Nestling growth and development in the brown falcon, Falco berigora: an improved ageing formula and field-based method of sex determination

摘要: The accurate determination of nestling age and sex is an important tool for studies that examine life-history traits ecological interactions. Despite the widespread distribution brown falcon, Falco berigora, in Australia, morphological criteria sexing nestlings this species have yet to be published development has not been intensively studied. While ageing formula exists, small sample from which it was derived precluded appropriate statistical assessment independence problems other potentially confounding variables such as hatch order sex. This study used a larger free-living account these factors found most reliable measure wing length. Wing length increased linearly with chick age, independent seven examined. Ageing formulae based on before after remiges emerge are presented. In addition, test determining at banding tarsus width, proposed. Nestling chronology also described detail first time. similar Falconiformes; however, too variable useful assigning age. this, within 6 days eldest hatching relative brightness down degree chicks' eyes had opened were amongst lengths. W R Det ge nes n P. M d