Cold,freezing, and desiccation tolerance of the limpet Acmaea digitalis (Eschscholtz)

Cold, freezing, and desiccation tolerance were examined in the limpet, Acmaea digitalis (Eschscholtz). Fifty percent of the experimental population survived freezing at temperatures between ?10 ° and ?12 °C for at least 24 hr. In this temperature range, 60–80 % of the body water was frozen. The LD₅₀ for water loss by desiccation was 76.5% ± 1.3_δ. At 70–80% body water loss, solutes were concentrated between 350 and 500%. Some limpets failed to survive immersion in 450% seawater for 6 hr (100% scawater = salinity of 31‰), suggesting that much of the damage from freezing and desiccation was from an increased solute concentration. No glycerol could be detected in extracts of the foot and the visceral mass of A. digitalis during winter, confirming similar results in studies carried out on other intertidal molluscs.