Zoo keepers and aquarists at Edinburgh Zoo have started counting the animals in its collection as part of a nationwide exercise to update records.
Penguins take stock of a sign for the annual count
To comply with zoo legislation it is required to keep precise records of every animal's birth, death, arrival and departure.
Keepers are aware of how many animals they have, but the annual check makes sure they have precise figures.
The data goes to the British and Irish Association of Zoos and Aquariums.
The national body offers advice and guidance on all aspects of zoo management and animal welfare.
The records are also available for scrutiny by local authorities who issue and renew the licences for zoos and aquariums.
Biaza's director, Dr Miranda Stevenson, said: "This annual stock-take, although time-consuming and sometimes quite difficult, is just one of the many ways which zoos and aquariums in this country demonstrate their professionalism and attention to detail.
"Keeping precise records of the animals in their care is fundamental to good animal management and contributes hugely to effective conservation breeding programmes, for example."