8ft ambush shark 'more common' than thought on Welsh coast
An enigmatic species of shark known to be favour Welsh waters could be more abundant than previous suspected, scientists believe. The Angel shark, a large flat species resembling a stingray, is unique because it has evolved very differently to other types of shark.
Previously only reliably spotted around the Canary Islands, catch evidence from Welsh fishermen has shown that Cardigan Bay is also a stronghold for this elusive and vulnerable species.
The Welsh population had thought to be shrinking dramatically as a result of habitat damage and bycatch fishing, with one study indicating a 70% decline since 1970. A major conservation project was launched in the hope of saving a species that lingers on the sea floor, half-buried in sand and mud, waiting for prey to swim near them. They can grow up to 2.4m (8ft) long.
However a new study, 'People & Nature', from the Zoological Society of London (ZSL) and Natural Resources Wales (NRW) suggests previous Angel shark counts were wide of the mark. Its authors believes changes to commercial fishing practices have seen fewer angel sharks caught.
As the speckled, caramel-coloured sharks are masters of camouflage, finding them on the sea floor is virtually impossible. Instead, evidence from boat captains is the only reliable way the population can be assessed. It's now thought fishermen are catching fewer not because numbers are dwindling but because they are targeting different waters and using species-specific nets.
To reach its conclusions, the ZSL-led study harnessed the expertise of Welsh fishing organisations. Co-author was Charlie Bartlett, a charter fisherman from Gwynedd, who said: 'I've spent over 50 years working along the Welsh coast, and over the years I've come to know these waters inside out.
'With their large, flat fins, Angel sharks are unlike any other shark we see here - and over the years I've been fortunate to encounter the species a number of times.' Join the North Wales Live Whatsapp community now
(Image: Charlie Barlett)
In the 40 years to 2020, some 1,642 Angel sharks were reported in Welsh coastal waters. A particular safe haven is in an area south of the Llŷn Peninsula. While they pose very little risk to humans, they have been known to bite when provoked.
Literature analysis going back two centuries revealed they have a long maritime heritage in Wales. No fewer than 16 different names were uncovered, including Monkfish, Banjofish, Bafoon, Shovelnose and Devilfish.
Its traditional Welsh name is Maelgi (Monkfish). The species has been adopted as the flagship species for marine conservation in Wales.
Working with the Welsh Fishermen's Association (Cymdeithas Pysgotwyr) and Angling Cymru Sea Anglers, scientists interviewed 27 fishers about their operations between 1968 and 2019. It became clear modern practices involve fewer interactions with Angel sharks, leading to fewer sightings.
(Image: Jake Davies/JD Scuba/Project SIARC)
Lead author Francesca Mason, a ZSL researcher at the Institute of Zoology's Ocean Predator Lab, said: 'There may be more Angel sharks swimming off the Welsh coast than we previously thought – we're just having a harder time spotting them.
'While this is a good sign if less Angel sharks are being caught accidentally, it also means we now need new ways to monitor them to build a more accurate picture of how these sharks are doing.'
Instead of relying on chance sightings, scientists are now pinning their hopes on a novel technique involving environmental DNA (eDNA). This can build up in the shark's surroundings through the shedding of dead skin cells or blood loss from a wound.
Already eDNA is being measured for Angel Shark Project: Wales, part of the wider work of Project SIARC (Sharks Inspiring Action and Research with Communities).
(Image: Jake Davies/JD Scuba/Project SIARC)
Jake Davies, technical specialist for Project SIARC, said: 'With their excellent camouflage, one of the hardest challenges we face studying Angel sharks is simply finding them. eDNA allows us to study species without having to spot them.
'By studying eDNA in Cardigan and Carmarthen Bays, we've confirmed the presence of a range of native sharks, skates and rays - including Angel sharks - in these more turbulent waters where other monitoring methods aren't as effective.
'Fishers today may be less likely to come across Angel sharks than they were 50 years ago, but through combining this technique with local knowledge, we can continue building a stronger picture of their status and distribution along the Welsh coast.'
The Angel shark work was supported by the On the Edge conservation charity, the National Lottery Heritage Fund, Welsh Government and the Welsh Government's Nature Networks Fund. Sign up for the North Wales Live newsletter sent twice daily to your inbox
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