Update of standardized CPUE of blue shark, Prionace glauca, caught by the Uruguayan longliners in the southwestern Atlantic Ocean (1992-2012) | Bycatch Management Information System (BMIS)

Source URL

https://www.iccat.int/en/pubs_CVSP.html

Citation

Forselledo R, Mas F, Pons M, Domingo A (2016) Update of standardized CPUE of blue shark, Prionace glauca, caught by the Uruguayan longliners in the southwestern Atlantic Ocean (1992-2012). ICCAT Collect Vol Sci Papers 72:1124–1133

Abstract

This study presents an update of the standardized catch rate of blue shark, Prionace glauca, caught by the Uruguayan longline fleet in the Southwestern Atlantic using information from logbooks between 1992 and 2012. Because of the large proportion of zeros catches (36%) the CPUE (catch per unit of effort in weight) was standardized by Generalized Linear Mixed Models (GLMMs) using a Delta Lognormal approach. The independent variables included in the models as main factors and ﬁrst-order interactions were: Year, Quarter, Area and Sea Surface Temperature. A total of 10,531 sets were analyzed. The standardized CPUE series of blue shark caught by the Uruguayan longline fleet shows a fairly constant trend from 1992 to 2009 and a pronounced increase from 2010 onwards.