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Spurdog, Spiny Dogfish, Dogfish, Rock Salmon or Flake

Squalus acanthias

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
Accreditation -
Fish type - White round fish

Sustainability rating Click for explaination of rating

This fish, caught by the methods and in the area listed above, is the least sustainable fish to eat and should be avoided. Click on the rating icon above to read more and on the alternatives tab below to find sustainable fish to eat.


Sustainability overview

Spurdog is a long-lived, slow-growing, and late-maturing species and therefore particularly vulnerable to fishing mortality. The North East Atlantic stock is now considered to be depleted. Targeted fisheries for the species have effectively been outlawed as there is Zero TAC for the species in 2015 and 2016. Bycatch in non-target fisheries is still thought to be a problem and must be minimised to allow the stock to rebuild. The species is assessed as Critically Endangered in the North East Atlantic by IUCN and has been recently added to the OSPAR list of threatened and/or declining species and habitats.

Biology

Spurdog (spiny dogfish, dogfish, rock salmon or flake) are sharks. In the North Atlantic female dogfish grow to a maximum total length of 110-124cm, males 83-100cm. In the Northwest Atlantic spurdog mature at around 60cms total length and at an age of 6 years for males and at around 75cms, at an age of 12 years for females. In the Northeast Atlantic females are reported to mature slightly larger and older at 83cm 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. The fecundity of spurdog increases with length, and females of 100-120cm produce a higher number of pups (10-21) than those females below this length. Spurdog forms size and sex specific schools.

Stock information

Stock area
All Areas (Barents sea to Portuguese Coast)

View map areas

Stock information
ICES tagging information indicates that there is one stock in the northeast Atlantic, distributed from the north of the Bay of Biscay to the Barents Sea. The stock suffered a high fishing mortality for more than four decades, and was not managed during this time. The spawning biomass and recruitment have declined substantially since the 1960s to the lowest observed. SSB and recruitment are now showing slight increases from these historical lows. Fishing mortality has declined substantially and is estimated to be well below the MSY level. Given that spurdog spawning biomass and recruitment are currently the lowest observed and that spurdog is a long-lived, slow-growing, and late-maturing species and therefore particularly vulnerable to fishing mortality,ICES advises on the basis of the MSY and precautionary approach that there should be no target fishery in 2015 and that bycatch in mixed fisheries should be reduced to the lowest possible level and a rebuilding plan developed for this stock. This species is assessed as Vulnerable (2006) globally and as Critically Endangered in the North East Atlantic by IUCN - The International Union for Conservation of Nature or The World Conservation Union www.iucn.org and and has been recently added to the OSPAR list of threatened and/or declining species and habitats based on evidence of decline and threats throughout the OSPAR maritime area.

Management

The stock suffered a 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 but it is not known at what levels. ICES recommends the introduction of a maximum landing length (MLL), starting at 100cm, to protect the mature female spurdog in this long lived species. 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.

Capture information

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.

Read more about capture methods

Alternatives

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.

Alaska pollock, Walleye pollock Depending on how and where it's caught this species ranges from sustainable to unsustainable. Click the name to display only the sustainable options.

Basa, Tra, Catfish or Vietnamese River Cobbler Depending on how and where it's caught this species ranges from sustainable to unsustainable. Click the name to display only the sustainable options.

Bass, seabass Depending on how and where it's caught this species ranges from sustainable to unsustainable. Click the name to display only the sustainable options.

Bream, Gilthead Depending on how and where it's caught this species ranges from sustainable to unsustainable. Click the name to display only the sustainable options.

Cod, Atlantic Cod Depending on how and where it's caught this species ranges from sustainable to unsustainable. Click the name to display only the sustainable options.

Coley, Saithe Depending on how and where it's caught this species ranges from sustainable to unsustainable. Click the name to display only the sustainable options.

Haddock Depending on how and where it's caught this species ranges from sustainable to unsustainable. Click the name to display only the sustainable options.

Hake, Cape

Japanese amberjack, Yellowtail or Seriola

Meagre

Pouting or Bib

Sturgeon Depending on how and where it's caught this species ranges from sustainable to unsustainable. Click the name to display only the sustainable options.

Tilapia

Whiting Depending on how and where it's caught this species ranges from sustainable to unsustainable. Click the name to display only the sustainable options.


References
ICES Advice 2014, Book 9 http://www.ices.dk/sites/pub/Publication%20Reports/Advice/2014/2014/dgs-nea.pdf; ICES 2011. Report of the Working Group on Elasmobranch Fishes, ICES HQ, 20-24 June 2011. ICES CM 2011/ACOM:19; Shark Trust 2010. An illustrated Compendium of Sharks, Skates, Rays and Chimaera. Chapter 1: The British Isles and Northeast Atlantic. Part 2: Sharks

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