FISH STOCKS IN RIVERS

Ashburton Guardian, Volume 68, Issue 139, 24 March 1948, Page 6

FISH STOCKS IN RIVERS

EROSION EFFECTS (P.A.) ' WELLINGTON, March 22. Research into the effects of erosion upon fresh-water fish stocks is being undertaken by the Government, and some important evidence has already been obtained from experiments carried out in rivers on the Molesworth Station, and near Wellington. It is known that severe flooding may have harmful effects, as may the Instability of river-beds, and the influence of these factors has already been considered in previous investigations by the fisheries section of the Marine Department. It is pointed out, however, that a distinction must he made between harmful effects which may occur from natural conditions and those arising from man-made accelerated erosion, which may be corrected. It is because of Ibis distinction that the department is carrying out longterm observations on rivers in areas where erosion is being checked and the land restored. j The Government hopes, through its ! investigations, to determine Ihe ex- | font of the improvement in conditions I affecting fish stocks which may fellow from the re-establishment of liio watersheds. As a. first slop in this work. a. preliminary survey has been made of 11 1 0 rivers on Molesworth station. which is now being managed by Ihe Lands and Purvey Department. Studies are also lining undertaken on methods of measuring the shift of river beds and the effects of such shifts on the fish fond. These investigations .axe being carried out in the Wellington district at present-, but tinwork will later he extended to other parts of New Zealand.