Good Fish Guide
Spurdog, Spiny Dogfish, Dogfish, Rock Salmon or Flake
Method of production - Caught at sea
Capture method - Demersal otter trawl
Capture area - North East Atlantic (FAO 27)
Stock area - All Areas (Barents sea to Portuguese Coast)
Stock detail - I-IX
Fish type - White round fish
Avoid buying spurdog. Spurdog is a long-lived, slow-growing, and late-maturing species and therefore particularly vulnerable to fishing mortality. The North East Atlantic stock is critically endangered and listed by OSPAR as a threatened and/or declining species. Targeted fisheries for the species have effectively been outlawed as there is Zero TAC for the species in 2017 and 2018. Bycatch and discarding in non-target fisheries is still thought to be a problem and must be minimised to allow the stock to rebuild. Recent research has focused on designing a risk-based traffic light system to avoid their capture and a responsible handling code of conduct to increase survivability when discarded.
Spurdog (spiny dogfish, dogfish, rock salmon or flake) are sharks. In the North Atlantic female dogfish grow to a maximum total length of 110-124 cm, males 83-100 cm. In the Northwest Atlantic spurdog mature at around 60 cms total length and at an age of 6 years for males and at around 75 cms, at an age of 12 years for females. In the Northeast Atlantic females are reported to mature slightly larger and older at 83 cm total length and 15 years. Gestation or pregnancy lasts between 18 and 22 months, one of the longest recorded for any vertebrate, and they give birth to live young called 'pups'. The fecundity of spurdog increases with length, and females of 100-120 cm produce a higher number of pups (10-21) than those females below this length. Spurdog forms size and sex-specific schools.
All Areas (Barents sea to Portuguese Coast)
The spawning biomass and recruitment for Northeast Atlantic spurdog has declined substantially since the 1960s to the lowest level observed, but appear to have stabilized over the last decade. The harvest rate has declined substantially and is estimated to be well below the MSY level.ICES advises that when the precautionary approach is applied, there should be no targeted fisheries on this stock in 2017 and 2018.
The stock suffered high fishing mortality for more than four decades, and was not managed during this time. There is no management plan for this stock in the ICES area. The total allowable catch (TAC) for this species is currently set at zero, there have been no target fisheries in EC or Norwegian waters since 2011. Discarding takes place and appears to have increased since the TAC was reduced to zero. Additionally, their significant drop in discards has led to an increased level of retained smooth-hound sharks. ICES recommends the introduction of a maximum landing length (MLL), starting at 100cm, to protect the mature female spurdog. It is thought this would have strong benefits for the stock and it is hoped that such an MLL would deter fisheries from targeting areas where large females occur. Norway has had a MLL of 70cm since 1964. Recent research has been conducted to improve spurdog management in UK waters: this includes allowing a small (2 tonne) bycatch allowance for research to make a bycatch reporting tool. Additionally, code of conducts and selectivity trials have been conducted which may soon be incorporated into management.
Historically, spurdogs were subjected to large targeted fisheries but were also taken as bycatch in mixed trawl fisheries. Spurdogs form size- and sex-specific shoals and therefore aggregations of large fish (i.e. mature females) are easily targeted by longline and gillnet fisheries. All target fisheries in EU waters (including for the UK fleet) have ceased - as a zero TAC is in place for EU vessels and is now largely taken as bycatch in mixed demersal trawl fisheries. The survival rate of spurdog released from longline fisheries is high, but is lower in gillnet and trawl fisheries. Norway has a 70cm maximum landing size but it is not known if this is effective at reducing exploitation of mature females. A tool allowing fishing vessels to report spurdog by-catch in (near) real time, was successfully trialed under Shark By-Watch in the Celtic Sea. A selectivity grid was identified as a potential, viable gear modification to reduce spurdog bycatch in towed commercial fishing gear. For the demersal longline fishery, attraction devices such as electric decoys were considered a potential option. A recent project has focused on combating these issues: fishers, policy-makers, scientists and NGOs have been assessing ways to reduce spurdog fishing mortality by using a tool: a real-time, self-reporting spurdog by-catch avoidance scheme. This aims to help the industry avoid spurdog by-catch hotspots. Another tool was using a gear modifications in trawling gear and electric pingers to deter spurdogs. Additionally, the Shark Trust have designed a code of conduct to ensure responsible handling of spurdog for optimum survival rates.
Based on method of production, fish type, and consumer rating: only fish rated 2 and below are included as an alternative in the list below . Click on a name to show the sustainable options available.
ICES Advice 2016, Book 9 http://www.ices.dk/sites/pub/Publication%20Reports/Advice/2016/2016/dgs-nea.pdf;
ICES Advice 2014, Book 9 http://www.ices.dk/sites/pub/Publication%20Reports/Advice/2016/2016/dgs-nea.pdf;
Shark Trust 2010. An illustrated Compendium of Sharks, Skates, Rays and Chimaera. Chapter 1: The British Isles and Northeast Atlantic. Part 2: Sharks ; E. Hunter, S. Hetherington, E.J. Ross, J. Scutt Phillips, R. Nicholson, K. Borrow, L.E Rutland, D. Donnan, J. Wiggins, D. Righton & V. Bendall. 2016.
Shark By-Watch UK 2 Understanding by-catch of elasmobranchs in UK waters: A nationwide programme, a regional approach.;
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