Asiatic clams (Corbicula manilensis Philippi) were sampled at twelve stations randomly located along a 16-km stretch of the Wekiva River, Florida, every three months fro August 1976 to June 1977. Clams were found at most stations. Their abundance ranged from 4 to 1210 per m2. Mean numbers of Corbicula were highest at stations where the bottom sediments were primarily sand and lowest at stations where the bottom sediments were silt and decomposing organic matter. A linear relationship between water temperature, water depth, current velocity, total alkalinity, and pH, and the abundance and distribution of Corbicula was not evident. Seasonally, the abundance of Corbicula was highest in August 1976 and lowest in December 1976. The small size of the specimens suggest a recent invasion of Corbicula into the Wekiva River. The mean shell length of Corbicula in the river was 13.5 mm. The shell lengths of the largest clams ranged from 25.3 mm to 27.2 mm. Large clams were collected in December 1976 (mean shell length = 13.7 mm), whereas small clams were collected in March 1977 (mean shell length = 13.1 mm). Shell width and shell length were linearly correlated (r - 9.98 to 0.99), as were shell breadth and shell length (r = 0.96 to 0.99). The correlation between shell length and the number of rings on the shell was lower (r = 0.68 to 0.88). Clams with smaller rings (more rings per unit length) were found at downstream stations, where abundance was hing, whereas clams with larger rings (fewer rings per unit length) were found at upstream stations, where abundance was low. The data suggest that relationships between age and size depend on the habitat in which the organisms live.
| Identifer | oai:union.ndltd.org:ucf.edu/oai:stars.library.ucf.edu:rtd-1418 |
| Date | 01 January 1979 |
| Creators | Gottfried, Peter K. |
| Publisher | University of Central Florida |
| Source Sets | University of Central Florida |
| Language | English |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | Retrospective Theses and Dissertations |
| Rights | Public Domain |
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