Population Dynamics of Pleurocera acuta in a Central Kentucky Limestone Stream
1970; University of Notre Dame; Volume: 83; Issue: 1 Linguagem: Inglês
10.2307/2424007
ISSN1938-4238
Autores Tópico(s)Mollusks and Parasites Studies
ResumoThe stream snail, Pleurocera acuta was studied during a 12-month period in Silver Creek, Madison Co., Kentucky. Substrate was important in the distribution of P. acuta; substrates high in car- bonate offered the most suitable habitats. Distribution was secondarily affected by water depth and current, with the largest populations in shallow areas of relatively slow flow. Overall population density was 38.4/M2, with densities up to 161/M2 in high-carbonate areas. Repro- duction occurred in July and August. Growth was rapid until October, slowed during the winter, then increased in early spring. The species appears to have a two-year life span. Population size varied in direct proportion with the concentrations of dissolved oxygen and alkalinity. The adult sex ratio is 1: 1; females average slightly longer than males. Apical erosion decreased downstream, as did the obesity index due to the increased length of noneroded shells. Shell width increased slightly in the lower part of the stream.
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