Bird flu has been confirmed in a pair of sick knots that were found in the north-east.
The animals were brought to New Arc in Ellon in December but died shortly after arriving.
The rescue centre contacted the authorities as they were suspicious about the birds.
They confirmed that both knots were suffering from avian flu.
In an online statement, New Arc urged people to be careful when picking up ill birds.
It read: “Whilst there does not appear to be a huge outbreak in our area from what we can tell, we would remind everybody to please be very cautious picking up ill birds at present.
“The risk to humans is small, but if you do find a poorly sea bird, swan, goose, gull or wader, please wear gloves if you intend picking them up.
“Any birds needing to come to the centre, please ring us first so we are aware you are on your way.
“We are still open, but with the Covid situation, and bird flu, we are being extremely careful for the sake of our staff, volunteers, visitors and of course the birds already at the Centre.
“Please remember if you keep poultry, they, like us humans, should still be in lock-down for the time being.”
Bird flu was confirmed in a small flock of poultry from a farm on the Island of Sanday in Orkney at the end of last year.
Bird keepers across Scotland have been told to keep their animals housed properly since then to keep the disease from spreading further.
Scotland’s Chief Veterinary Officer Sheila Voas said the risk to human health from the H5N8 Avian Influenza was very low.
She said: “We have already made clear that all bird keepers – whether major businesses or small keepers with just a few birds – must ensure that their biosecurity is up to scratch to protect their birds from disease and prevent any contact between their birds and wild birds.”