Intrinsic Male Mating Capacity Is Limited in the Plethodontid Salamander, Desmognathus ochrophaeus

Abstract

This research investigated the intrinsic male mating capacity of the salamander Desmog- nathus ochrophaeus, where mating capacity is defined as the ability to deposit at least one spermatophore during a sexual encounter. In the first experiment, males were simultaneously presented with two females. Only 10% of the males tested deposited more than one spermatophore in this situation, indicating a low potential for multiple insemination under conditions of excess female availability. In the second exper- iment, a male was paired with a different female each night for five nights. The majority of males tested (87%) deposited a total of only one or two spermatophores over this period. No male deposited more than one spermatophore during any one sexual encounter. In the third experiment, the time interval between two successive sexual encounters was varied from no nights to three nights. A period of recovery of three nights was required if the same number of males were to deposit spermatophores during both encounters. These data indicate that the intrinsic mating capacity of male D. ochrophaeus is limited. It is suggested that the availability of some non-sperm component(s) of spermatophores limits their rate of production.