Seasonal and annual growth rates in the Antarctic fish Notothenia coriiceps Richardson

Growth in Antarctic fishes is assumed to be seasonal but quantitative data are scarce. Growth rates in juvenile Notothenia coriiceps, a typical Antarctic fish, were measured using mark–recapture techniques and found to be greater when periods of liberty included summer and early autumn months and least when liberty was restricted to winter months. Weight specific growth rates ranged from −0.08–0.26% body weight day−1. Year class analysis and cohort analysis were attempted on serial samples of the population but proved ineffective methods for detecting seasonal growth in these slow growing fishes. A tentative description of the seasonal growth profile is proposed. Seasonality in growth indicates that some form of growth limitation is active; competing hypotheses of temperature and resource limitation are discussed. Annual growth rates in three year classes showed an inverse relationship with age. Parameters of the Pütter-von Bertalanffy growth equation were estimated. Comparison with other studies show the growth characteristics of N. coriiceps differ with geographical location but have not changed substantially at Signy Island over the past 25 years.

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