A Factor Analysis of Seasonal, Behavioral, Hormonal and Body Weight Changes in Adult Male Barheaded Geese, Anser Indicus

Individual measurements of courting, aggression, pairbond displays, body weights and the circulating levels of testosterone, LH, T4 and prolactin in male barheaded geese were subjected to a factoral analysis. Data from the whole year were analysed and then broken up into pre-breeding and post-breeding components and re-analysed. Some parameters remained clumped in the same factors throughout like aggression and pair-bond displays, LH and testosterone, and prolactin and body weight. Others, especially behavioral and endocrinological parameters were only linked on either an annual or seasonal basis.