People are being asked to join the "puffarazzi" and photograph puffins with fish in their bills to help find out what the seabirds are feeding their young.
The citizen science scheme was first run by the RSPB in 2017, with 602 people sending in 1402 photos of the seabirds from almost 40 colonies.
The RSPB says the pictures have helped scientists identify areas where puffins are struggling to find the large nutritious fish which they need to feed their chicks, or pufflings.
34,000 puffins are known to breed in Wales at the last count in 2017-25,000 of these found on Skomer Island, off Pembrokeshire. They are also found at Skokholm, Bardsey Island, Puffin Island and RSPB South Stack.
The RSPB said action was needed to make sure the bird continues to have a future in Wales.