Adaptive benefits of differential post-fledging development patterns in the Lesser Flamingo (Phoenicopterus minor)

Measurements of five morphological components (mass, skull length, culmen, flattened wing and tarsus) and blood samples were taken from 154 fledged wild Lesser Flamingos Phoenicopterus minor captured during 2001 and 2002 at Lake Bogoria, Kenya (0°11'–20'N, 036°06'E). The sample included adults (>3 years old), immature birds (2–3 years old) and first-year juvenile birds of both sexes. The sex of each bird was determined by PCR amplification of the CHD-Z and CHD-W genes, using DNA extracted from blood samples. Within each gender, there were significant differences in mass and tarsus length amongst the three age groups, indicating that the skeletal size and mass of Lesser Flamingos continue to increase between fledging and attainment of adult plumage at three to four years of age. The different morphological components increased in size at different rates, although the same components appeared to increase at similar rates in both males and females. Skull and culmen lengths had reached adult size in juvenile birds, while juvenile wing length, tarsus length and mass were approximately 95%, 85% and 75% of adult size, respectively. The adaptive significance of these findings is discussed. © 2006 Taylor and Francis Group, LLC.