Scilly seabird survey finds worrying declines

The Isles of Scilly Wildlife Trust (IOSWT) and RSPB have issued a call for action following worrying results from the latest seabird survey across the archipelago.

The 2023 survey found overall declines of some 20% during the eight years since the previous study, with the bigger picture showing a loss of nearly half of the islands' seabirds over the least three decades. 

Common Tern has been lost as an annual breeder, with Kittiwake expected to follow. Steep declines have also been noted among the gull populations since 2015, including a dramatic 58% drop in Great Black-backed Gull.

Kittiwake is expected to be lost as a breeding bird in Scilly (Rebecca Nason).

Although the study confirms that the islands still hold one of the most significant seabird colonies in England, it reflects a pattern of decline over 30 years, and fewer than 7,000 breeding pairs of seabirds remain across the islands.

In positive news, where action has been taken to restore island habitats – for example successful, the removal of rats on St Agnes and Gugh – burrow-nesting seabirds have experienced a remarkable recovery. European Storm Petrels and Manx Shearwaters have seen significant increases, with the latter species doubling in number during the last eight years.

Responding to the report, Dr Vickie Heaney, Isles of Scilly Wildlife Trust (IoSWT) Seabird Ecologist, said: "The wealth of data provided by such a comprehensive survey means we can be confident in our assessment that our seabirds are under threat. 

"The evidence of storm petrel and Manx Shearwater success on St Agnes and Gugh and our rat-free islands like Annet is clear – rat removal works. The 2023 results are a call-to-action for collective future island restoration projects if we are to fulfil our vital role as a place of safe breeding for our seabirds and meet the challenges our wildlife faces."

Paul St Pierre, Conservation Officer at the RSPB, added: "The Isles of Scilly is a very special place for seabirds and this latest survey adds to long term information highlighting their differing fortunes. Establishing a funded biosecurity plan for all the islands will make the islands a safer place for seabirds to breed and improve their resilience in the face of increasing climate challenges.

"Landscape Recovery Scheme funding is one of the few opportunities that could support a collaboration between organisations, local communities and businesses to secure the future of the islands' seabirds in this way and help the delivery of key government objectives for wildlife."

The 2023 survey was carried out in partnership between IOSWT and the RSPB. It was principally funded by Natural England and the Isles of Scilly AONB Partnership, with match-funding being provided by the Isles of Scilly Wildlife Trust and the RSPB.