National Trust says bird flu affecting sea bird colonies on Welsh coast
Cemlyn on Anglesey and the Pembrokeshire coast have been noted by the charity.
The National Trust says as many as 7 thousand of seabirds have died from bird flu at colonies across the UK this year.
Cemlyn on Anglesey and the Pembrokeshire coast are among the areas noted by the charity which has described the numbers as 'extremely worrying'.
A decline in sea birds at Long Nanny, on the Northumberland coast, Brownsea off the south coast of Dorset as well as parts of the east and north coasts of Northern Ireland have also been noted.
At Cemlyn in Wales, more than 1,200 dead birds were collected, 771 of which were Sandwich Terns.
Chris Wynne, senior reserves manager for the North Wales Wildlife Trust said: "Last year our seabirds escaped bird flu, so it has been really distressing to see its impact here, over the past few months."
The Pembrokeshire coast was also affected with hundreds of dead wild birds washing up on beaches.
UK chief vet Christine Middlemiss said: "We recognise that the current outbreak of highly pathogenic avian influenza poses a significant threat to the UK's wild bird populations and share the concerns about the impact on breeding populations, particularly seabirds that nest closely in large numbers.
"Dealing with disease in wild mammals that are frequently on the move is extremely difficult globally but we have been working very closely with partners on this issue since the impacts on wild birds started to become apparent and we keep the outbreak in these populations under close review."