Intriguing photos taken at Scotland's Bass Rock depict the eye coloration of seabirds who have survived the avian flu.
First discovered on the island in the Firth of Forth in June 2022, northern gannets have black eyes instead of the typical pale blue.
According to blood test results released last month, the birds had previously managed to survive the infection.
Photographs by Rebecca James were taken this month during a trip to Bass Rock.
Finding out what causes the gannet's eyes to turn black would require ophthalmology tests on the bird.
The largest Northern gannet colony in the world can be found on Bass Rock, which is northeast of North Berwick.
The birds come to Scotland to breed during their annual migration from west Africa, but avian flu has severely reduced their numbers in recent years.
Ms. James captured her images during a eagerly anticipated boat trip to Bass Rock to view the gannets.
She said: "Following four failed attempts, it was fifth time lucky and I was able to climb up Bass Rock to take pictures of the passing gannets. .
"Those who survived last year's avian flu outbreak are displaying changes in their eye color.
"I took a picture of a breeding pair greeting each other after coming back from the sea, one of them had the black and blue eye combination. ".
Researchers from the Scottish Seabird Centre, the Animal Plant Health Agency, the Universities of Glasgow, Edinburgh, and Heriot Watt, as well as the RSPB Scotland, examined the eye coloration and overall health of the gannets.
At its busiest during the breeding season, Bass Rock can support up to 150,000 fish.
According to the team's research, avian flu caused adult bird survival to be 42 percent lower between 2021 and 2022 than it had been over the previous 10-year average.
