The effect of constant low temperatures on the survival of Bulinus africanus (Krauss), Bulinus globosus (Morelet) and Biomphalaria pfeifferi (Krauss)

Abstract

The tolerance to low temperature of the freshwater snail species Bulinus africanus, Bulinus globosus and Biomphalaria pfeifferi was experimentally investigated. Snails were exposed to temperatures ranging from 0 °C to 8 °C and their survival was noted daily. The results showed that the survival of the cohorts of all three species decreased as the temperature was lowered in the range investigated. Evidence is presented which demonstrates that B. africanus can withstand cold conditions better than B. globosus, and that B. globosus is better equipped than a pfeifferi in withstanding low water temperatures.