Cuttlefish

Sepia officinalis

Method of production — Caught at sea
Capture method — Hook & line
Capture area — Eastern Central Atlantic (FAO 34)
Stock area — All Areas
Stock detail
Picture of Cuttlefish

Sustainability rating rating under review info

Sustainability overview

Sepia officinalis has been assessed as being of Least Concern by IUCN - The World Conservation Union. Cuttlefish from the Western Sahara to The Gambia are considered as non-fully exploited. Stocks are managed poorly in Ghana, Guinea and Guinea Bissau. In all areas, more data are needed about stocks in all areas with greater monitoring, surveillance and enforcement to reduce the risk of Illegal, Unreported, and Unregulated (IUU) fishing. Management recommends that the catch does not exceed current levels and should be reduced where stocks are overexploited. The catch method, hook and line is a very low impact fishing method but large removals of cuttlefish on the ecosystem is a concern.

Biology

Cuttlefish (family Sepiidae) belong to a specialised group of molluscs, known as cephalopods, which also includes octopus and squid. In the North East Atlantic and Mediterranean, the main commercial species is the common cuttlefish (Sepia officinalis), although other species (S. elegans and S. orbignyana) are fished in the Mediterranean. Cuttlefish have eight arms and two tentacles, like squid, but differ from other cephalopods by the presence of a significant internal skeletal/buoyancy structure, the cuttle bone, which is often found washed up on beaches. The common cuttlefish typically has a two year lifecycle, whilst in southern areas one year is normal. After overwintering in deeper waters, cuttlefish move into shallow coastal waters to breed in spring and summer. Females only breed once, and die soon after laying up to 4,000 eggs, which are around 8-10 mm in diameter and known as sea grapesa. They take up to two months to hatch. Males live longer, and breed more than once. Cuttlefish can attain body lengths of up to 45 cm and weigh up to 4 kg, although typically 20-30 cm and 1-2 kg is normal.

Stock information

Stock Area

All Areas

Stock information

In most areas, cuttlefish populations are deemed to be in a good condition. However, the data used to produce stock assessments host much uncertainty. Fishing mortality in most areas (between the Western Sahara and the Gambia) is considered as acceptable at a non-fully exploited level. However, in between Guinea-Bissau and Ghana, either data are too deficient to determine the stock status or the stock is overexploited with fishing mortality estimated as nearly two and a half times that recommended. This is because of large increases in fishing effort. Catches have declined in recent decades, however, recent catch data shows catch increases of 53% (between 2011 - 2012). The average catch is 23,391 tonnes.

Management

Reference points are used to determine the stock status, though data hosts large uncertainties due to unreported catch, misreporting or lack of information on discards. Assessments rely heavily on catch estimates rather than fishery-independent data. This reduces the accuracy of data collected and therefore, reduces the certainty of the stock assessment and therefore, how the fishery should be effectively managed. There is little information available to determine how effective management is at ensuring that the stock is sustainable. In areas were stocks are non-fully exploited, cuttlefish is caught as a bycatch species when targeting octopus and the Commission for the Fishery Committee for Eastern Central Atlantic (CECAF) advise that management should be conducted similarly to that for octopus e.g. through gear selectivity and that catch rates should not increase. In areas where stocks are overexploited or there are insufficient data to determine a stock status, catches should be heavily reduced.

Capture Information

Hook and line fisheries are low impact fisheries: they are very selective and incur minimal bycatch. They have little or no contact with the seafloor and therefore do not require mitigation measures to reduce their impact on habitats. Anchors are often suspended in the mid-water column and therefore do not damage the seabed. Therefore, the main impact that hook and line fisheries present is their impact on the biomass that they remove from the ecosystem.

References

1 - ftp://ftp.fao.org/FI/DOCUMENT/cecaf/Cecaf_SSC7/4E.pdf 2 - ftp://ftp.fao.org/docrep/fao/009/ac479e/AC479E09.pdf 3 - http://www.fao.org/fishery/species/2711/en 4 -http://www.fao.org/docrep/009/y5852e/Y5852E10.htm 5 - ftp://ftp.fao.org/docrep/fao/007/y5852e/Y5852E04.pdf 6 - http://www.fao.org/docrep/003/w4248e/w4248e08.htm 7 - http://www.fao.org/docrep/003/t4890e/t4890e03.htm 8 - http://www.sealifebase.org/summary/Sepia-officinalis.html 9 - http://www.fao.org/docrep/meeting/024/an153e.pdf 10 - http://www.marlin.ac.uk/species/detail/1098 11 - http://www.goodfishguide.org/fish/451/Cuttlefish