Date of Award

1997

Degree Name

Biology

College

College of Science

Type of Degree

M.S.

Document Type

Thesis

First Advisor

Thomas K. Pauley

Second Advisor

Donald C. Tarter

Third Advisor

Thomas Weaks

Abstract

A 2-year study was conducted to determine the reproductive and nesting habits, embryonic and larval development, and tolerance to acid conditions of Hemidactylium scutatum in West Virginia. Five study sites located in or adjacent to the Otter Creek National Wilderness Area, Monongahela National Forest, Randolph County, West Virginia, were monitored to determine nesting habits and length of incubation and larval periods in Hemidactylium Time of breeding was determined by spermatogenic wave analysis and time of egg deposition was determined by examination of ovarian follicles and field observations of gravid females migrating to nest sites. Breeding occurred in autumn and again in spring when climatic conditions were favorable. Migration to nest sites occurred in early April and oviposition occurred in mid-April to early May. Nests were found within 25 em of permanent and temporary pools adjacent to wooded areas in the following 3 substrate types: Sphagnumsp. moss, non-Sphagnumsp. moss, and Eriophorum virginicum roots. A 7 to 8 week incubation period was followed by a 9 to 10 week larval period that ended in mid-August Eggs were laid with a mean diameter of 3.7 mm and hatched with a mean diameter of 6.3 mm. Larvae averaged 8.9 mm snout-vent length (SVL) and 12 to 15 mm total length (TL) at time of hatching and 13.3 mm SVL and 16.6 mm TL at transformation. Larvae had the following 4 morphologically distinct developmental stages: 1) post-embryonic; 2) growth; 3} gill resorption; and 4)transformation. Eggs and larvae developed normally in both neutral and acid environments. Rana sylvatica embryos and Hemidactylium embryos and larvae were tested in the laboratory to determine their tolerance to low pH conditions. The 96-hour Tim (median tolerance limit) test was used as the measure of acute toxicity to low pH. Regression analyses revealed that Hemidactylium embryos were more tolerant of acid conditions than larvae and R. sylvatica embryos.

Subject(s)

Hemidactylium - West Virginia.

Salamanders - West Virginia.

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