Flapper skate egg nursery site discovery in Scapa Flow

(Image Courtesy of Tritonia Scientific Ltd)

A potential flapper skate (Dipturus intermedius) egg nursery has been discovered in Scapa Flow.

If proven as an egg nursery site, this would be only the second one of its kind found in the world, with the first flapper skate egg nursery site identified at Red Rocks, west coast of Scotland in 2019.

The find in Scapa Flow was made during a detailed seabed habitat survey carried out in May 2025 as part of early planning work for a potential wet storage area.

The survey, commissioned by the Council’s Marine Services team and undertaken by Tritonia Scientific Ltd, revealed a high concentration of flapper skate egg cases in one part of the study area.

Flapper skates are Critically Endangered and are a Priority Marine Feature in Scotland, which is a list of habitats and species of conservation importance given policy protection under the National Marine Plan.

A total of 95 confirmed flapper skate egg cases were identified, with an additional 52 egg cases which are also likely to be flapper skate. The concentration of the eggs confirmed the site as a potentially important egg nursery.

Following this discovery, Baited Remote Underwater Video (BRUV) surveys were conducted by local company Seawise Solutions Ltd to determine the presence of mature adults in the vicinity. Through a limited number of these surveys, it was confirmed that there was one mature male in the vicinity.

In the interests of protecting this incredibly important site, the Council’s Harbour Authority released a Notice to Mariners on the 12th of December 2025, which sets up an exclusion zone which prohibits anchoring, dredging and all diving activities without prior permission from the Harbour Authority.

Dr Jenni Kakkonen, Team Manager for the Marine Environmental Unit at Orkney Islands Council, said: ‘I could not believe it when the Tritonia survey team started reporting the flapper skate egg cases they were seeing during their video survey. This discovery is incredible and such an important piece of the puzzle in understanding flapper skate distribution and presence in Orkney and in Scotland.

“This important discovery, along with the presence of other Priority Marine Features such as maerl beds, seagrass meadows and flame shell beds, among others, demonstrates that it is possible to protect sensitive ecological habitats alongside a busy working harbour when appropriate systems are put into place for their protection.”

Professor John Baxter, has been involved in marine ecological research in Orkney since the 1970’s. He said: “This is a really important discovery that highlights the importance of the marine environment around Orkney for flapper skate and I commend Orkney Harbours proactive action in putting in place the protective measures through the Notice to Mariners which illustrates their commitment to the protection and conservation of the outstanding marine habitats and species around Orkney.”

Daniel Wise, Marine Biologist and Local Diver, Orkney Skate Trust, said: “This discovery is fantastic news for Orkney and for flapper skate. Locally known as barndoor skate, this fish has a long history in Orkney.

“I’ve been involved in community-led survey work on flapper skate in Orkney for nearly 20 years through the Orkney Skate Trust, and finding such a high number of live egg cases really confirms how important Orkney’s waters continue to be for the species.

“The Scapa Flow nursery area may act as an important staging post as flapper skate populations naturally move further south in the North Sea, where they are no longer seen.

“We’re already seeing positive signs, with more skate being recorded locally. This highlights the value of local knowledge and long-term data gathering in supporting responsible, well-informed development and evidence-driven decisions.”

Jane Dodd, NatureScot’s elasmobranch specialist, said: ‘It is really exciting to hear the news of a potential flapper skate egg nursery site in Orkney. This would extend the current known distribution of flapper skate egg nursery areas northwards by about 180km from the Red Rocks egg nursery site off Skye. It is commendable that Orkney Harbours have already set protection measures for the site, safeguarding it from any disturbance and I look forward to working with Orkney Islands Council, so we can discover the extent and potential importance of the site.’ 

Additional information: 

For further information about flapper skates, please visit the Orkney Skate Trust website here: https://www.orkneyskatetrust.co.uk/flapper-skate/ or NatureScots’ here https://www.nature.scot/plants-animals-and-fungi/fish/sea-fish/flapper-skate

If you’re an angler, diver, marine surveyor or just an interested member of the public, Nature Scot has created an app where you can report photographs of flapper skates. This information is vital in tracking skates’ movements, population density and health. You can read more about the project here https://www.nature.scot/app-build-better-picture-endangered-flapper-skates-scotland and download the app here https://play.google.com/store/apps/details?id=uk.ac.sams.skatespotter&hl=en_GB.

It became illegal to commercially land flapper skates in 2009, ensuring any skates caught were released and that any caught by fishing activities as by-catch were returned to the sea.