Some Aspects of the Ecology of Lake Macquarie, N.S.W., with Regard to an Alleged Depletion of Fish. VIII. Trends of the Commercial Fish Catch and Management of the Fishery

Abstract

Although the total catch has fallen since 1922 the abundance of fish as measured by the catch per man has not. The total catch has dropped because fewer men are fishing. A red drop in the abundance of certain species, namely flathead, bream, luderick, and sea mullet, occurred between 1945 and 1947; the algal-feeding luderick and mullet regained their abundance by 1951, but the three ground fish had not regained their former abundance by 1957.

The trends of the monthly catch are similar in all years, the catch expectation being least reliable in November and most predictable in February.

Closing of the northern end of the lake to commercial fishing has resulted in a loss to the consumer of quantities of sea mullet and tailor, species which are fished ineffectively by amateur anglers. During the winter months netting in the northern part of the lake, except in certain bays which form nursery grounds for the young of several species, would have no injurious effect on the stocks.