Date of Award

1991

Degree Name

Biological Sciences

College

College of Science

Type of Degree

M.S.

Document Type

Thesis

First Advisor

Thomas K. Pauley

Second Advisor

Leonard J. Deutsch

Abstract

The distribution of P. richmondi and P. cinereus has been of interest to herpetologist for many years. Plethodon cinereus is found throughout the state except for part of the Allegheny Plateau Province where P. richmondi occurs. There is a somewhat abrupt end to their ranges where they overlap which does not appear to be influenced by elevational differences, vegetation patterns, or general climatic changes. The propose of this study was to determine if temperature and/or moisture are limiting the distribution of P. richmondi and P. cinereus in West Virginia. The natural history of P. richmondi has not in West Virginia therefore, some aspects of the natural history were examined in northwestern West Virginia.

Two study areas were employed. One in the P. richmondi range and the other in the P. cinereus range. Environmental data including air temperature, soil temperature, and air relative humidity were collected from both study sites. In the P. richmondi site data were collected from three positions in 6 quadrats and in the P. cinereus area data were collected from each collection site within three belt transects. According to Lee et. al ( 1977), there is an east-to-west increase of temperature with a subsequent decrease in precipitation along the Allegheny Plateau Province. Micro-climatic data such as air temperature, soil temperature, and air relative humidity show a significant difference in these two environmental parameters. Laboratory studies including Critical Thermal Maxima (CTM) and dehydration rates revealed that P. richmondi has higher CTM values and higher dehydration values than P. cinereus. The CTM values were not significant but the dehydration values were significant. This would suggest that moisture plays a more important role in regulating the distriubtion of these two species in West Virginia. However, when salamanders were tested in a moisture gradient, there was no preference for moisture regimes between the two species and it was concluded that they were trying to escape rather than select a moisture regime.

Competition studies were preformed between the two species. A total of 20 interspecific trials were performed between adults following the techinques of Jaeger (1980). It appears that both male and female P. richmondi were better competitors and defeated P. cinereus during laboratory tests. This would explain why P. cinereus has not expanded its range into western West Virginia. However, Nagel (1977) suggests that P. cinereus usually have higher population densities which could prevent P. richmondi from extending its range into eastern West Virginia.

Some aspects of the natural history including seasonal activity, movement patterns, objects, of P. richmondi were studied at North Bend State Park. A total of 100 P. richmondi were observed in and around the quadrats throughout the study. It appears that adult P. richmondi are more active during fall and winter months when air and soil temperatures are cooler. However, one year old juveniles prefer the hotter months during spring and summer. There was no significant difference in the ratio of males to females. Air relative humidity did not appear to be an important environmental regulating factor with respect to seasonal activity although, moisture was important in determining when the salamanders moved into the leaf litter. Thirty-seven specimens were toe-clipped in the quadrats and 5 were recaptured. Of these five, the farthest distance any salamander moved was 5.56 m. Of the specimens observed, 96.8% were found under cover objects and of these, 62.5% under rocks, 31.3% under leaves, and 3.2% under logs.

Subject(s)

Woodland salamanders – West Virginia.

Salamanders – West Virginia.

Woodland salamanders – Ecology.

Woodland salamanders – Morphology.

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