ACCLIMATIZATION

Southland Times, Issue 21196, 24 September 1930, Page 6

ACCLIMATIZATION

THE WAIAU SYSTEM < DETERIORATION IN FISH . CONDITION HOW TO OVERCOME IT 6 6 (From Our Parliamentary Reporter.) Wellington, September 23. Referring to the arrangement whereby 50 per cent, of the Atlantic salmon ova taken at Te Anau should be returned to the Waiau system, Chief Inspector of Fisheries (Mr A. E. Hefford) in his report embodied in the Marine Department’s report which was presented to the House of Representatives to-day, states that he is of the opinion that the principle is one that should be followed in most cases and especially where there is evidence of comparatively little natural reproduction in streams from which fish-are taken. After referring to the number of fish taken during the past’ season and to the contention that the fish in the Waiau' system are deteriorating in condition, the inspector states: “Attention may be drawn to one unquestionable fact and that is that a considerable proportion of the fish taken in the early part of the fishing season are kelts (spent fish) and inferior, both for sport and for eating. It has been suggested that no fishing in the lake should be allowed in October and that the river Upukuroro and an area off its mouth should be closed for a longer period. This, I think, is a desirable measure which should be brought about before the next fishing season opens. The river and its threshold should also be a sanctuary during the later portion of the fishing season so that ripe or nearly ripe fish may be saved for reproduction since ripe fish are to be found throughout the period from April to the end of-August. The problem of protecting gravid or spent individuals is admittedly difficult It is probable that early spawning individuals are of most value and should be preserved for propagation as far as possible. This question, however, which calls for special investigation and information about occurrence and habits of species, is still too limited to enable us to form any comprehensive ideas as to the present conditions, either from a biological or fishing standpoint. The collection of scales and other biological material is being continued and such observations are made as there are opportunities to make. In this connection we must acknowledge our indebtedness to the Southland Acclimatization Society's officers for their-co-operation.” Another section of the report states that in future with the co-operation of the Southland Acclimatization Society it is intended to -extend stock more generally throughout the Waiau watershed and not leave the Upukuroro alone to provide for propagation and nurture of young fry. It SQerns doubtful whether this can be done expeditiously with ova obtainable for cultural operations from existing stock, especially if any further consignments are to be sent north and in view of the importance of demonstrating conclusively whether acclimatization in the Wanganui River is possible or not, planting operations in that system should be continued over a ten year period (to 1932), provided that 50 per cent, of the Te Anau hatchery output will afford a quota of sufficient numbers to warrant transportation.

The inspector recommends that at the earliest opportunity a further importation of Atlantic salmon ova from Britain should be made arid, that the resultant fry should be introduced into the Waiau system for recruitment of that stock which could then be used for the stocking of further rivers. Those for which successful acclimatization of salmo salar appears most probable are rivers flowing into the sea on the south and east coasts of the South Island.