Updated fishery indicators for shortfin mako shark (Isurus oxyrinchus) caught by the Portuguese pelagic longline fishery in the Indian Ocean: catch, effort and standardized CPUEs

Citation
Coelho R, Santos C, Rosa D (2020) Updated fishery indicators for shortfin mako shark (Isurus oxyrinchus) caught by the Portuguese pelagic longline fishery in the Indian Ocean: catch, effort and standardized CPUEs. In: IOTC - 16th Working Party on Ecosystems and Bycatch. IOTC–2020–WPEB16–15, Online, p 16
Abstract

This working document provides updated fishery indicators for the shortfin mako shark captured by the Portuguese pelagic longline fishery in the Indian Ocean, in terms of catches, effort and standardized CPUEs. The analysis was based on data collected from fishery observers, skipper's logbooks (self sampling) and official logbooks collected between 1998 and 2018. The CPUEs were analyzed for the Indian Ocean and compared between years, and were modeled with tweedie GLM models for the CPUE standardization procedure. In general, there was a large variability in the CPUE trends, with the standardized CPUEs relatively similar to the nominal trend and showing a general increasing trend, especially in recent years.