The experience of rebuilding the South African hake resource following its depletion by foreign fishing fleets in the 1960s and 1970s, and the management of the deep-sea trawl fishery since the 1980s, is documented in an important scientific Technical Paper published earlier this year.
“Rebuilding of Marine Fisheries” was jointly prepared by the Food and Agriculture Organization of the United Nations (FAO) and the Fisheries Expert Group of the IUCN Commission on Ecosystem Management. The paper presents an extensive global review of the concept and practice of fishery stock rebuilding and includes a number of case studies on rebuilding initiatives that have taken place in different parts of the world for a variety of fisheries.
Leading South African scientists Johann Augustyn, Andrew Cockroft, Janet Coetzee, Deon Durholtz and Carl van der Lingen contributed a chapter to the Technical Paper. Johann Augustyn is secretary of the South African Deep-Sea Trawling Industry Association and his co-authors are fisheries scientists working for the Department of Agriculture, Forestry and Fisheries. Their chapter is entitled “Rebuilding South African fisheries: three case studies”. It documents efforts to rebuild the deep-water hake, sardine and west coast rock lobster resources which have been subject to varying levels of depletion over time and achieved different degrees of success as a result of stock rebuilding efforts.
In the case of the hake resource, the incursion by foreign fishing fleets in the 1960s led to stock depletion and declining declining catch rates by 1972. The turning point was the declaration by South Africa of an exclusive economic zone (EEZ) in November 1977. This resulted in the exclusion of foreign vessels from local waters and is considered to be the start of the process of rebuilding the hake resource. Individual fishing rights or quotas were allocated for the first time in 1979.
Since 1990, the hake fishery has been managed by an operational management procedure (OMP), a system that utilises industry catch records and the results of annual research surveys and applies a set of pre-determined harvest control rules to recommend an annual total allowable catch.
The case study documents how the hake OMP has adapted over the years to accommodate fluctuations in the hake stock, changing fishing practices and new knowledge about the behavior of the stock. For example, in 2006 stock assessments indicated that several years of poor recruitment for both deep-water (Merluccius paradoxus) and shallow-water hake (Merluccius capensis) had resulted in a decline in biomass. At the time, the shallow-water hake stock was in relatively good condition, but there were concerns that the deep-water hake stock had declined to below maximum sustainable yield (MSY), a measure that aims to maintain a balance between the natural growth of a stock and the volume removed from it by fishing.
The case study demonstrates that the OMP has yielded positive results, with the decline in the spawning biomass of deep-water hake having reversed and stocks of shallow-water hake being fished well above MSY.
Today stocks of both deep water hake and shallow water hake are considered to be “above MSY”. This means the growth of the stocks is in balance with fishing activity and current catch levels are sustainable over time.
An increase in the annual total allowable catch is expected for the 2019 fishing season which begins on 1 January 2019.