• Androgen and glucocorticoid production in the male killer whale (Orcinus orca): influence of age, maturity, and environmental factors

      O'Brien J. K.; Steinman K. J.; Fetter, G. Alan; Robeck T. R. (2016)
      Circulating concentrations of testosterone and its precursor androstenedione, as well as dehydroepiandrosterone (DHEA ) and the adrenal hormones cortisol and corticosterone were measured at monthly intervals in 14 male killer whales (Orcinus orca ) aged 0.8–38 years. Analyses were performed for examination of the relationships of age, sexual maturation status (STATUS ), season, and environmental temperature (monthly air ambient temperature, A‐TEMP ) with hormone production using a mixed effects linear regression model with animal ID as the random variable....