Dozens of wild birds have died in a suspected avian flu outbreak at a national nature reserve.
Consultant ornithologist Peter Stronach found 160 individual birds of 20 species at Loch Fleet, near Golspie in Sutherland.
Mr Stronach said he believed a virus was the likely cause due to the large number of dead birds.
The Scottish government said the recent winter had seen the largest outbreak of avian flu in the UK to date.
It said more than 100 commercial and garden poultry flocks were affected.
In Scotland, there were cases reported in Dumfries and Galloway, Aberdeenshire and Ayrshire.
- Bird flu outbreak at wildlife rescue centre
- Flock of poultry tests positive for bird flu
- Avian flu outbreak surveillance zones lifted
Mr Stronach came across the birds on a walk earlier this week.
He initially counted 72, before returning to make a complete circuit of the coastal reserve and found more dead birds.
They included pink footed geese, shelducks, carrion crows and fulmars.
He said: "To see that number of birds is very, very unusual."
Mr Stronach said avian flu viruses were known to carried by pink footed geese. He also said the behaviour of surviving birds he spotted also pointed to it being flu.
He said: "The eiders I had seen still alive were flying around in circles and being dizzy, which are symptoms that have been seen in other species."
The Scottish government said public health advice was that the risk to the general public from bird flu was "very low".
A spokesman said: "However, the risk to people with intensive exposure to infected birds is considered to be low.
"Food standards bodies advise that avian influenzas pose a very low food safety risk for UK consumers, and it does not affect the consumption of poultry products including eggs."
Avian flu viruses can spread naturally among some wild birds, such as geese, and can infect domestic poultry and other bird and animal species.
The government said any discovery of five or more dead wild birds should be reported to the Department for Environment, Food and Rural Affairs (Defra).