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C.K. Dodd

Publications and source records attributed to C.K. Dodd.

At least 91 records · Page 5Linked to original sources
USGS1992

Biological diversity of a temporary pond herpetofauna in north Florida sandhills

From 1985 through 1990, the herpetofauna of a temporary pond in an uplands longleaf pine sandhills community in north-central Florida was monitored. A drift fence completely encircled the pond. Animals were captured in pitfall traps and marked as they entered and exited the pond basin. I captured 16 155 individuals of 42 species (16 amphibians, 26 reptiles). The species richness, diversity (using Margalef's Diversity Index) and dominance (using the Berger-Parker Index) varied among years. Between 62.5% and 87.5% of the amphibian species and 65% to 81% of the reptile species were captured in any one year. Daily amphibian capture was positively correlated with rainfall, whereas reptile capture was either not correlated or weakly negatively correlated with rainfall. Hydroperiod duration was not correlated with the numbers of either amphibians or reptiles captured. Neither the amphibian nor the reptile community showed any trends in diversity or dominance indices during the course of the study, although both communities were dominated by a few species. However, the species responsible for community dominance changed somewhat as the study progressed. Assessing the results of this study is hampered by the lack of comparable studies elsewhere, expected natural fluctuations of amphibian populations, and a prolonged drought, especially during the latter stages of the study. The herpetological community at Breezeway Pond does not appear to follow theoretical predictions of community response to stress. Temporary ponds are important centres of herpetofaunal biodiversity in uplands sandhills communities. Long-term studies are needed to monitor the composition, structure, and functional interactions of their resident species.

Biodiversity and Conservation↗
USGS1991

The status of the Red Hills salamander Phaeognathus hubrichti, Alabama, USA, 1976–1988

A total of 144 sites in the Red Hills Physiographic Province in south-central Alabama, USA, were surveyed in 1988 for burrows of the Red Hills salamander Phaeognathus hubrichti . Of 92 sites surveyed in 1976, no change occurred in the habitat at 54 sites, conditions improved at 19 sites and deteriorated at 18 sites following selective or clear cutting. An additional 14 of 52 sites not surveyed in 1976 were adversely affected by logging. Burrows were most often found on high ( x ̄ = 17 m "> x̄= 17 m ), steep ( x ̄ = 50° "> x̄= 50° ), uncut slopes containing a high soil moisture content ( x ̄ = 57% "> x̄= 57% ) and full tree canopy. Slope angle and soil pH did not affect burrow abundance. Burrow openings averaged 10·9 mm high × 15·3 mm wide. Burrow angle was negatively correlated with burrow width and slope angle but low r 2 values indicate that little of the variation was explained by these variables. Burrows were most often found on the upper two-thirds of slopes; burrows on slopes affected by cutting were found in the middle of the slope where they were less prone to disturbance and desiccation. Although most timber companies claim to no longer cut steep slopes in order to protect salamanders, detrimental forestry practices are still occuring. In some instances, Red Hills salamanders survive selective and clear cutting, but the persistence and viability of affected populations remain unknown. Suggestions are made to reduce impacts from forestry operations. Acquisition of 25 sites containing viable salamander populations and retention as a threatened species under United States federal law are recommended.

Alabama↗
USGS1990

Effects of habitat fragmentation on a stream-dwelling species, the flattened musk turtle Sternotherus depressus

The flattened musk turtle Sternotherus depressus has disappeared from more than half of its former range because of habitat modifications to stream and river channels in the Warrior River Basin, Alabama. Only 6·9% of its probable historic range contains relatively healthy populations, and most populations are fragmented by extensive areas of unsuitable habitat. Turtles in the best remaining habitats continue to be vulnerable to disease and human-related disturbance, collecting and habitat modification. These factors lead to population declines and abnormal population structure. Habitat fragmentation, especially in small populations, increases vulnerability to human-caused catastrophes and demographic accidents, and could lead to eventual extinction. The threats facing fragmented populations of this turtle probably parallel those affecting many other stream-dwelling species throughout the southeastern United States.

Biological Conservation↗