On the environmental control of oocyte maturation in a plethodontid salamander

Abstract

The relationship between condition and oocyte maturation was experimentally studied in Plethodon cinereus. Gravid females with immature oocytes were collected in September and maintained on different feeding regimes for 180 days. An index of salamander condition was derived. There was no significant relationship between the number of maturing oocytes and condition of the salamander at the end of the experiment, but oocyte size was signifiantly related to condition. A significant regression relationship was found for oocyte number and initial body weight, suggesting that condition may affect oocyte number early in the reproductive cycle. The implications of environmental induction of oocyte number for affecting clutch size and fitness are discussed.