Assessment of the International Fishery for Shrimp (Pandalus borealis) in Division 3M (Flemish Cap), 1993-2009

The development of the international shrimp (Pandalus borealis) fishery in NAFO Division 3M is described. Various indices show that even the stock was in high levels in 2006 and 2007 the lack of good recruitments in the last years and the progressive disappearance of the strong year classes 2001 and...

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Bibliographic Details
Main Author: Casas-Sánchez, José Miguel
Format: Report
Language:English
Published: 2009
Subjects:
Online Access:http://hdl.handle.net/10508/672
http://hdl.handle.net/10261/329090
Description
Summary:The development of the international shrimp (Pandalus borealis) fishery in NAFO Division 3M is described. Various indices show that even the stock was in high levels in 2006 and 2007 the lack of good recruitments in the last years and the progressive disappearance of the strong year classes 2001 and 2002 have caused a drastic decline of the stock. Although the effort in the last years was low due to high cost of oil and low marketing prize of shrimp, the increase of cod biomass (the most important predator of northern shrimp in 3M) has probably been the cause of the successive bad recruitments and resulting decline of the stock. The revised Nominal catches declined from 63970 tonnes in 2003 to 12889 tonnes in 2008. The catch in 2009 was only 2958 tonnes to 10 september. Noting the lack of reports on catch this figure might increase although is very unlikely that the catches exceed the 5000 tonnes. The results from ageing which is based on biological sampling showed a great number of five year olds per hour in 2007 proving the 2002 year-class to be very strong. However in 2008 this class year was barely represented and it was residual in 2009. The female biomass from EU survey was variable though without trends at a relative high level from 1998 to 2007 but in 2008 the estimated biomass decreased to levels prior 1998. In the 2009 EU survey the 3M biomass index was 2797 t, next to the lowest values estimated in the beginning of the EU survey series and confirming the decrease initiated in 2002. The female standardized CPUE could not be updated due to the lack and high uncertainty in the catch and effort data from 2009. Indices of recruitment from the commercial fishery (age 2 in numbers) are plotted against CPUE of 3+ two and three years later showing a significative relationship between them. The recruitment indices of both commercial fishery and EU survey show a very strong 2002 year-class followed by weak year-class since then. Considering the 15% of the maximum survey female biomass index as a limit reference ...