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Winter 2023/24 Ratings Updates - inc. a NEW tuna fishery

Posted on: 29th May 2024

Winter 2023/24 Ratings Updates - inc. a NEW tuna fishery

Every winter, we review half of the sustainability ratings for our Cornish species (the other half is done in Summer - see these changes here). Our winter ratings changes, based on the most recent available scientific advice and management information, are now complete and are live on our website.

There have been some significant changes in this review... Including:

  • NEW Line-caught Cornish tuna
  • Undulate Ray
  • Red Mullet
  • Crawfish

Read below for details...

We will soon be launching our new Gold Standard for businesses making extra commitments to serve as much sustainable seafood as possible!

If you or anyone you know might be a good candidate then please get in touch so we can make sure your business gets the credit it deserves.

In the coming months, keep your eyes peeled for this shiny new logo, and on our social media accounts to find our most sustainable seafood businesses in Cornwall.
NEW line caught Atlantic Bluefin Tuna fishery to be recommended
An Atlantic Bluefin Tuna jumping after its food in Cornish waters.
The major change in this update is the addition of a new rating for line-caught Atlantic bluefin tuna.

Following the opening of a targeted line fishery in August 2023, this new rating comes straight onto the recommended list. After an absence in the UK of over 60 years, and despite facing stock collapse in the early 2000s, eastern Atlantic Bluefin Tuna stocks have recovered, and fortunately these amazing animals have returned to our waters after being sighted again for the first time in 2014. We are lucky to have these powerful, intelligent fish back in UK waters, and must ensure that Atlantic bluefin tuna is not overfished once again.

We don't yet know the full reasons behind their return, however emergency management measures put in place from 2007-2016 have helped to save the species from the brink of stock collapse. In 2021, Atlantic bluefin tuna moved from Endangered, to Near Threatened on the IUCN Red List. The UK was then allocated quota for Atlantic bluefin tuna for unavoidable bycatch in ring-net, gill-net, and trawl fisheries. This year, 39 tonnes of a total 65 tonnes was allocated to a brand new, trial, targeted, hook and line fishery.

The fishery is highly regulated, 2023 saw only 10 fishing licenses, increasing to 13 in 2024, given out across the country, and licenses to trade line-caught Atlantic bluefin tuna a requirement for merchants. While too early to know it's effectiveness, the size of the fishery, and the measures in place mean there should be good traceability of the line-caught fish throughout the supply chain and sets the bar for other fisheries to follow suit.

The Atlantic bluefin tuna stock score improved last year, but it is the strict management and low impact of this line fishery that has earned its place on the recommended list. We still have concerns for management of the wider fishery, both in the UK bycatch fishery and the wider eastern Atlantic, and there is uncertainty in both stock mixing and recruitment so we will be monitoring this fishery closely.
Pot-caught and diver collected crawfish ratings to improve from a 5 to a 4.

This vulnerable, previously overfished species is now seemingly doing better in our waters; fishers are now regularly catching large amounts of crawfish and we no longer have concern for biomass. This means an improved stock score from 1 to 0.75. We do, however, still have serious concerns for fishing pressure, particularly with gillnets. We need better data on the stock status for crawfish in Cornish waters.

Management has also improved from 1 to 0.75 after the offshore MLS was harmonised with the inshore measure of 110mm, and a closed season, from February to April will be in effect for 2024. Management is still insufficient, and the industry is calling for further effort restrictions urgently.

The higher capture method score for gillnets (due to poor selectivity) prevents this rating improving.

It's really encouraging to see the fishing industry asking for better management of their fishery. There must be further management to see crawfish before crawfish can be added to our recommended list.
Two (look closely) crawfish on a wreck. Credit: Matt Slater
Red mullet a fish to avoid

Red mullet in Cornish waters is extremely data poor, and TACs have frequently exceeded ICES advice in recent years. Concern for fishing pressure, largely international, and biomass puts the stock score at a 1, and moves all ratings for red mullet to 5 - fish to avoid
MSC certified Cornish sardine, pilchard, remains rated a 2.

Sardine in the southern Celtic Seas and English Channel is abundant and there is no concern for fishing pressure. Biomass in 2023 was 456,482t – the highest since the time series began in 2017, and well above the trigger point. Therefore, there is no concern for the biomass of this stock. The Cornish Sardine Management Association (CSMA) requested an increased catch of 11,150t for 2023 and Cefas advised that this rate of harvest would be precautionary and would not lead to overexploitation of the stock.

As a result, we have no concern for biomass or fishing pressure, and the sardine stock score remains at 0.25 - with an overall MSC ring net rating of 2. Always buy MSC certified sardines.
Mevagissey ring-netter, Chris Blamey, and his crew fishing for pilchards. Credit: Matt Slater
Changes for sharks, skates, and rays

Undulate ray, following a total ban, and then a very gradual increase in quota, is doing very well in the English Channel. A proactive management decision to keep catch limits the same despite a good stock assessment means Undulate Ray jumps straight from a 5 onto our recommended list. This is an excellent example of how precautionary management can help species recover.

As always, we advise caution when buying skates and rays, once skinned, it is impossible to tell which species it is, so make sure to ask the seller what species, where, and how it was caught. If in doubt, don't buy it.

Stocks of nursehound, and smoothhound have improved, with better, but still limited, data. This means both will now be rated a 4.

Elasmobranchs are slow-growing and many species not doing so well cannot afford increased fishing pressure.

Thankyou for your support,
Matt Slater, Oscar Miller and Ruth Williams

Cornwall Good Seafood Guide
Cornwall Wildlife Trust
Five Acres, 
Allet, Truro

Thanks to all of our supporters! 

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Our vision:
Healthy seas supporting healthy wildlife and sustainable fisheries. 


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