H.—ls

Of the stripped salmon marked with distinguishing tags during the hatchery season of 1925, two were recaptured during the 1926-27 season. The particulars are as follows : MD 17 : Liberated in Uptikororo River, June, 1925 ; recaptured in Lake Te Anau on 18th December, 1926. On liberation its weight was 5 lb. and its length 25 in. ; on recapture its weight was 6 lb. and its length 26 in. MD 387 : Liberated in Upukororo River, July, 1925 ; recaptured in Upukororo River, 28th February, 1927. On liberation its weight was 5 lb. and its length 24 in. ; on recapture its weight was 5J lb. and its length 26 in. One must not generalize too sweepingly from the indications given by only two fish ; but the results from these two cases indicate that very little growth is made by a Te Anau salmon after it has attained maturity. It would appear that the nourishment obtained has been largely utilized in the development of the reproductive organs for the subsequent spawning. It points to a deficiency of foodsupplies as compared with the food-supplies available to this species in its European habitat. It is most probable that these two fish had not left the fresh water. Now, the acclimatized quinnat salmon of Otago and Canterbury which do go to sea make very rapid growth, which demonstrates that suitable salmon-food exists in the sea off these coasts. The lesson of this is that if the establishment of the Atlantic salmon is to be permanently satisfactory they must be induced to migrate to sea and feed in salt water, which is in fact their ancestral habit. The Upukororo breed, generally speaking, has apparently been satisfied with the inland fresh-water " sea " of lake Te Anau. The transplantations of Atlantic-salmon fry to the Wanganui River, made each, year since 1923, will afford a test as to the possibility of producing a seafeeding stock of salmon, for there they will have no lake in which they may be tempted to linger. It is early yet to gather any evidence in the shape of adult salmon from this Wanganui River acclimatization experiment, though there should have been four-year-old fish running in the past season. There is yet another open question : Is the Atlantic salmon species as well adapted to escape the many dangers of the open sea as is the Pacific quinnat species ? It is well known that a large proportion of the quinnat salmon show scar-marks indicating attacks by predaceous marine fishes or porpoises, which were partially successful. But the quinnat salmon in New Zealand waters are probably at least twenty times as numerous as the Atlantic salmon, and thus sheer numbers at the outset would ensure a " run " of survivors. There is no need to pursue the discussion further, but one is forced to the conclusion that the problem of salmon acclimatization in New Zealand is by no means disposed of by the successful transport of ova and the satisfactory production of fry from hatchery operations. There are other factors which condition the growth, reproduction and survival of the salmon upon which light must be thrown if the work of acclimatization is to be carried beyond the stage of planting out the fry and then hopefully leaving the matter in the hands of nature and the fishermen. Culture implies intelligent control, and this involves the understanding of the conditions, which can only be attained by systematic investigation. 1 have, &c., The Secretary, Marine Department, Wellington. A. E. Hefford.

MARINE FISHERIES INVESTIGATION STATION. Sir, — Portobello, Dunedin, 26th May, 1927. 1 have the honour, on behalf of the Board in control of the above station, to forward the following report of its operations during the year ending 31st March, 1927. The station was originally founded to facilitate the introduction of foreign food fishes and crustaceans, as contemplated by successive Governments at the close of last and the early part of this century. This work was carried on until 1913, when the last shipment of European lobsters, crabs, and turbot was received from Britain. The intervention of the Great War suspended all such arrangements, and the resulting dislocation of shipping precluded any immediate return to previous conditions. Recently, however, the Board has communicated with Sir James Parr with the object of ascertaining whether it is possible to resume shipments of Crustacea, and it is hoped that the result of the inquiries will be favourable to the proposal. Oysters. As stated in last year's report, the services of Mr. M. Young, biologist, have been transferred to the Marine Department. That gentleman, while still controlling the biological and hydrographical work of the station, has devoted a large portion of his time throughout the past year to an investigation of the Foveaux Strait oyster-beds. This work, carried on in co-operation with and under the supervision of Mr. A. E. Heft'ord, is the subject of a special report to the Department. Towards the end of October a large quantity of oysters was brought to the station for observational work. Part of these were placed on a rack in one of the ponds, while the remainder were kept in one of the inside tanks. In spite of the very shallow water, the great growth of Algae in the pond—a matter very difficult to contend against—and the generally adverse conditions, the oysters have done well One spawned in a tank in January, and the spat attached themselves to the glass sides in large numbers. By the end of March these small oysters had attained a diameter of 2 mm. This observational work is fully dealt with in Mr. Young's separate report.

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