Recently discovered Sandwich Tern colony is thriving

A newly discovered breeding colony of Sandwich Tern in North Wales is thriving, say conservationists.

The colony, on a small inaccessible island at the Inland Sea, Anglesey, was only found in 2022 by local birder Mark Sutton. He promptly contacted RSPB Cymru and triggered efforts to monitor and protect the site. The island, owned by the Welsh Government, was purchased when the A55 was built across Anglesey in the hope that it might one day become a significant nesting site for terns.

A partnership between RSPB Cymru, the North and Mid Wales Trunk Roads Agent and Welsh Government on Anglesey has since helped protect the colony, with a seasonal warden employed and electric fencing and vegetation management work funded.

Sandwich Tern is a localised breeding bird in Wales (David Rowlands).

The numbers of terns that bred on the island was even higher than originally hoped. Surveys carried out by the warden showed that 118 pairs of Sandwich Terns settled to breed, rearing at least 71 young. The island also provided a home to 157 breeding pairs of Black-headed Gulls, which successfully reared more than 100 young. 

There were also approximately 40 pairs of Common and Arctic Terns found breeding on the small islets near to the main island. The Inland Sea sits within the Anglesey Terns Special Protection Area (SPA) a site of European importance for terns which includes the larger tern colonies at The Skerries and Cemlyn Lagoon.  

RSPB Cymru Warden, Ian Sims, said: "Although touched by avian flu, the colony luckily escaped the worst ravages of this disease which has caused so much havoc in seabird colonies in the UK this year and last, making it all the more important in these uncertain times.

"It may be the junior partner at the moment, but it adds to the resilience of tern populations within the SPA; and also has fantastic potential to grow, and with some luck and some care that is exactly what we hope to see it do in the coming years."