Breeding experience might be a major determinant of breeding probability in long-lived species: the case of the greater flamingo

The probability of breeding is known to increase with age early in life in many species. Apart from physical maturation, this increase may be due to experience accumulated through successive breeding episodes. However, this question has not been much investigated. We show how recent methodological advances allow to account for the number of previous --possibly unobserved-- breeding episodes. Applying this method to the encounter histories of 14716 greater flamingos over 25 years, we get a detailed picture of the interplay of age and experience. Particularly notable is that breeding probability of inexperienced birds is always at least 3 times lower than that of same age experienced birds, and that one additional breeding experience is much more valuable than one additional year of age. Another pattern, that breeding probability of birds with <2 experiences drops after age 8, may point either to phenotypic heterogeneity or to the end of a sensitive period for acquiring behavioral skills. These results hold when controlling for the sex and for individual differences. All in all, the role of experience appears major in this species. Overlooking experience may hamper the detection of trade-offs and the assessment of individual heterogeneity. More importantly, experience may be a major factor in determining the optimal age of first breeding. However, manipulative experiments are desirable to confirm this finding.