Atlantic cod and Yellowtail flounder indices from the Spanish Survey conducted in Divisions 3NO of the NAFO Regulatory Area

Since 1995, Spain carries out a stratified random spring bottom trawl survey in Div. 3NO of the NAFO Regulatory Area. In 2001, the trawl vessel and gear were replaced; so, the time series indices were transformed. The transformed entire series of mean catches, biomass and length distribution for Atl...

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Bibliographic Details
Main Authors: González-Troncoso, D. (Diana), Paz, X. (Xabier)
Format: Report
Language:English
Published: Centro Oceanográfico de Vigo 2008
Subjects:
Online Access:http://hdl.handle.net/10508/614
Description
Summary:Since 1995, Spain carries out a stratified random spring bottom trawl survey in Div. 3NO of the NAFO Regulatory Area. In 2001, the trawl vessel and gear were replaced; so, the time series indices were transformed. The transformed entire series of mean catches, biomass and length distribution for Atlantic cod (Gadus morhua) are presented for the period 1997-2000 and for Yellowtail flounder (Limanda ferruginea) for the period 1995-2000, and the both species no-transformed data for the years 2002-2007. For 2001, there are data from the two vessels. For Atlantic cod we can see a general decreasing in the biomass since the year 2002, although in 2006 the biomass is much higher because above all the catch of a simple town of almost 2 tons. In 2007 the biomass decreased, but the level is over the value in the period 2002-2005. For this species, an increase in the recruitment can be seen in 2004 and 2005, and in year 2007 the youngest length classes are much over the rest of the length classes. For Yellowtail flounder, there is no a clear trend since 1998; its indices are almost constant along this period.