Following the discovery of numerous dead birds, bird flu testing was conducted at a nature reserve in Aberdeenshire.
At Forvie National Nature Reserve, more than 200 dead sandwich terns and a number of dead black-headed gulls were discovered, according to environmental agency NatureScot.
The organization claimed samples had been taken for testing, and the outcomes would determine whether it is avian flu.
Human health is not at high risk from viruses.
NatureScot reported that some seabird species had returned to Scotland in noticeably fewer numbers after an avian flu outbreak last year.
Shetland's great skuas seemed to have been hit particularly hard.
The organization declared: "We are concerned about the unprecedented avian flu outbreak over the past two years, and we continue to work with partners through the Scottish Task Force to ensure that we have the best monitoring and guidance for land managers in place.
People should not handle sick or dead wild animals, and we advise people visiting coastal areas to keep their dogs on leashes to prevent them from picking up dead animals.