Common Guillemots Uria aalge successfully feed two chicks
Harris, M.P., Bull, J., & Wanless, S. (2000) Atlantic Seabirds 2(2):92-94
A pair of Common Guillemots Uria aalge with a small chick adopted a second and successfully reared both to normal fledging age. A single day's feeding watch suggested that the pair doubled the normal feeding rate and the adults spent little time together at the nest-site, though the chick was never left unattended.
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