SALMON.

Wellington Independent, Volume XXV, Issue 3086, 17 December 1870, Page 4

SALMON.

At a recent meeting of the Tasmanian Boyal Society, Mr M. Allport read the following notes on the salmon trout (salmo truttn), at the Eiver Plenty :— Another and important addition has, since our last meeting, been made to the history of the salmon experiment. It will be remembered, that in the winter of 1869, those of the salmon trout (salmo irutta) which were detained in fresh water first spawned, and when the egga batched, it became a question of great interest whether the fry would, in due season, exhibit the migratory instincts of their species in the same manner as if the parent fish had spawned after a visit to sea ; and this question became of still greater interest from the doubts entertained by scientific men in England, as to whether the fish detained at the Plenty were really salmon trout at all, spme going so far as to assert that they could not be genuine because they had spawned, and that no migratory salmon ever would breed without the previous journey to sea. The Salmon Commissioners, some- time since, sent to England specimens of the young fish, hatched from the first eggs laid by the salmon trout, such young fish being then seven months old, at which time they exhibited, in a marked degree, all the characteristics of the par of migratory salmon, and espeoally the orangecolored fins, which are looked upon as peculiar to the par of the salmon trout. Had the experiment stopped at the time when those young fish were sent away, many people might have jumped to the conclusion that young fish were really, as Dr Gunther suggested, hybrids and not salmon trout; but, fortunately, we have now in the specimen on the table the most convincing proof that these fish belong to the same migratory species of salmon, and we have therefore, no right to doubt the statements of those who Bent the eggi from which the parent fish were produced, and must admit that their progeny are true salmon trout. The specimen before you (representation 5) is a facsimile of some 300 others now in one large pond at the Plenty, ail of which have assumed the full smolt dress of brilliant scales, which dress is not only the invariable characteristic of those species which migrate seawards, but . also the unerring sign that they are ready to depart. Besides the great fact of the final success of the salmon trout, which this specimen abundantly proves, there is another interesting point to which desire to call attention. Of the two smolts caught in the estuary of the Derwent in the end of October last year (that is the very same season at which this specimen has been taken from the pond), one was sent to England and pronounced, by Dr Gunther to be an abortive salmon trout ; the other was kept here, and is now before you. Upon comparing these specimens, you will find that the salmon trout smolt from the pond at the Plenty, though a healthy, wellfed well-shaped, silvery fish, is not one-fourth of the weight of its abortive brother, and they exhibit other differences which make it difficult to believe that they are identical in species. During the last fortnight the parent salmon trout, unhappily reduced in number to 11, and which first assumed the smolt livery three years ago, have exhibited marked restlessness at their forced detention, swimming round and round their pond seeking an outlet, and even throwing themselves out of the water at the lower grating in such a determined manner as to render it necessary to iv crease the height of the guard to prevent their escape.