Crayfish Predation on Corbicula under Laboratory Conditions

Publisher Website
Google Scholar
Abstract
Crayfish predation on the Asiatic clam Corbicula was examined in laboratory aquaria. In 1 study, 20 Procambarus clarkii in separate 15 liter aquaria were offered intact live clams, 4-20 mm shell length (SL), at temperatures of 20.degree. C for 14 days. Only clams < 6 mm were consumed. Mean sustained feeding rate on 4-6 mm (SL) clams by P. clarkii which fed daily (n = 8) was .apprx. 11 clams/day (or .apprx. 0.3% of the mean crayfish body wet weight). In a 2nd study, 8 Cambarus bartonii in separate 75 liter aquaria were offered large Corbicula (24-35 mm SL) with naturally occurring or artificially produced shell perforations of 2 sizes at temperatures of 20.degree. .+-. 1.degree.C for 8 days. C. bartonii readily fed on clams with perforations large enough (4-6 mm for large crayfish) to permit insertion of the 1st walking leg. The mean sustained rate of feeding was .apprx. 1.5 clams/day (or about 4% of mean crayfish body wet weight). C. bartonii were also observed to feed readily on intact Corbicula (< 9 mm SL). Small intact Corbicula and large damaged Corbicula can be eaten by crayfish in the laboratory. Consumption rates of large damaged Corbicula indicate they could be an important food resource. Damaged Corbicula were observed in large numbers only in the tailwaters of a hydroelectric generating station, although they may occur in other habitats such as wave-swept beaches and fast-flowing streams. The value of this food resource may be restricted. Small intact Corbicula are more widely distributed a food for crayfish may also be restricted if results with P. clarkii are typical of crayfish in general. Even at those consumption rates the number of small clams consumed per m2 could be high where crayfish densities are high, if Corbicula were the primary food.

This publication has 5 references indexed in Scilit: