To understand how rates of growth interact to result in sexual dimorphism in the Black salamander, Aneides flavipunctatus, I conducted a mark–recapture study in Mendocino County, California. Five hundred captures (420 unique animals plus 80 recaptures over four occasions) were measured (body length, head width, head length) and released. Adult males and females are not sexually dimorphic in body length, but are dimorphic in head width; males have wider heads compared to females. From 80 recaptures, growth rates were determined for body length and head size. As expected, juveniles grow faster relative to adults; growth rates decrease as body size increases. Adult males and females have similar growth rates of body length. Males and juveniles have greater head-width growth rates compared to adult females. Head size dimorphism in A. flavipunctatus is a result of a higher head growth rate in males at sexual maturity relative to females. Because body growth rates are not significantly different between adult males and females, adult salamanders of similar size are of similar age. The Von Bertalanffy growth model fit to the mark–recapture growth data conservatively predicts that salamanders of 79 mm snout–vent length are 18 years old. Because of certain assumptions of the model, the oldest salamanders in the population are more likely to be up to 25–30 years old.
You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither BioOne nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the BioOne website.
Vol. 104 • No. 1