Fisheries and Resources Monitoring System

EspañolFrançais
Common octopus - Dakhla stock (26°N - 21°N)
Marine Resource  Fact Sheet
CECAF Scientific advice 2016
Common octopus - Dakhla stock (26°N - 21°N)
Fact Sheet Citation  
Poulpe (Octopus vulgaris) - Stock Dakhla (26°N - 21°N)
Owned byFood and Agriculture Organization (FAO) – More
Related observationsLocate in inventorydisplay tree map
 
Species:
FAO Names: en - Common octopus, fr - Pieuvre, es - Pulpo común

Fishery Indicators
Production: Catch
Geographic extent of Common octopus - Dakhla stock (26°N - 21°N)
Main Descriptors
Considered a single stock: Yes        Spatial Scale: Local
Management unit: Yes        Reference year: 2012
 
 
Biological State and Trend
State & Trend Descriptors
PartnerFIRMS
Exploitation rateFcur/F0.1 = 112%; Fcur/FMSY = 101%Not applicable
Abundance levelBcur/B0.1 = 58% ; Bcur/BMSY = 63%Not applicable
Aq Res State Trend
Exploitation stateOverexploited

Fcur/F0.1: Ratio between the observed fishing mortality coefficient during the last year of the series and F0.1.
Fcur/FMSY: Ratio between the observed fishing mortality coefficient during the last year of the series and the coefficient that would give a maximum sustainable yield over the long term.
Bcur/B0.1: Ratio between the estimated biomass for the last year and the biomass corresponding to F0.1.
Bcur/BMSY: Ratio between the estimated biomass for the last year and the biomass corresponding to FMSY.
Unless otherwise indicated, the indicators were based on the Schaefer dynamic production stock assessment model.
Habitat and Biology
Climatic zone: Temperate; Tropical.   Bottom type: Hard rocky bottom; Coral reef; Seagrass.   Depth zone: Coastal (0 m - 50 m); Shelf (50 m - 200 m).   Horizontal distribution: Neritic.   Vertical distribution: Demersal/Benthic.  

Water Area Overview
Spatial Scale: Local

Geo References
Resource Structure
Considered a single stock: Yes


Three different octopus stocks have been identified in the North CECAF sub-region since the first assessment Working Group held in 1978:
- Dakhla Stock (26 °N-21 °N)
- Cap Blanc Stock (21 °N-16 °N)
- Senegal-Gambia Stock (16 °N-12 °N)
This stock identification was based on fishery data that have recently been confirmed using more accurate fishing information, using the vessel monitoring system (VMS) as well as genetic analyses.
Exploitation
 
Fishery Indicators
TypeMeasureValueUnitTime period
ProductionCatch 75602tonnes1990
Catch 111623tonnes1991
Catch 90744tonnes1992
Catch 99987tonnes1993
Catch 87254tonnes1994
Catch 78485tonnes1995
Catch 67626tonnes1996
Catch 50081tonnes1997
Catch 71235tonnes1998
Catch 92584tonnes1999
Catch 107373tonnes2000
Catch 80497tonnes2001
Catch 56781tonnes2002
Catch 25648tonnes2003
Catch 17963tonnes2004
Catch 34208tonnes2005
Catch 28747tonnes2006
Catch 30298tonnes2007
Catch 43491tonnes2008
Catch 37667tonnes2009
Catch 27684tonnes2010
Catch 20865tonnes2011
Catch 27534tonnes2012
Assessment
 

Assessment year: 2013
The CECAF Working Groups have adopted the following Biological Reference Points (BRPs):
- Limit Reference points: BMSY and FMSY
- Target Reference Points: B0.1 and F0.1
Stock status is assigned based on current estimates of fishing mortality (Fcur) and biomass (Bcur) relative to these target and limit reference points (Bcur/BMSY, Fcur/FMSY, Bcur/B0.1, Fcur/F0.1). The results from the stock assessment of this stock are found under the “Biological state and trend section”.
Assessment Model
Type:  Biomass-aggregated
Schaefer dynamic production model

For the assessment, series of total catches from 2001 to 2012 in tonnes in the zone between 26°N and 20°50’ N for the three Moroccan fleet segments were used. The Working Group used two different series of abundance indices: the CPUEs of the Moroccan deep-sea cephalopod fishery and the abundance indices of trawling surveys conducted in the area between Cap Boujdor and Lguira. For the model fit, the CPUE series was used, Moreover, the results used were those obtained from the abundance indices (scientific surveys) as they better represent the stock biomass.
Overall Assessment Results

The model provides a good fit between catch and the abundance indices from the scientific surveys as they better represent the actual state of the stock (Figure 5.3.4a of FAO, 2016b) [see also "Biological state and trend"]. The current biomass corresponds to 58 percent of the target biomass B0.1 and the fishing effort for the last year is almost at the same level as that which would produce the biomass B0.1(Table 5.3.4a of FAO, 2016b) [see also "Biological state and trend"].
Scientific Advice

It is recommended that fishing effort should not exceed the level of 2012.
Management
Management unit: Yes
Source of information
 
FAO. 2016a. Fishery Committee for the Eastern Central Atlantic, Report of the seventh session of the Scientific Sub-Committee, Tenerife, Spain, 14–16 October 2015 / Comité des pêches pour l’Atlantique Centre-Est Rapport de la septième session du Sous-Comité scientifique. Tenerife, Espagne 14-16 octobre 2015. FAO Fisheries and Aquaculture Report / FAO Rapport sur les pêches et l’aquaculture No. 1128. Rome, Italy.  Click to openhttp://www.fao.org/3/a-i5301b.pdf
FAO. 2016b. Report of the FAO/CECAF Working Group on the Assessment of Demersal Resources – Subgroup North. Fuengirola, Spain, 18–27 November 2013. / Rapport du Groupe de travail FAO/COPACE sur l’évaluation des ressources démersales – Sousgroupe Nord. Fuengirola, Espagne, 18-27 novembre 2013. CECAF/ECAF Series/COPACE/PACE Séries. No. 15/77. Rome, Italy/Italie.  Click to openhttp://www.fao.org/3/a-i5114b.pdf
Bibliography
 
All references to figures, tables and bibliography in the text are found within the source of information.
powered by FIGIS  © FAO, 2019
Powered by FIGIS
crawl