Seafish species guide - the gurnard

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Research & Development Species guide

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December 2010

Gurnards Gurnards belong to the Triglidae family (1) of fish. There are three common species: red, yellow/tub and grey gurnard. They vary by colour but are very similar in shape and taste. Red gurnard

Red gurnard, Aspitrigla cuculus, is the smallest of the European gurnards. It spawns in summer, can attain a length of 40 cms, a weight of 900g and lives to a maximum of 21. Tub gurnard

Tub gurnard, Chelidonicthys lucerna, is the largest European. It spawns from May to July, can attain a length of 75 cms and lives to a maximum of 15 years. Grey gurnard

Grey gurnard, Eutrigla gurnardus, spawns from April to August, can attain a length of 45 cms and lives to a maximum of six years.

Distribution Red gurnard is widely distributed in the North East Atlantic from southern Norway and north to Mauritania.

Tub gurnard occurs in the Eastern Atlantic from Norway to Senegal, also in South Africa and in the Mediterranean Sea.

Grey gurnard occurs in the Eastern Atlantic from Iceland, in Norway, the southern Baltic and the North Sea to southern Morocco.


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Species Guide – Gurnards. December 2010.

appears to have been an upward trend in the last decade.

Biology Gurnards are able to grunt or growl by using muscles associated with the swim bladder and this is believed to aid in keeping schools together. They feed on benthic crustaceans, other invertebrates and bottom-dwelling fishes.

Fisheries and gears Red gurnard is mainly caught in a mixed fishery by otter trawlers. Tub and grey gurnard are mainly taken as a bycatch in mixed demersal fisheries for flatfish and roundfish. However the market for gurnard is limited and they are often thrown back into the sea as an unwanted bycatch and subsequently discarded. Surveys indicate that this species is one of the most widely discarded (3).

Stock assessment and catches There are no formal assessments or advice on gurnards However, there are a number of sources of information on these species and their role in the ecosystem (4,5,6).

Tub gurnard – As for red gurnard, French trawl fisheries and research vessel data provide the best time series for this species. Information is available for the Bay of Biscay, Celtic Sea, Western Approaches, English Channel and North Sea. Most of these results indicate fluctuation in abundance without trend with some evidence of increasing numbers of tub gurnard overwintering in the North Sea in recent years. This effect has been observed with other species such as red mullet which until recently did not overwinter in the North Sea. Grey gurnard – Due to their low commercial value there is widespread discarding of this species so only research vessel data can be considered a valid source of information. The research vessel surveys in the North Sea show a marked increase in abundance over the period 1987-2009, and relatively stable, though fluctuating abundance in the Skagerrak and Kattegat.

Ecological aspects

According to landings statistics the annual catches in the North East Atlantic from 20062009 have been (2):

Gurnards are key predators in the North Sea and their importance is considered to have increased over recent years (4).

Tonnes

Sustainability

Red Tub Grey

2006 5171 2995 529

2007 5175 3416 399

2008 4778 2510 317

2009 4055 3058 438

There are uncertainties in landings data and some nations do not discriminate between the species in the landings data. Red gurnard – French fishing vessels land the most red gurnard and it is data from these and research vessels which provide the best time series for this species. Information is available for the Bay of Biscay, Celtic Sea, Western Approaches, English Channel and North Sea. Most of these time series indicate fluctuations in abundance without trends, with the exception of the North Sea where there

Taken together the information described above suggests that gurnard populations are relatively robust; that is current exploitation is not likely to seriously affect their abundance.


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Species Guide – Gurnards. December 2010.

Responsible Sourcing Services This guide is one of a series of Seafish Responsible Sourcing Guides. See: http://www.seafish.org/b2b/rss

Product Characteristics Gurnards are very distinctive bottom-living fish with large heads and eyes. The head is protected by large bony plates and strong spines. The lower three rays of the pectoral fins are separate, finger-like processes that contain sensory organs. Red gurnards are bright red with pinkishsilver mottling on the sides and head. The protective bony plates on the head which are characteristic of all gurnards are very conspicuous in this species. Along the lateral line there is a row of large, plate-like scales. Tub gurnards can vary in colour from bright red with pinkish mottling to yellowish-brown with darker brown or green mottling. The pectoral fins have brilliant peacock blue spots and outer rim. The grey gurnard is a relatively slender bodied gurnard with a sharply pointed snout. The colour ranges from grey to greyish-brown with small whitish-cream spots and there is a characteristic dark blotch on the rear edge of the first dorsal fin. Gurnards are most commonly used in fish stocks, soups or Mediterranean fish stews. It may be marketed fresh or frozen and eaten pan-fried, broiled, micro-waved or baked. The Gurnard is a tricky fish to fillet and ‘debone’, but has been gaining in popularity. The red gurnard was the winner of the Billingsgate School Sustainable Seafood Award 2008 (7) and has been increasingly

endorsed by celebrity chefs. There is a recipe for red gurnard in Rick Stein’s Mediterranean Escapes (BBC Books, 2007). The River Cottage Fish Book by Hugh FearnleyWhittingstall and Nick Fisher (Bloomsbury, 2007) includes red gurnard recipes for ‘Potroasted gurnard’, as a whole white fish in ‘Crustacean soup’ and a descaled and gutted red gurnard for cooking as ‘Deep-fried whole fish with citrus salsa’.

Supply chain standards Seafish has developed supply chain standards from capture to retailer: • Responsible Fishing Scheme. Sets best practice standards for fishing vessels: (BSi: PAS 72:2006). • British Retail Consortium (BRC) Global Standard/Safe and Local Supplier Approval (SALSA) certification. Designed to raise standards in the seafood processing and wholesaling sectors.

References and sources 1.www.food.gov.uk/foodindustry/guidancenotes/la belregsguidance/fishlabellingregs2010eng 2. www.ices.dk/fish/CATChSTATISTICS.asp

3. Enever R et al 2007 Fisheries Research 86 (2007) 143–152. 4. Mackinson S and G. Daskalov (2007) Sci. Ser. Tech Rep., Cefas Lowestoft, 142: 196pp 5.www.ices.dk/reports/ACOM/2007/WGNEW/WG NEW07.pdf 6.www.ices.dk/reports/ACOM/2010/WGNEW/WG NEW%202010%20.pdf 7.www.seafoodtraining.org/6_mike_berhtet_m&j_ seafood_27.02.08.pdf

Contact: Bill Lart - Tel: 01472 252323 Email: w_lart@seafish.co.uk Karen Green - Email: k_green@seafish.co.uk 18 Logie Mill, Logie Green Road, Edinburgh EH7 4HS t: 0131 558 3331 f: 0131 558 1442 e: seafish@seafish.co.uk w: www.seafish.org SIN: http://sin.seafish.org supporting the seafood industry for a sustainable, profitable future


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