Survival and non‐breeding of adult Common Guillemots Una aalge

• Published in: Ibis
• Main Authors: HARRIS, M. P., WANLESS, S.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 1995
• Subjects: Uria aalge; uria
• Online Access: http://dx.doi.org/10.1111/j.1474-919x.1995.tb03239.x; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fj.1474-919X.1995.tb03239.x; https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1474-919X.1995.tb03239.x

Annual survival of colour‐ringed Common Guillemots Uria aalge with at least 1 year of breeding experience was measured in five study areas on the Isle of May, southeast Scotland from 1982 to 1993. Annual survival averaged 94.9%. There were no significant sex, year or area differences. Between 5% and 10% of the birds known to be alive in any year did not breed, and on average such birds appeared to survive less well (87%) than breeders (95%). Non‐breeding did not occur randomly within the population, and 6% of birds accounted for 47% of the cases of non‐breeding. It appeared that non‐breeding in Common Guillemots on the Isle of May was socially induced with most cases occurring after an individual had lost its site.