H.—ls

Dredge Oysters : Foveaux Strait, 1944 The 1944 season was less successful than that of the previous year, the same number of vessels producing 63,949 sacks, as against 73,119 in 1943, a difference of 9,170 sacks. To a great extent this can be attributed to bad weather, particularly in the month of June, when it was possible for the vessels to dredge only on five days instead of the usual sixteen to twenty days. The catch for June was thus 2,013 sacks in place of the usual 7,000 to 9,000 sacks for a normal month. Some of the decreased catches may also have been due to the fact that for a considerable part of the season the fleet was operating on the more distant grounds, which allowed less time for dredging. Four vessels exceeded the 7,000-sack limit fixed by the terms of the Bureau of Industry's license, but were allowed to continue dredging for the balance of the season west of the Barracouta Head - Gull Kock Line. In accordance with the policy recommended in the report on the 1943 season, it had been decided to adhere to the limit and to stop each vessel operating when the 7,000-sack total was reached. Representations were made, however, by the representatives of the oyster men and oyster merchants, and after some discussion it was agreed to allow the usual easement on condition that the parties concerned co-operated with the Department in carrying out a partial survey of those portions of the Straits outside the usual oyster areas during the 1945 season. This survey was commenced in February, 1945, and a report on the results will be given in the next annual report. Toheroas Good stocks of toheroas have been maintained on the North Kaipara, Muriwai, and Waitarere Beaches. The occurrence of beds consisting of exceptionally large-sized individual molluscs has been noteworthy, more especially on the North Kaipara Beach. The toheroa population on the Ninety-mile Beach, on the other hand, is in a condition that is deplored by those locally interested, and a matter of some anxiety to the Department. The beds are fewer and more sparsely populated and toheroas of takeable size are fewer than at any time since they came under the administration of this Department. As to the reasons for the deterioration, various causes have been ascribed. The ascertainable facts that appear to be most relevant are as follows (they are not given in order of importance, because it must be admitted that departmental observations and supervision in this remote area have never been adequate to provide the first-hand knowledge of the condition of the resources and the manner and degree of their exploitation that is necessary for proper and prompt measures of control; the wartime period has inevitably added to this handicap) : one new factor in the situation has been the stationing of comparatively large bodies of Army and Air Force units in the neighbourhood of the Ninety-mile Beach following the outbreak of war with Japan. According to some reports, the toheroas provided a very much appreciated addition to their daily rations and suffered considerably from their depredations. This was in addition to the not inconsiderable toil taken by local residents and by the cannery diggers. Although the abstractions made by these last two agencies may have been no greater than had been customary in the past, it constituted a larger proportion of the available stock, because the toheroa population had not very appreciably recovered from the 1938 mortality, when millions of the molluscs died in a few days from natural causes. Moreover, the existing beds contained a relatively small proportion of full-grown toheroas, with the result that, in order to obtain the same bulk of toheroa-meat, either for private consumption or for canning, a much larger number of individuals was destroyed. The regulation size limit, above which no toheroa may be legally taken, is 3 in., and there can be no doubt but that the general observance of this regulation would prevent any serious depletion of the beds. However, in the absence of any law-enforcing agency on the spot, or even of frequent patrols of the beach by a Fisheries Officer, this regulation was undoubtedly disregarded to an appreciable though unknown extent. There is further good reason for the view that, apart from the depleting effects of human predators, the toheroas in this area have been subjected to adverse natural conditions which have induced their disappearance or at least checked their growth and reproduction in recent years. The most obvious of these natural factors has been the invasion of the toheroa territory by vast numbers of the bivalve locally known as the tuatua (the common pipi of the Wellington district), which was mentioned in last year's report. The species is closely related to the toheroa, but has a thicker shell and does not grow to such a great size. As they get older these tuatuas tend to move out to below the low-water line, but up to a length of about 2 in. they live in about the same position on the beach as the toheroa, and their competition for space and food must be of serious effect upon the toheroas in the same habitat. In order to conserve the existing stock of toheroas on this beach, so far as human abstractions are concerned, a year's close season, ending 31st March, 1946, has been prescribed by regulation. Fortunately, the question of depriving the local people of their sea-food, particularly desirable as an alternative to meat rations under present conditions, does not arise, because in the place of the toheroa there are vast quantities of its near relative, the tualua, that will provide them with as much bulk of equally nourishing and, according to many, equally palatable protein food. Other Shell-fish Mussels Although edible mussels occur on many parts of the coast in both Islands, it is only in the Auckland district that a commercial industry of appreciable importance has been developed. The ports concerned are Auckland, Thames, and, to a less extent, Coromandel, where, however, a mussel cannery operates for part of the year-. The mussel-beds of greatest extent and of most importance, in that they produce shell-fish of large size and of best quality, are in the vicinity of Coromandel Harbour. These beds have been intensively exploited by dredging operations in recent years, with the result that they have become relatively depleted, and it has been decided to close the area to dredging for a period of three years. A regulation to this effect came into force on 3rd May, 1945. There are various other musselgrounds in the Hauraki Gulf and Thames Firth, but, generally speaking, they do not produce such large and well-conditioned mussels as those abreast of Coromandel. One dredging vessel works out

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