Metabolism, Swimming Performance, and a Behavioural Syndrome in Schoolmaster Snapper (Lutjanus apodus)

Abstract

Commercial overexploitation and climate change can alter the physiology and behaviour of affected marine organisms, although depending on the environment, species, and severity, intraspecific phenotypic response to such changes can vary greatly. Under the Pace-Of-Life Syndrome (POLS) hypothesis, behaviour, physiology, and life history traits can be linked and thus affected both directly and indirectly by selection targeting any aspect of behavioural physiology. However, such links are often understudied in tropical marine fish, with work needed to better understand the impacts of fisheries and climate change on fish stocks. Moreover, tropical regions have greater reliance on fisheries, thus investigations should focus on species with economic value to ensure social benefits. This study aimed to partially address this need by measuring the behaviour (boldness and activity), metabolism and swimming performance (Ucrit) of schoolmaster snapper Lutjanus apodus in Eleuthera, The Bahamas. I found a strong positive correlation between boldness and activity with high repeatability of behavioural metrics, and two groupings present, consistent with ‘proactive’ and ‘reactive’ behavioural types. Proactive and reactive behavioural types also differed significantly in terms of Ucrit values with reactive individuals showing increased swimming performance. No significant differences were found between behavioural types for any of the metabolic proxies. These results present preliminary research into the links, or lack thereof, between behaviour and physiology in an economically valuable tropical marine fish. Further investigation into this potential model species would allow refinement of predictions relating to the success of proactive/reactive types under overexploitation and climate change.