This study focuses on the Chamsocephahus gunnari stock around South Georgia. The principle aims are, first, to assess current and past biomass and recruitment levels and, second, to analyse the relationship between the spawning stock and number of recruits. A conventional VPA and an ad hoc tuning method are used to estimate biomass levels and fishing mortality for the period 1971/72 to 1988/89. VPA-estimates of recruitment levels are used to investigate the degree of variability and the likely statistical distribution of recruitment. Data obtained during the UK/Polish survey around South Georgia in March 1989, were included in the study.
Results indicate that the current biomass level of the C. gunnari stock around South Georgia is only about 25% of the estimated peak biomass and that catch levels observed in recent years cannot be sustained. There is no clear relationship between the size of the spawning stock and recruitment, which is highly variable
The Status of the Champsocephalus gunnari Stock in the South Georgia Area
Número de documento:
WG-FSA-89/8 Rev. 1
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