Yellowtail flounder, redfish (Sebastes spp) and witch flounder indices from the Spanish Survey conducted in Divisions 3NO of the NAFO Regulatory Area

Abstract

Since 1995, Spain carries out a spring stratified random bottom trawl survey in Div. 3NO of the NAFO Regulatory Area. Mean catches, biomass and length distribution for yellowtail flounder (Limanda ferruginea) are presented for the period 1995-2011, for redfish (Sebastes spp) for the period 1997-2011 and for witch flounder (Glyptocephalus cynoglossus) for the period 2002-2011. Yellowtail flounder does not show a clear trend since 1998; its indices are almost constant throughout this period, with a slight increase in the last three years. Redfish indices oscillate greatly over time, probably because the gear does not sample adequately aggregating pelagic species. There was a sharp increase in 2009, followed by a slight decrease in 2010 and a further increase in 2011. Good year classes have not been registered recently. Witch flounder is very scarce and also lacks a clear trend in the data series, being the values always poor. Recruitment was quite good at the beginning of the series but very poor in recent years.