Results for Greenland halibut, American plaice and Atlantic cod of the Spanish survey in NAFO Div. 3NO for the period 1997-2011

• Main Authors: González-Troncoso, Diana, Román-Marcote, Esther, Paz, Xabier
• Format: Report
• Language: English
• Published: 2012
• Subjects: Pesquerías; Centro Oceanográfico de Vigo; Greenland; atlantic cod; Gadus morhua; North Atlantic; Northwest Atlantic
• Online Access: http://hdl.handle.net/10508/763; http://hdl.handle.net/10261/327811

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. Mean catch per town, biomass, length and age distributions for the three species are presented since 1997, year in which the survey extended the depth strata. In 2001, the R/V Vizconde de Eza replaced the C/V Playa de Menduíña in the execution of the survey. We present the transformed to the R/V Vizconde de Eza series for the period 1997-2000, and the original obtained data for the period 2002-2011. In 2001, there are data from the two vessels. Greenland halibut biomass and abundance estimates present a decreasing trend since 1999, cut in year 2007 with a slight increase and a high increase since 2008, reaching in 2009 the highest value in the series. In 2011 the biomass drops under the 2008 value. 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 the presence of all the ages is poor. For American plaice we can see an increasing trend along the whole period, reaching a maximum of biomass and number in 2006, following by the 2008 indices, cut in 2009 with a decrease in the indices, remains in a lower value than in the year 2003 following with an increase in 2010-2011. The greatest recruitment in the presented series occurred in 2004 and we can follow their mode along the years, reaching its maximum in 2008. For Atlantic cod it can be seen a general decreasing in the biomass between 2002 and 2005 and an increasing since then, especially in 2006 and, higher, in 2009-2011. For this species, an increase in the recruitment can be seen in 2004 and 2005, and from 2007 the youngest length classes are much over the rest of the length classes. With the 2006 cohort the series reaches the maximum ...