when extensive fisheries should bo started for the I sale, locally or abroad, of the trout now growing in I I,ake Wakatipu and other lakM, though I may admit it is time that Government had looked on local clrorts in fish rearing with a more kindly ink-rest. There appear to be C6rtain facts about Lake Wakatipu and the trout in it which should, on cousideration, restrain our onthußiajm and make 119 ank, Isj the trout really the ilah which will ultimately be a i success there? Lake Wnkatipa is essentially diitorent I from tho lakes of Great Britain, where trout arc native and abundant. Its waters are snow-fed and of a great dept); (1300 ft), and Its fallows are ncithor numerous nor very promising. These conditions are not the best that could be desired, and therein it differs (or tho worse from most Homo lakes, the habitat of trout. Wo know also that the trout aeplimatiscd In Otngo rivers already show differences in habit, during the breeding season and at other time.i, which could scarcely have been anticipated; and in summer, autumn and wintor tho Wakatipu trout have been aeon in shoals of fifty, a hundred, or more, swimming n round the shoreß at such places an tho Onomile Creek, the Quoenstown Jetty, and Queenstow;. Bay, but not as yot in the Frnnkton arm so fjras 1 have heard. Just a month ago two gentlemen, while walk- j ing along the recreation-ground or peninsula, at Queenstowu, observed what they described as " acres of water" covered with great trout, which were swimming quietly about oa if on the feed, and themi-fllves on the surface. IJow the most of f these great trout should have been pushing up the : Rees, Dan, Yon, or other rivers at this time of Hie , year, or actually on tho Bpawnjug-tyedg in these rivers. Thru trout :it Home, whan from one to three inched long, may frequen ly be seoa keeping together in Bhoala In tho riven, but such a thing thure as shoals of large trout is unknown. Again, how comes it that these great trout in Queenatown Bay refuso ta bo caught by ordinary flioa, baits, or other lures? Vorily, wo knowas yet very little, and have nearly everything to learn £ regarding the habits and ultimate success of trout in our alpino lakei. Meantime I would venture an 01----planation as to tho shoals of great trout in and about Quccnstown Bay, and thoir normal habits so far as obserred. I think they have all bora bred in the • small " town creek," but oil attaining & certain size I 1 in tho lake, they have become too largo to 'ascend E thoir parent stream any more, and they therefore 0. have gathered together, and keop searching up and t< down the lake shore within certain limits, looking for a rivor of sizo sufficient (or them to ascend. They do not find such a river, because they have not travelled far enough ; honce they huvo increased, and will coutinuo to increase in numbers, within the limited area ■ whore they have been seen. This in not a hopeful sign, and shows that something is " out of joint."

Then disease ha< appeared among the trout of Lake Wakatipu, and these flsh have been there but a few years at most. Mr Worthington has informed me that the disease is fungus. Now fungus, for seveial yearß past, has developed into an epidemic among the salmon in some of our finest salmon rivers in England and Scotland. So sorious I rid the evil become, that Government appointed a commission to investigate the matter, the result being a voluminous report and masa of cvidenco. The evidence is very conflicting, but overstocking and pollution arc frequently blamed as cau-ing the disease. Still, it may bo gathered generally from this evidence that there is something presently in or about the water of the rivers which is particularly conducive to the development of fungus. Whatever it be in the Wakatipu which cngondcrs tho fungus, it cannot as yet aiisc from over stocking, as it would take many years probably to fully stock a sheet of ordinary lake-water 50 miles long and one to three miles broad. It does seem to me rather that something eithor in tho chemical constitution of the water itsolf of Lake Wakatipu, or in Uir altered hahits of the trout (perhaps both), has caused thus early the appearance of so very undesirablo a malady. More facts and more details might be given by me, did the occasion warrant it. But enough perhaps has been stated abovo for tho information of anyone interested in the natural history or the ocononiic aiicces* of our trout, to show that It would be rash at present to establish net-fisheries for the wholesale taking of our lake trout.—l iun, &c, ' V/. Arthur. Dunedin, August 101b,