Relationships between corticosterone concentration and season, time of day and confinement in a wild reptile (tuatara, Sphenodon punctatus).

摘要: Seasonal and daily variation in basal plasma concentrations of corticosterone the effect short-term confinement on concentration were examined wild adult male female tuatara (Sphenodon punctatus) Stephens Island, New Zealand. Males females sampled immediately upon capture at night (active period) showed significant among four seasons year, also between reproductive states same time. Highest seen November, when level gravid about to nest (4.45 +/- 0.66 ng/ml; mean SE) was almost twice that nonnesting time (2.48 0.30 ng/ml). Plasma samples collected from dusk, middle night, dawn, day no either summer or winter. In these samples, positive correlations body temperature log observed males winter, but not season. Mean held cloth bags for 3 h significantly higher than free-roaming controls (P < 0.01), with 23 times, vitellogenic 9 those their respective controls. measured this stress study compared previously published sex steroids individuals. Corticosterone positively correlated progesterone (both sexes), testosterone sexes) estradiol (measured only). summary, have low levels vary seasonally, diurnally. As other reptiles, shows a elevation response confinement.