Mystery surrounds the death of several seabirds that have washed up in Broughty Ferry.
Dead birds have been spotted on the shoreline in Dundee and other locations on the east coast of Scotland in recent weeks.
Charity RSPB Scotland estimates that the number of deaths is in the high hundreds.
However, the fatalities are not being linked to bird flu.
Cause of seabird deaths in Broughty Ferry ‘unclear’
More than a dozen dead birds were spotted near Broughty Castle on Wednesday.
A spokesperson for RSPB Scotland told The Courier: “Seabirds have been dying and washing ashore across the east coast of Scotland over recent weeks.
“The main species affected to date is the guillemot, and the numbers exceed the high hundreds, with a high proportion being adult birds.
“The cause remains unclear.
“Numerous beached birds have been tested for highly pathogenic bird flu, which has killed many thousands of wild birds in Scotland over the past three years – but all have tested negative so far.
“Seabird die-offs like this are not unprecedented but have been more frequent than normal recently, and are a cause for real concern.”
The charity says breeding seabird numbers in Scotland fell by nearly half between 1986 and 2019 – before the impact of bird flu took hold.
Climate change, leading to food shortages and toxic algae, is a possible cause.
The RSPB says ending sandeel fishing, restoring and protecting breeding sites, and monitoring fishery bycatch effectively, could help but will require “political will”.
The Courier reported earlier this year how hundreds of dead birds had washed up at Lunan Bay in Angus amid fears of a bird flu outbreak.