Phenotypic correlates of post-fledging dispersal in a population of greater flamingos: the importance of body condition

1. Factors influencing post-fledging movements before the first breeding attempt were studied in individually marked greater flamingos (Phoenicopterus ruber roseus ) born in the Camargue, southern France, between their natal area and their principal wintering grounds (Spain, Sardinia, Tunisia and France) from 1995 to 1999. 2. We tested whether post-fledging dispersal was affected by sex, age, year, body condition, body mass and tarsus length using a multistate capture-recapture modelling approach. We focused particularly on the hypothesis that increased movement probabilities were associated with good and poor body condition. Because long-distance dispersal is energetically expensive and may involve a high risk of mortality, the acquisition of a robust physical condition prior to dispersal probably plays a critical role in determining the extent to which animals disperse. At the other extreme, birds in poor condition either leave their natal area or starve, which should result in relatively high dispersal rates. 3. Movement probabilities were not sex-dependent, but were age-dependent with high movement probabilities during the first year of life (above 0.6) and low probabilities after the first year (0.055). Movement probabilities also differed between years and localities. 4. Movement probability from the natal area was related to the body condition (and body mass) of the fledglings, with a high movement probability (0.873) when juveniles were in good body condition, and a relatively lower probability (from 0.629 to 0.724) when juveniles were in poorer condition. The proportion of variability in dispersal explained by body condition and body mass were 90.9% and 63.5%, respectively. 5. Results support the hypothesis that condition affects dispersal patterns from the natal area. They also suggest that body condition and local environmental conditions during the early growth play a role in dispersal.