AFTER months of struggling to send marine monitoring vessels to sea even with the assistance of the South African Navy, the Department of Agriculture, Forestry and Fisheries has given the go-ahead for the annual October-November multidisciplinary survey into the populations of anchovy and sardines.
The survey had been done each year since 1984, and is considered one of the longest uninterrupted time-series in the world, directly informing the calculation of the anchovy and sardine total allowable catches for the following year.
"This survey is of high priority for the department not only because the pelagic fishery is the largest in South Africa in terms of catch — about 400,000 tons annually — but also the second most important in terms of value, currently estimated at around R1bn," said Lionel Adendorf, spokesman for fisheries in the department.
Among other tasks, the survey will estimate the biomass and population length structure of anchovy, sardine, round herring, horse mackerel and meso-pelagic fish of the country’s sea-level jurisdiction. This is done by means of echo-integration, midwater trawling, and data collection for the description of distribution and behaviour patterns of these fish, including the influence of oceanographic variables on them.
Mr Adendorf said annual surveys were also required in terms of the department’s operational management procedure, developed to ensure sustainable utilisation of the small pelagic resources. The procedure is a set of rules or formulae used to set the annual total allowable catches given a prespecified set of inputs — in this case the annual estimates of recruitment strength of these fishes (estimated in May-June each year) and the adult population size determined in this survey.
During this voyage the research team will also collect fishes for age determinations and eggs of the species in question for biomass estimation and for mapping of spawning habitat.
Mr Adendorf said on Friday morning that the survey would be conducted by the country’s oldest research vessel, the Africana, which turned 30 this year. It was scheduled to leave the Western Cape on Friday for the annual six-week survey to determine the biomass of sardine and anchovy.
"What is even more remarkable about this 28-year uninterrupted record is the fact that this old lady, with its eight laboratories and three containerised labs, has carried out most of these surveys without fail and in the process, established these biomass surveys as one of the most credible, accurate and respected in the world," he said.
However, refurbishment of the research vessel during 2001 had prevented the Africana from being used for the survey for that season. Refurbishment included the upgrading of scientific equipment, fitting of a new gyro and radio, repair of the motors and the installation of a new deck crane for deploying sampling equipment — all at a cost of about R30m, he said.
Mr Adendorf said the management crew would be under the command of Capt Khwaedi Lotta Mabula of the navy, while the research team would be led by Kanakana Mushanganyisi. The expedition will return in December.
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