Analysis of biological and biochemical parameters of adult male spiny lobsters Jasus lalandii for identification of possible growth predictors

• Published in: Fisheries research 2021-11, Vol.243, p.106061, Article 106061
• Main Authors: Munian, Andre, Cockcroft, Andrew, Hoffman, Louwrens C., Auerswald, Lutz
• Format: Article
• Language: English
• Subjects: Moult; Palinurid; Physiological growth predictor; Reserve accumulation; Spiny lobster
• ISSN: 0165-7836; 1872-6763
• DOI: 10.1016/j.fishres.2021.106061

•Size and composition of hepatopancreas are potential predictors of male growth.•Organ size and lipid content shortly before annual moult are most suited predictors.•Higher values of these parameters correlate with faster subsequent moult increment.•More research is required to develop a quantitative predictor for growth prediction.•This growth prediction can be a novel component for stock assessment. Biological body parameters of adult male West Coast rock lobsters, Jasus lalandii, of commercial size were analysed over two years to determine reserve accumulation during two moult (i.e. growth-) cycles. Two fishing areas were compared that were historically known for fast- and slow growth, respectively. In addition, setagenic development for moult stage determination and the biochemistry of the hepatopancreas were investigated from the fast growth area. This information was intended to confirm previously proposed predictors of annual male moult increment and identify potential new ones. Annual moult increments in these areas were determined from tag-and-recapture studies, including the seasons for which reserve accumulation was analysed. Data from the present study were not robust enough to confirm previously proposed predictors from peak accumulation months (March – May). Data arranged per moult stage were also unsuitable for prediction. Further results analysis, however, identified a subset of data that are potentially more useful: Hepatosomatic index HSI (+ 6 %), lipid content (+ 9 % ww, + 12 % wD) and lipid per whole hepatopancreas (+ 24 %) are all significantly higher in July 2011 than in July 2010, the last sampled months before the respective annual moult. These differences correlate with a 26 % (0.7 mm) faster growth during subsequent moult in 2011 than in 2010. Aspects of hepatopancreas lipid metabolism in the months prior to moult have therefore the potential to provide simple and robust predictors of growth in adult male J. lalandii. However, more research is required that also includes the months adjacent to July in more than one area and for a longer period than two years.