Publication Abstract

The utility of fisheries-independent trawl surveys for evaluating spatial and temporal trends in the relative abundance of Northeast Atlantic spurdog (Squalus acanthias)

The utility of fisheries-independent trawl surveys for evaluating spatial and temporal trends in the relative abundance of Northeast Atlantic spurdog (Squalus acanthias)

S. R. McCully, J. A. A. De Oliveira, H. Dobby, S. Beggs and J. R. Ellis

Spurdog is a frequently captured shark in various otter trawl surveys in the ICES area. Here we examine the size-frequencies and sex ratios of spurdog taken in Scottish surveys in the North Sea and off Northwest Scotland, English surveys in the North, Celtic and Irish Seas, and Northern Irish surveys in the Irish Sea. The spatial and temporal distributions of spurdog landings in commercial landings were examined to appraise the suitability of the timing of the surveys in each area. Surveys in Northwest Scotland and the northern parts of the Irish Sea captured smaller-sized spurdog, and mature female spurdog were often captured in the Irish Sea. Spatial and temporal patterns in the relative abundance of spurdog are discussed. Given the implementations of a zero TAC for Northeast Atlantic spurdog (with some allowance for bycatch) in 2010, fishery-independent surveys will be of increasing importance if stock recovery is to be assessed.

Reference:

S. R. McCully, J. A. A. De Oliveira, H. Dobby, S. Beggs and J. R. Ellis (2010) The utility of fisheries-independent trawl surveys for evaluating spatial and temporal trends in the relative abundance of Northeast Atlantic spurdog (Squalus acanthias). ICES CM 2010/E

S.R. McCully*, J.A.A. De Oliveira*, H. Dobby, S. Beggs and J.R. Ellis*

ICES Annual Science Conference 2010: ICES CM 2010/E