The Shark Trust and the British Sub-Aqua Club (BSAC) have announced a new partnership encouraging divers to contribute to research on where sharks and skates lay their eggs.
The collaboration will see BSAC clubs and members support the Shark Trust’s citizen science projects, which help to improve the scientific understanding of species distribution, vulnerability and habitat use, and support the protection of important breeding areas.
Among these initiatives is the Great Eggcase Hunt, in which members of the public are asked to search for ‘mermaid’s purses’ – the eggcases of sharks and skates – and record their findings.
Any diver, snorkeller or beach visitor can submit their survey data, and while beach-based surveys will remain central to the Eggcase Hunt, the Shark Trust says the partnership with BSAC will enable more divers and snorkellers to contribute underwater observations, particularly of eggcases still developing.
Although all information from the survey is valuable, data on in-situ eggcases are somewhat deficient. More than 600,000 eggcases have been recorded through the programme over the past 20 years, but only 0.7 per cent of submissions have come from underwater sightings.
‘Eggcases seen developing underwater are a crucial piece of the puzzle,’ said Cat Gordon, senior conservation officer at the Shark Trust.
‘They help us link the areas where empty eggcases regularly wash ashore with the habitats that are important for this stage of the life cycle.
‘We’re asking divers and snorkellers to keep an eye out for eggcases seen attached to seaweed or seabed habitats.’
She added: ‘Recording these observations will help provide a valuable insight into the critical habitat used for the egg-laying process.’
The partnership will also include promotion of the Great Shark Snapshot, scheduled to take place from 18 to 26 July 2026, during which divers are encouraged to log sightings of sharks, skates and rays.
The initiative aims to build a global dataset of species encounters and encourage year-round reporting via the Shark Trust’s Shark Log Sightings Database.
BSAC will promote both programmes through its Marine Champions network, with clubs encouraged to organise activities and submit data through the Shark Trust’s online recording platform. Results and notable findings will be shared through project updates and an online dashboard.
‘I am delighted that our organisations will be working in partnership to add to the Shark Trust’s impressive data set,’ said Katherine Knight, chair of BSAC’s Environment Committee.
‘This is the perfect opportunity for divers and snorkellers to use their unique perspective on the underwater world to fill an important gap in the data.
‘The impactful work undertaken by the Shark Trust illustrates how they are able to leverage sightings from divers to generate meaningful change for the conservation status of sharks, skates and rays.’
You don’t need to be a BSAC member – or even a diver – to get involved with the Great Eggcase Hunt. Learn more and get involved at www.sharktrust.org/greateggcasehunt.
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