A fp7 Project: Management and Monitoring of Deep-sea Fisheries and Stocks wp2 – Template for Case Study Reports Case study 2 demersal deep-water mixed fishery Pascal Lorance, Ifremer, Nantes (coord.)
Section 3.Review of stock assessments carried out thus far
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- Black scabbardfish in V, VI, VII, XII
- Greater forkbeard
- Portuguese dogfish and leafscale gulper shark
- 3.1.2.How is the frequency of assessments linked to the advisory and management cycle
Section 3.Review of stock assessments carried out thus far3.1. General overview3.1.1. Overview of previous assessments:Roundnose Grenadier (Coryphaenoides Rupestris) in Vb, VI, VII, XIIb
Black scabbardfish in V, VI, VII, XIINo model of population dynamic was used for assessments 2008-2010. Some work has been done to use CPUE from the French fleet of deep-water trawlers as an indicator of trends in the deepwater fishery. In the past, assessments were done using De Lury and Schaefer production models (Basson et al. 2002).
Greater forkbeardNo quantitative assessment was carried out in 2008, 2009.
Portuguese dogfish and leafscale gulper sharkBoth stock are merged into a single “siki sharks” stock. The term “siki” is used to describe the combination of leafscale gulper shark and portuguese dogfish. Although these species have different biological traits, it has been necessary for ICES to combine them for assessment purposes. This is because landings data for both species were combined for some of the main countries for most of the time since the beginning of the fishery. The term “siki” as used here does not have the same meaning in French commercial fisheries, where it encompasses all commercially exploited deepwater sharks. No assessment has been carried out since 2006. Some work has been done to use CPUE as an indicator of trends in the deepwater fishery. An exploratory model for Portuguese dogfish only was presented at the ICES WKDEEP benchmark workshop in 2010.
Assessment using De Lury and Schaefer production models were trialled in the early 2000s for both Portuguese dogfish and leafscale gulper shark combined (Basson et al. 2002). 3.1.2.How is the frequency of assessments linked to the advisory and management cycle?Fisheries for deep-water species in the NE Atlantic were largely unregulated from their commencement in the 1970s (blue ling) or the 1980s (other deep-water species) to the early 2000s. Following repeated ICES advice that most stocks were “outside safe biological limits,” that “fishing effort on specified stocks should be reduced” while on others “fishing should not be allowed to expand faster than the acquisition of information necessary to provide a basis for sustainable exploitation” and that “new fisheries should be permitted only when fisheries expand very slowly, and are accompanied by programs to collect data which allow evaluation of stock status,” it was not until January 2003 that the EU introduced biennial TACs for deep-water species, including roundnose grenadier. As a first step towards effort management, a vessel licensing scheme with aggregate power and capacity of deep-water fishing vessels capped to levels observed in the years 1998–2000 was implemented. The ICES advice for deep-water species stocks is delivered every second year. The mangement cycle is consistent with the delivery of ICES advice as TACs a set every second yerar since 2003. TACs levels were kept the same for the two subsequent years in 2003-2006 then from 2007 some TACs were adjusted annually although set in a TAC regultion valid for two years (see table 6.2.1). This derived from the rule of limiting TAC changes to 15% per year. Since 2009, the EU TACs for blue ling are set annual in the general TAC regulation (council regulation (EC) No 43/2009 of 16 January 2009) because the fishing opportunities for this species depend on the outcome of the annual negotiations between the EU and Norway (council regulation (EC) No 1359/2008 of 28 November 2008). As a result the scientific advisory cycle and the management cycle are no longer consistent for blue ling. The EU TAC and national quotas from member countries apply to all vessels in EU EEZ and to EU vessels in international waters. For roundnose grenadier and black scabbardfish, ICES recommends that catches should be constrained to 50% of the level before the respective expansions of the fisheries. For greater forkbeard, ICES advice state that the landings of this species are mainly bycatch from traditional demersal trawl and longline fisheries targeting species such as hake, megrim, monkfish, ling, blue ling, etc. Fluctuations in landings are probably the result of changing effort on different target species and/or market prices and are not necessary linked with changes in the resource abundance. The species should not be managed in a single species context and any advice should take into account advice on other species/fisheries. For all the above species, ICES recommends those fisheries should not be allowed to expand unless it can be demonstrated that they are sustainable. There is no management objective for the above species. For deepwater sharks, no assessment was performed in recent years and advice and management are based on the perception of the state of the stocks by the members of the WGEF working group from trends in CPUE. In 2006, ICES advised that no target fisheries should be permitted unless there were reliable estimates of current exploitation rates and stock productivity. ICES advised that the TAC should set to zero for the entire distribution area of the stocks and additional measures should be taken to prevent by catch of portuguese dogfish and leafscale gulper shark in fisheries targeting other species. In 2008, based again on information from CPUE, Portuguese dogfish and leafscale gulper shark stocks were considered to have declined to low levels and ICES recommended a zero catch. Portuguese dogfish and leafscale gulper shark were considered depleted despite the fact that the rates of exploitation and stock sizes of deep water sharks could not be quantified. The TACs are not restricted to the two species of siki sharks but include the following species of deep-water sharks (EC regulation No 1359/2009 of the council of 28 November 2008): Portuguese dogfish, leafscale gulper shark, birdbeak dogfish (Deania calceus), kitefin shark (Dalatias licha), greater lantern shark (Etmopterus princeps), velvet belly (Etmopterus spinax), black dogfish (Centroscyllium fabricii), gulper shark (Centrophorus granulosus), blackmouth dogfish (Galeus melastomus), mouse catshark (Galeus murinus), and Iceland catshark (Apristurus spp). Directory: lib -> exe exe -> Homework Problem Set 3 Solution I. Reading Assignment exe -> System Modeling Assessment & Roadmap wg exe -> Artemis-2011-1 decision and platform support for model‐based eVolutionary development of Embedded systems Date of preparation exe -> Date: January December 2011 Java 5 Language psm for dds (dds-java) exe -> Notes on bcd by N. 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