Predicting potential fishing zones for pacific saury (Cololabis saira) with maximum entropy models and remotely sensed data

Abstract

Fishing locations for Pacific saury (Cololabis saira) obtained from images of the Operational Linescan System (OLS) of the U.S. Defense Meteorological Satellite Program, together with maximum entropy models and satellite-based oceanographic data of chlorophylla concentration (chl-a), sea-surface temperature (SST), eddy kinetic energy (EKE), and sea-surface height anomaly (SSHA), were used to evaluate the effects of oceanographic conditions on the formation of potential fishing zones (PFZ) for Pacific saury and to explore the spatial variability of these features in the western North Pacific. Actual fishing regions were identified as the bright areas created by a 2-level slicing method for OLS images collected August-December during 2005-2013. The results from a Maxent model revealed its potential for predicting the spatial distribution of Pacific saury and highlight the use of multispectral satellite images for describing PFZs. In all monthly models, the spatial PFZ patterns were explained predominantly by SST (14-16°C) and indicated that SST is the most influential factor in the geographic distribution of Pacific saury. Also related to PFZ formation were EKE and SSHA, possibly through their effects on the feeding grounds conditions. Concentration of chl-a had the least effect among other environmental factors in defining PFZs, especially during the end of the fishing season.