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Nephrops norvegicus is a burrowing decapod with patchy distribution. In the North and Northwest Iberian shelf and upper slope, it is a by-catch species of the bottom trawl mixed fisheries. The International Council for the Exploration of the Sea (ICES) assesses four Nephrops stocks in the area: North Portugal, West and North Galicia and Cantabrian Sea. From a relatively buoyant Nephrops fishery in the period 1975–1989, with annual average landings of 1225 t for the entire area, the landings declined substantially to 270 t in 2000. The general trend for the region is a decline of more than 60% in the catch-per-unit-effort in the last decade. These indicators make the status of the Nephrops stocks a matter of concern. In this paper, trends in the time series of Nephrops fishery data are described and evidence from age-based assessment is given of sharp declines in stock biomass and recruitment. [Copyright &y& Elsevier]

Abstract: Nephrops landings from Spanish trawlers in Porcupine bank (West of Ireland) have decreased a 90% in the last 25 years. With the aim of studying the causes of this situation, the relation between CPUE (1979–2005) and several environmental and population factors is investigated through a monthly time series approach. Discards in the fishery are negligible. As LPUE time series exhibits a seasonal pattern, a seasonal decomposition of the CPUE is carried out showing a decreasing trend from 1982 to 2003. The LPUE series is modelized resulting in an autoregressive and moving average model (ARMA) that highlights a monthly positive and seasonal negative autodependence. Population and environmental parameters (i.e. recruits per unit effort “RPUE”, sex ratio, ovigerous females’ proportion, North Atlantic Oscillation index “NAO” and Atlantic Multidecadal Oscillation index “AMO”) were tested at different lags as independent variables of the ARMA model. The outcoming multivariated dynamic ARMA model states that CPUE is positively related to sex ratio lagged by 8 years and negatively related to the NAO index from 6.5 years before. In accordance with those results 1978, 1983, 1986, 1989, 1992, 1995 and 1996 Porcupine Bank stormy, warm and wet conditions would be linked to the 1984, 1989, 1993, 1996, 1998, 2001 and 2003 Nephrops CPUE low values. Those results show an expectable model in relation to Nephrops density in which environmental conditions would have a relevant role. [Copyright &y& Elsevier]

Abstract: Within the frame of an international tagging program which has been carried out since 1995, movements of black and white anglerfish (Lophius budegassa and L. piscatorius) in Southern European waters were studied. This is the first large-scale study on movements of tagged black anglerfish. A total of 877 black anglerfish (6–88cm total length) and 1326 white anglerfish (15–137cm total length) were tagged. Times at liberty ranged from 1 to 665 days, with recapture rates of 21 (2.4%) and 50 (3.8%), respectively. A description of our tagging procedures is presented, together with the influences of the gear used, fish length and area of tagging on recapture rates. The type of fishing gear was the main factor affecting recapture rates. Fish length was neither related to the displacement distance nor to the time at liberty while the displacement distance was related to the time at liberty. Recapture locations suggested that movements occurred both in- and offshore. The largest displacement recorded was 408km of a black anglerfish from southern to northern Bay of Biscay. The movements of the anglerfish indicate a mixing between northern and southern populations which may have strong implications for the current geographical boundaries of the stocks from a management perspective. Here, movement of white anglerfish between the Le Danois Bank and the Cantabrian continental shelf is reported for the first time. [Copyright &y& Elsevier]