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APPENDIX The Distribution and Quantities of the Four Most Important Species In the maps that follow, the distribution of the four most important commercial species is indicated—namely, Snapper, Tarakihi, Hapuku, and Blue Cod. The range of distribution shown in ■each case is based on the incidence of the species in the catch of commercial boats. The activities of the commercial boats are in turn bound up with such factors as suitable harbours in relation to nature and extent of fishing-ground, market demand for the species, and quantities available. Thus the bulk of the fishing is done from east coast ports, where known grounds are more extensive and where there is more shelter. Because of the exposure to the prevailing westerly weather, lack of shelter and suitable harbour facilities, the west coast of New Zealand generally is only lightly fished. Snapper, the most abundant species, is mainly caught by trawl and Danish-seine, though a significant quantity is caught in set and drag nets and by lines. The range of this species in commercial quantities is remarkable in that it is more clearly defined than is the case of the other species discussed. Snapper form the principal species in the catch in the north-western part of the South Island, the west coast of the North Island, and the east coast of the North Island to just south of East Cape. Tarakihi is caught by the same methods as snapper, trawling being the most important. The principal tarakihi fisheries are on the east coast south of East Cape, though significant quantities are taken on the» Auckland east coast and in Bay of Plenty and a smaller quantity on the west coast of the South Island. Hapuku or groper is mainly a line-caught fish associated with rocky bottom and a depth of about •60 fathoms. The distribution is general where the bottom is suitable ; it forms a principal fishery in Cook Strait and on the rocky parts of the east coast of the South Island. Blue cod, also a line-caught fish associated with rock bottom, is principally a southern fish, with the main fishery about Foveaux Strait and Stewart Island. Though represented in the North, the species in these waters is not numerous or of the same consistent size that is to be found in South Island waters. The total annual production of each of these species since 1936 is shown in the accompanying graph. Snapper-and tarakihi, being principally trawl caught, show a depression during the war years while steam-trawlers were otherwise engaged. The addition of modern steam-trawlers to Wellington and Port Chalmers on the principal tarakihi grounds accounts for much of the increase in this species. The limit imposed by market demand for this species is partly responsible for the fiattening-off of this line during 1948. Hapuku, a line-caught fish, shows a slight rise in post-war years, due mainly to the re-engining and replacement of a considerable number of the boats. The rise shown in the Blue Cod catch during 1946-48 is due mainly to the Chatham Islands fishery, which was only lightly fished during the war years.

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