Alternative Demographic Models for Two Populations of the Seal Salamander, Desmognathus monticola

Abstract

Variation among desmognathan salamanders in the timing of the female reproductive cycle is poorly understood. Although nesting tends to be seasonal, in the warmer months, females may not reproduce on a strictly annual cycle, but on a biennial or irregular schedule. In the present report, I examine the ramifications of annual and biennial female reproductive schedules on demography in two populations of Desmognathus monticola in the southern Blue Ridge Mountains of southwestern North Carolina. Provisional demographic models for each are developed based on published data on age structure, growth and developmental rates, and fecundity in the populations in question. The models indicate that biennial reproduction would require higher first-year survival than annual reproduction, at levels that appear tenable given our understanding of the ecology of nesting females and larvae of this species.