Behavioural Endocrinology of Breeding Adelie Penguins (Pygoscelis adeliae)

摘要: Measuring hormonal changes is vital for understanding how the social and physical environment influences behaviour, reproduction survival. Various methods of hormone measurement exist, potentially explaining variation in results across studies; should be cross validated to ensure they correlate. I directly compare faecal plasma measurements (Chapter 2), use most suitable endocrine measure test Darling hypothesis 3) that breeding hastened synchronized larger colonies due increased stimulation (mediated by system). Blood samples were simultaneously collected from individual Adelie penguins (Pygoscelis adeliae) comparison, assayed testosterone corticosterone (or their metabolites). Sex differences variability within each measure, correlation values measures compared. For both hormones, showed greater than samples. Males had higher levels females, but difference was only significant Plasma testosterone, not significantly males females. Correlation between sample types poor overall, weaker females males; perhaps because represent hormones are free bound globulins, whereas faeces portion. Faecal also a cumulative over time, as opposed ‘snapshot’ concentration. sampling appears more assessing baseline levels. In second study examined, two seasons, whether timing varied with colony size; present occupants predicted show earlier, synchronous breeding. Baseline throughout season, survival, measured investigate possible proximate ultimate mechanisms results. The influence environmental relating breeding, sea ice conditions. Colony size did or synchrony