H.—ls.

considerable extent left in the world. In the case of practically all the oysters marketed at the present time in other parts of the world their production has been more or less assisted by artificial cultivation in some form or other. Farmed oysters naturally cost more to produce than those which are harvested from the natural beds. It therefore behoves us to see that our natural beds are duly conserved ; and to ensure this it is necessary that investigations to give us a better understanding of their true extent and their potential productivity should be provided for as early as possible. Toheroas. Only the more northerly of the two canneries was in operation in 1938, during which season 69,560 lb. of toheroa products were packed—approximately equivalent to 73,920 lb. of shelled toheroa —valued at £3,696. The quantity exported during the year was 42,302 lb., valued at £3,112. In reporting upon any class of our fishery assets the principal object should be to show how it stands up to date. It is a sort of stocktaking. This object is more easily stated than achieved. A complete understanding of the factors that make, on the one hand, for additions to the stock, and those on the other hand that make for subtractions from it, involves investigations that are both complicated and extensive. Without adequate and continued investigation the conditions can only be demonstrated imperfectly and to a limited extent. There is, also, inevitably a time-lag between the operation of the causative factors and the perception of their effects. For instance, a season may be much better or much worse than average for the natural propagation and survival of a species. The results, in a recognizably improved or deficient stock, do not show themselves, however, until some years later. In sea-fishes this will not be until the individuals from that particular supernormal or subnormal propagation have reached takable or marketable size unless, as is now the case in countries with highly organized fishery-research facilities, special investigations are made. Similarly, the depleting effects of over-fishing do not show themselves immediately, but are only apparent after a considerable lapse of time. In the case of our toheroa resources the stocktaking task is simplified by the fact that the stocks do not wander about in obscurity in the ocean, like sea-fishes or crayfish do, but remain more or less in the same place, where their comparative abundance can usually be seen with the eye and confirmed by digging in the sand to a depth of six or eight inches. For this reason the conservation of toheroa stocks could, and should, be one of our easier problems. In practice, however, it is not so easy for a limited staff of competent observers to cover with satisfactory frequency the many miles of beaches that form the habitat of this species. For every visit made by a departmental official for inspection or for ranging there are hundreds made by motorists who go to the beaches to supply themselves with these shellfish. It is a delusion to suppose that, because they are private persons digging " only for a feed," their effects on the toheroa population are negligible. The obvious depletion of stocks in various areas as the result of their abstractions has been recognized for some time, and regulations restricting the taking of toheroa to a daily limit of fifty per person, prohibiting the taking of undersized toheroa, and forbidding the use of destructive implements for digging have been in force, at least on paper, since 1931. It cannot be said that the universal, or even the general, enforcement of these regulations has been achieved, for reasons that will be understood from consideration of the conditions described above. The present abundance of toheroas on most of the beaches compares badly with that of former years. A considerable factor in bringing this about was undoubtedly the great mortality that took place in February and March, 1938, as mentioned in last year's report; but, in addition, the rate of abstraction by digging has also increased, and is likely to go on increasing unless something is done about it. It has therefore been necessary to submit measures for further restrictions on the taking of toheroas. The further decline in our toheroa stocks can be arrested only by the general application and observation of conservational regulations. Much depends on the disposition of those who frequent the beaches to put the community interest in natural resources and our obligations to posterity above petty individual selfishness, a disposition which, in the absence of strict supervision and drastic penal measures, has in the past been too frequently found wanting. If satisfactory conservation by the general observance of restrictions on individual exploitation is not achieved, the only alternative is the total closure of all toheroa-beds to digging by the general public and placing the taking and sale of toheroa under absolute Government control—the means by which the rock-oyster resources of the North were saved from virtual extinction a generation ago. Whitebait. The most significant and usually the most important fact to be registered in an annual report on any fishery is the sum total of the catches made for the period in question. In connection with the whitebait fisheries of New Zealand this is obviously a difficult figure to arrive at, owing to the large but indefinite number and scattered distribution of those who take part in whitebait-fishing. It is mainly by means of information for which we are indebted to various whitebait dealers or to transport agencies that it is possible to obtain data for a quantitative statement. A certain unknown proportion of whitebait taken during each season is directly disposed of by the fishermen and never finds its way to any dealer or wholesale market. These limitations must be mentioned regarding the statement that follows, which is collated from information obtained principally by the local Inspectors of Fisheries at the various centres. It is believed that the figures giving the quantities of fish caught, though only approximating in varying degrees to the actual totals, may be taken with reasonable confidence for comparing the total output from the various rivers or districts from year to year.

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