Summary: | Since 1995, a stratified random spring bottom trawl survey in the NAFO Regulatory Area of Div. 3NO was conducted by Spain. In 2001, the trawl vessel was replaced; so, the time series indices were transformed. The transformed entire series of mean catches, abundance, biomass and length distribution for Atlantic cod are presented for the period 1995-2000, and the no-transformed data for the years 2001-2003. The standard deviations are shown for abundance and biomass. In years 1998 and 2001 some extreme catches occurred, so we present the series with and withoout those data.The summed abundance and biomass based on conversion of the lenght frequencias are presented and compared to the estimates from the method used to convert the CPUE. The results are quite the same. The biomass presents a non-clear trend and the abundance an increasing since 1998 and a decreasing last year.
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