Reaching New Depths: Predicting bathymetric shifts of marine commercial fish species.

Jané Salazar Mcloughlin

Marine ecosystem changes are often the result of overexploitation and increasing ocean temperature due to anthropogenic climate change. Marine commercial fish species are an important part of social and ecological communities both in terms of food and economic security and ecosystem functioning and services. Peer reviewed literature on commercial fish species that have shifted or not due to climate change was gathered with the goal being to use this information, together with their life-history traits, to develop models that may help predict the probability of shifting for a given trait. It was found that van Bertalanffy growth rate (K y-1) and Length-at-maturity (Lmat cm) are key determinants in predicting future bathymetric shifts whereby low K and high Lmat values increases the odds of increasing bathymetric distribution. The full multinomial model predicted with ~71% accuracy and the model validation provided a cross validation accuracy of 64%, and Area Under Curve (AUC) score of 0.84, which shows that the model has excellent predictive performance given a random sample. The result of this study provides new information that will be useful to evaluate fisheries management options under climate change. Understanding species responses to a changing climate is a fundamental aim of scientists to predict population viability under climate change, this is especially important for future food and economic security.