Term of Award

1998

Degree Name

Master of Science in Biology

Document Type and Release Option

Thesis (open access)

Department

Department of Biology

Committee Chair

C. Ray Chandler

Committee Member 1

Steve Vives

Committee Member 2

Lorne M. Wolfe

Abstract

Salamanders are important components of many forested communities. However, their fossorial habits and seasonality often make them difficult to sample. The use of artificial coverboards (coverboards) is a relatively new and little-studied technique for monitoring the terrestrial activity of salamanders Coverboards are designed to simulate fallen tree limbs and logs, and to provide a moist refuge for forest salamanders. Despite several studies, questions remain concerning the value of coverboards. Therefore, I conducted an experiment in 1996-1997 to determine whether coverboards are as effective for sampling salamanders as searching natural cover objects such as logs and branches. Using a paired design, I established five sites, each containing two 1-ha grids separated by 20 m. One of the grids contained only natural debris while the other grid contained natural debris and 100 individually numbered coverboards (30.4 x 30.4 x 2 cm) each placed 10 m apart. During the spring (26 April - 6 June) and fall (25 September - 7 November) of 1997, the paired grids (coverboards and natural cover) were checked every 1-2 weeks at each site for any salamander species.

Encounter rates were significantly lower under coverboards (0.8 salamanders per site check ±0.15 SE) than under natural cover (2.3 salamanders per site check ±0.34 SE). However, searches under coverboards detected most of the same species (Plethodon glutinosus ocmulgee, Eurycea cirrigera, E. quadridigitata, and E. guttolineata) as found under natural cover (P. g. ocmulgee, E. cirrigera, E. quadridigitata, E. guttolineata, and Ambystoma opacum). Salamander size/age under coverboards (mean=4.32 cm ±0.22 SE) was also the same as salamander size/age under natural cover (mean=4.34 cm ±0.33 SE). The number of salamanders found under coverboards was dependent on rainfall and site. Coverboards did not reproduce the same physical characteristics of natural cover. The temperature under coverboards fluctuated more than the temperature under natural cover.

This is the first comparative study to quantify salamanders sampled by an array of coverboards and that sampled by an adjacent grid of natural cover objects. It was also the first to quantify the thermal microclimate under coverboards compared to natural cover. Overall, my results show that coverboards can effectively sample salamanders that normally occur under natural cover (in terms of species and size/age), although they detect fewer individuals. There is a positive relationship in the number of salamanders encountered under coverboards and rainfall in southeast Georgia.

OCLC Number

1029292843

Copyright

This work is archived and distributed under the repository's standard copyright and reuse license for Theses and Dissertations authored 2005 and prior, available here. Under this license, end-users may copy, store, and distribute this work without restriction. For questions related to additional reuse of this work, please contact the copyright owner. Copyright owners who wish to review or revise the terms of this license, please contact digitalcommons@georgiasouthern.edu.

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