White anglerfish (Lophius piscatorius) in northern Iberian waters and northernmost Atlantic areas: weight-length relationships and other population parameters from a decade of research

Abstract

The white anglerfish (Lophius piscatorius) is a bottom-living and commercially important species for European fisheries (∼38.000 t in Atlantic waters in 2015). Weight-length relationship, weight conversion factors and condition factor for this species are estimated from a decade (2006-2015) in northern Iberian waters (ICES Div. VIIIc-IXa, southern stock) and in Celtic Seas (ICES Div. VIIb,c,h,j,k, northern stock). A total of 7219 white anglerfish were collected from commercial landings and research surveys and the total length (Lt), total weight (Wt), gutted weight with liver (Wgl) and gutted weight (Wg) were obtained. The weight-length relationships for the combined sexes were: Lt = 0.025 Wt2.853; Lt = 0.02 Wgl2.868; Lt = 0.024 Wg2.861 in Div. VIIIc-IXa, and Lt = 0.027 Wt2.826; Lt = 0.023 Wgl2.825; Lt = 0.023 Wg2.816 in Div. VIIb,c,h,j,k. The commercial landings of this species are available in gutted weight, and therefore the conversion factor (total-gutted weights) was also estimated. All these results can be used in the annual assessment of the state of both stocks in the ICES working group. The condition factor was estimated along the year for immature and mature individuals of each sex and it could provide additional information regarding the spawning season. The results are compared to the previously estimated in other studies.