Date of Award

12-2010

Document Type

Thesis

Degree Name

Master of Science (MS)

Department

Biology

First Advisor

Jeffery Larkin, Ph.D.

Second Advisor

Tim Nuttle, Ph.D.

Third Advisor

William Brenneman, Ph.D.

Fourth Advisor

Joseph Duchamp, Ph.D.

Fifth Advisor

John J. Cox, Ph.D.

Abstract

Salamanders are integral parts of forest ecosystems, often exceeding the combined biomass of all other vertebrates. They are often used as indicators of ecosystem health due to their intimate relationship with soils and water and their sensitivity to habitat alteration. This is especially important considering logging practices are un-regulated around ephemeral streams. This study examined salamander community composition in unstudied ephemeral stream areas, in order to identify important habitat characteristics associated with salamander abundance and diversity. Such information may aid in the development of improved forestry practices in and adjacent to ephemeral streams. From March 2007 to May 2008, I surveyed a total of 12 stream segments monthly. I detected 780 salamanders from 10 species, with an average of 65 (±35.8) salamanders per stream segment (minimum 17, maximum 127) with slimy, ravine and eastern newt comprising 78% of the total detections. I also intensively surveyed habitat characteristics in each ephemeral stream channel and along their banks. A linear regression, analyzing salamander species diversity and habitat variables, limited to the inclusion of two habitat variables per model, produced 7 competing models. The important variables (IV >0.4) from those models were density of small rocks and large rocks in the stream bed. When these salamander abundances were compared to habitat data, via redundancy analysis (RDA) and then a forward stepwise variable selection, two habitat variables were revealed to be important to the abundance of the salamander species. These variables included 1) the area of coarse woody debris in the stream; 2) a composite variable consisting of stream width, decay class, and number of coarse woody debris objects in stream. My study revealed that ephemeral streams provide suitable conditions to support diverse forest salamander communities. As such, my findings warrant the development of forestry best management practices for ephemeral streams that consider the maintenance of habitat quality and associated salamander communities.

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