ATLANTIC SALMON

Southland Times, Issue 20110, 22 February 1927, Page 8

ATLANTIC SALMON

A LOCAL SUCCESS

TAGGED SPECIMEN RECAPTURED

STATEMENT BY MARINE DEPARTMENT

The announcement of the capture, by Mr C. F. A. Jones, of Invercargill, of a “tagged” Atlantic salmon bearing the label M.D. 17, will arouse intense interest among the members of the angling fraternity throughout New 7 Zealand. Very few anglers are unfamiliar with the efforts made by the Marine Department, to establish this splendid sporting fish in New Zealand waters and for this reason alone the news of Mr Jones s capture will cause much gratification, for ii shows that the work of the department has not been altogether in vain. Although attempts have been made to acclimatise Atlantic salmon in New Zealand waters it was not until a few years ago that any appreciable numbers of fish of this species were landed by New Zealand anglers and definitely identified by competent authorities as Salmo Salar, says the Wellington Post. These were caught by trolling in Lake Te Afiau, near the outlet of the Waiau river, in 1921.

Since that season, increasing numbers have been taken in this locality, which still remains the place par excellence for the capture of Atlantic salmon in New Zealand waters, though subsequently many good fish have been taken, both on the artificial and natural minnow, and on the fly, in the river Upokororo, which flows into Lake Te Anau, and in the lower reaches of the river Waiau.

These salmon were the outcome of the substantial efforts made by the Marine Department to acclimatise this “King of the Salmonidae” by the importation of two and a quarter million eggs between the years 1908 and 1911; to be precise, 250,000 were shipped from eastern Canada in 1908, one million from Britain in 1909, and the same number in 1911.

The Department established a hatchery at Lake Te Anau in which the ova were hatched out, and the fry were, for the most part, liberated in the river Upokororo. Each winter of the years following the first return of adult salmon in adequate numbers, this river has been the scene of hatchery operations, the ascending fish being trapped, artificially stripped, and the fertilised ova hatched out, the resultant fry being returned to the river Upokororo. After relieving the parent fish of their eggs or milt, several of them have been “marked” by the attachment of an oxidised silver tag in order that their growth and migration might be ascertained. Each tag is stamped with a distinctive number, which is recorded together with particulars of the length, weight, etc., at the time of liberation.

Angling at the mouth of the Waiau from Lake Te Anau, Mr Jones, who is a member of the Southland Acclimatisation Society Council, captured a salmon bearing the label M.D. 17. The fish was liberated in the Upokororo in June, 1925, when its length was 25 inches, and its weight 51b. In his report Mr Jones stated—“ Unfortunately it was getting dark when the fish was landed, and it was not until after the fish was cleaned that the tag was noticed. Girth above dorsal fin was 13in, length 26in, and weight (allowing jib for refuse and gills), 61b.” The tag, together with a sample of scales of the fish, was forwarded to the Marine Department. Commenting on this case, rhe Marine Department’s expert said that it was the only one out of a total of 448 stripped fish which were tagged by the Department’s hatchery staff at Te Anau in the winter of 1925, the recapture of which has been reported. It is usual for the majority of spent salmon to perish, which would principally account for this small proportion of returns. Doubtless also, the inconspicuousness of the label may have caused it to be overlooked in some cases. It may be explained that oxidised silver is used for the mark in preference to the bright metal because it has been found by experience that a glittering decoration renders a fish too conspicuous and an easy mark for attack by predacious enemies.

The remarkable fact about this case is the very slight increase of growth which is shown for the intervening period of eighteen months between liberation and recapture, as compared with the growth of European salmon for a similar period. It seems probable that this fish remained in fresh water for the whole period, and that its food supply was mainly utilised for the maturation of the reproductive organs for the second spawning, which, had it remained at liberty, would have occurred in the winter of 1927. It is interesting to notice that in this case at least a period of two whole years would elapse between the first and second spawning of the fish.