Post-Breeding Emigration and Habitat Use of Radio-Implanted Jefferson and Spotted Salamanders at the Marsh-Billings-Rockefeller National Historical Park

Faccio, Steven

During the past decade, apparent amphibian declines, increased malformation rates, and local extinction events have resulted in global concerns for conservation of amphibian populations. Development of strategies to address these complex issues has been complicated by a lack of solid data to guide conservation efforts. The post-breeding movement patterns, emigration distances, and terrestrial habitat use of two sympatric mole salamander species was investigated using radio-implant procedures. Sixteen adult salamanders (8 Jefferson and 8 spotted) were radio tracked for an average of 164 days. No mortality was documented among the study animals, and eleven individuals were tracked to overwintering sites. Although emigration occurred during spring, summer, fall, or it did not occur, most animals emigrated during June and July. Small mammal burrows were used almost exclusively as terrestrial refuges, and those of the short-tailed shrew were used most frequently, particularly between spring and fall. Deeper tunnels of Perornyscus spp. were more commonly used during winter, suggesting both mammal species are important to maintaining viable populations of these salamanders. The mean emigration distance from release site for both species was 11 1.9 m. Among emigrants, females moved significantly farther than males, and there was a significant relationship between mass and distance moved for spotted salamander, but not for Jefferson salamander. Among eleven salamanders that were from known breeding pools, the mean emigration distance from pool edge was 112.8 m for both species combined. Assuming the mean distance encompassed 50% of the population, an area encompassing 95% of the population would extend 157.1 m from the pool's edge. A regional salamander "life zone" that would encompass 95% of most populations of these two species was calculated by combining emigration distance data from this study with those for Jefferson and spotted salamanders from other studies, resulting in an area that would extend 175 m from a pool's edge. Forest management practices in the landscape surrounding amphibian breeding pools must consider this life zone in management strategies in order to conserve local biodiversity and wildlife values associated with amphibian breeding pools.

Post-Breeding Emigration and Habitat Use of Radio-Implanted Jefferson and Spotted Salamanders at the Marsh-Billings-Rockefeller National Historical Park

Collections