Results for Greenland halibut, American plaice and Atlantic cod of the Spanish survey in NAFO Div. 3NO for the period 1997-2016.

• Main Authors: González-Troncoso, Diana, Gago-Fernández, Ana, Nogueira, Adriana, Román-Marcote, Esther
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2017
• Subjects: Centro Oceanográfico de Vigo; NAFO Divisions 3NO; Pesquerías; Survey; Greenland halibut; American plaice; Atlantic cod; natural resources; biological sampling; Greenland; atlantic cod; Gadus morhua
• Online Access: http://hdl.handle.net/10508/11194; http://hdl.handle.net/10261/327785

Greenland halibut (Reinhardtius hippoglossoides), American plaice (Hippoglossoides platessoides) and Atlantic cod (Gadus morhua) indices from the bottom trawl survey that Spain carries out in Spring since 1995 in Div. 3NO of the NAFO Regulatory Area are presented. Biomass, stratified mean catches and mean number per tow for the three species are presented since 1997, year in which the survey extended the depth strata. Mean catch per tow, length distribution and age distribution are presented for the last five years (2012-2016). Greenland halibut biomass and abundance estimates presented a decreasing trend since 1999, cut in year 2007 with an increase, reaching in 2009 the highest value in the series. In 2011 the biomass drops under the 2008 value, being stable since then until 2014 with a slight increase in 2015 and 2016. In last years it can be seen a presence of juveniles, mainly in 2004, but the greatest lengths have failed, although in 2009 there is a quite good presence of individuals of ages 6-7 and in 2010 between 5-7. In 2011-2016 the presence of all ages is poor, although in 2015- 2016 an increase in the range of the length can be seen with regards to last years. For American plaice we can see a stable trend from 1999 to 2015, reaching a maximum of mean catch and number in 2006, and a severe decline in 2016. The greatest recruitment in the presented series occurred in 2004 and we can follow their mode along the years. No good recruitments were seen since then. In 2016 no ALK are available, but all the length ranges are poor. For Atlantic cod, it can be seen a low biomass until 2008, being higher and variable since then, reaching a historical maximum in 2014. From 2014 to 2016, biomass decreased by a third. In 2007-2008 the youngest length classes were much over the rest of the length classes. With the 2006 cohort the series reaches the maximum number of its historical values at five years in 2011. There have been no good recruitments since 2009, although in 2015 and 2016 a discrete presence of ...