Aq Res State Trend
Possibly in overexploitation and overexploited.
[The GFCM methodology to provide stock status and management advice is described in the Appendix F of the Sixteenth Session of the Scientific Advisory Committee Report. See the Bibliography section.]
Habitat Bio
Climatic Zone: Temperate.
Aq Res Struct
Biological Stock: Yes
Stock assessment in the GFCM area of application is often conducted by management units, based on GSAs. This method does not ensure that the whole stock is assessed, since stocks may cover several different management units. In some cases, when there is scientific evidence of a stock spreading through different GSAs, as well as information on species from different GSAs, existing information is combined across GSAs. This is then defined as a “joint stock assessment of a shared stock”. The GFCM recommends that when scientific evidence of shared stocks exists, joint stock assessments should be attempted. A number of activities aimed at achieving a better definition of stock boundaries are currently being conducted at the GFCM level. [The State of Mediterranean and Black Sea Fisheries, 2016]
Exploit
This species is one of the most important commercial demersal species in the Alboran Sea. The fishing gear targeting this species is trawl. The trawlers operating since M’diq port target this species between Fnideq and Jebha, at depths between 70 m and 360 m. For Nador trawlers, they operate between Saidia and Jebha, at depths from 68 m to 470 m. For Al Hoceima trawlers, the limits of their trawling are from Sidi Hssaine to Jebha at depths from 18 m to 200 m. This fleet is multi-specific and targets shrimps in association with other groups of fishes. The deep-water rose shrimp represents only 5 percent of the total landings. All the units are in wood with a mean length of 22 m and with a mode of a conservation with ice. This fleet use many types of trawls but the most common trawls are:
- 2 m vertical open trawl, used to catch benthic species like soles, octopus and shrimps; and
- 5 m vertical open trawl, used to catch benthic and semi-pelagic species.
In 2019, in the Mediterranean ports, the coastal trawlers landed 73 commercial species. However, 20 of them constitute 96 percent of the catches. The most landed species are common octopus, Atlantic horse mackerel (
Trachurus trachurus), deep-water rose shrimp, axillary seabream
Pagellus acarne and
Trachinus spp.
Bio Assess
Data
Official trawlers landings and CPUE from 2003 to 2019 are used to run Biodyn. Landings length composition from 2017 to 2019 trawlers fleet, growth parameters (K = 0.39, Linf = 45 mm), length-weight relationship parameters (a = 0.0019 and b = 2.6113) (Garcia et al., 2009) and M scalar value of 0. 8 year-1 (Thomson and Bell) were used for length cohort analysis (LCA) and Y/R.
Assess Models
Type: Biomass-aggregated
BioDyn and LCA/Yield per Recruit
The estimation of the Alboran Sea deep-water rose shrimp was performed using analytical and global assessments approaches: LCA, Y/R and the global model BioDyn based on the Schaeffer production model.
Results
The B ratio Bcurrent/B0.1 is about 84 percent showing a low current biomass and the F ratio, Fcurrent/F 0.1, is 169 percent which shows an Fcurrent exceeding the F0.1 by 69 percent. The situation of the overexploitation observed in 2018 is still persistent in 2019.
Sci Advice
Reduce fishing mortality.
Sources
FAO. 2021. General Fisheries Commission for the Mediterranean. Report of the twenty-second session of the Scientific Advisory Committee on Fisheries, online, 22–25 June 2021. FAO Fisheries and Aquaculture Report No. 1347. Rome.
https://www.fao.org/3/cb7622en/cb7622en.pdfReport of the Working Group on Stock Assessment of Demersal Species (WGSAD). Online, 18–23 January 2021.
https://www.fao.org/gfcm/technical-meetings/detail/en/c/1412431/ Bibliography
FAO. 2020. The State of Mediterranean and Black Sea Fisheries 2020. General Fisheries Commission for the Mediterranean. Rome.
https://www.fao.org/3/cb2427en/cb2427en.pdfFAO. 2016. The State of Mediterranean and Black Sea Fisheries. General Fisheries Commission for the Mediterranean. Rome, Italy.
https://www.fao.org/3/i5496e/i5496e.pdfFAO General Fisheries Commission for the Mediterranean/Commission générale des pêches pour la Méditerranée. Report of the sixteenth session of the Scientific Advisory Committee. St. Julian’s, Malta, 17–20 March 2014/Rapport de la seizième session du Comité scientifique consultatif. Saint Julien, Malte, Malte, 17-20 mars 2014. FAO Fisheries and Aquaculture Report/FAO Rapport sur les pêches et l’aquaculture. No. R1102. Rome. 2015. 250 pp.
https://www.fao.org/3/i4381b/i4381b.pdf