PLASMA-CORTICOSTERONE AND TESTOSTERONE LEVELS DURING THE ANNUAL REPRODUCTIVE-CYCLE OF MALE BROWN ANOLES (ANOLIS-SAGREI)

The objective of the present study was to determine the plasma levels of testosterone and corticosterone in male Anolis sagrei during the an nual reproductive cycle and to examine the relationships between seaso nal change in the levels of these hormones, male reproductive activity , and body condition. Both testosterone and corticosterone levels in a dult males captured in the Miami, Florida, area varied significantly w ith month and with season (i.e., breeding vs. nonbreeding period), alt hough they were not significantly correlated with each other or with b ody mass. Mean monthly testosterone levels were higher during the bree ding season (March-August) than during the nonbreeding season, with th e one exception that the highest mean testosterone level occurred in F ebruary immediately before the beginning of the breeding season. Testo sterone levels in the overall sample of 144 males were significantly c orrelated with testes mass but not with any of the other measured vari ables. Corticosterone levels were highest during the nonbreeding seaso n and lowest during the breeding season. Corticosterone levels on a mo nthly basis were negatively correlated with monthly changes in testes mass and positively correlated with monthly changes in abdominal fat-b ody mass.