Action: Asian clams: Change salinity of the water
- A controlled, replicated laboratory study conducted in the USA found that Asian clams were killed (100% mortality) when exposed to high salinities (18-34‰).
Elevated levels of salt in the water can cause osmotic stress in Asian clams Corbicula spp., leading to mortality. Increasing the salinity of a waterbody to a very high level is likely to have significant effects on non-target species.
Supporting evidence from individual studies
A controlled, replicated laboratory study conducted in 1978 on specimens from a stream in Florida, USA (Gainey, 1978) found that placing Asian clams Corbicula spp. in high salinity water resulted in 100% mortality. Clams survived in salinities of up to 10% for two months. Salinities between 18 and 34% led to 100% mortality within 10 days. Clams were transferred from a stream to 10 x 6 litre tanks containing stream water to acclimate. Ten clams were placed in each treatment tank. Following initial acclimation, the clams were placed in salinities from 0.5-40 parts per thousand. Valve movements were recorded and survival checked daily. Salinity levels were considered lethal if mortality was observed in at least 50% of the clams.