Roughhead grenadier (Macrourus berglax) in the waters off East Greenland: Distribution and biology

Abstract

The study focuses on distribution, catch rates and biological parameters of roughhead grenadier (Macrourus berglax) at East Greenland based on data from trawl surveys, longline surveys and commercial catches from the period 1994-2000. Roughhead grenadier was recorded at most fished stations at depths between 200 and 1 600 m. Catch rates and length frequencies varied both with gear, areas, depth and year. The observed patterns are at least partly caused by a separation of sex and length groups by depth strata. The catch rates were highest at depths between 1 000 and 1 500 m in the longline surveys and between 800 and 1 200 m in the trawl surveys. In both types of surveys the length distributions were dominated by a modal peak around 20 cm (PAF). Sex ratio changed with depth and length of 50% maturity (L50) was estimated to be at 16 and 29.5 cm for males and females, respectively. Estimate of potential fecundity from 25 specimens varied between 17-56 000 eggs per specimen.