Avian flu devastating Wales' seabirds, says RSPB

The number of Sandwich terns on Anglesey roughly halved in a year

Bird flu is having a devastating impact on the seabird population around Wales, the RSPB has warned.

In some species the charity said bird flu had "completely reversed" previously positive trends.

The number of gannet nests at Grasshom in Pembrokeshire - the main colony in Wales and once the fourth largest in the world - dropped from 34,491 in 2022, to 16,482 last year.

The Welsh government said it was committed to delivering a seabird conservation strategy this year, aiming to protect species from avian flu and other emergencies.

For the first time, a new report tries to quantify the impact of Highly Pathogenic Avian Influenza (HPAI) on UK seabirds.

The report said gannets, common terns and Sandwich terns were among 11 species that were increasing in numbers in Wales before the first major outbreak of HPAI in 2021.

Julian Hughes, head of species for RSPB Cymru, said: "The latest figures say Grassholm is now back to where it was in 1969.

"In one year, HPAI has undone what took more than 50 years of growth."

Nearly all of the Sandwich terns in Wales nest at Cemlyn on Anglesey and figures from North Wales Wildlife Trust showed there were between 2,200 and 2,400 nests there in 2022.

Last year, there were 1,100.

Overall, the number of common terns and Sandwich terns in Wales has dropped by more than 40%, according to the RSPB.

Black-headed gulls, - which were red-listed before bird flu - have seen a decrease in population in Wales of 77% since the last detailed census in 2015-21.

Other species, including kittiwakes and herring gulls, were already declining because of other threats faced by sea birds, such as climate change, and continue to do so, the charity said.

Mr Hughes said: "In 2022-23 some of our biggest colonies were devastated by avian flu and we saw many dead adults and chicks.

"Sea birds live for a long time but produce only one or two chicks per year, so bird flu will have an impact on their population for several, or many, years to come."

There are currently no reported cases of HPAI in wild birds in Wales, but migrating sea birds are due to return later this year.

The Welsh government said its sea bird conservation strategy, being done in conjunction with the Joint Nature Conservation Committee, Natural Resources Wales, British Trust for Ornithology and RSPB was "making good progress".

It added: "It will identify opportunities to enhance our seabird populations’ resilience to pressures such as avian flu, as well as the climate and nature emergencies."