Action: Asian clams: Change temperature of the water
- A controlled laboratory study in the USA found that temperatures of 36°C or higher killed Asian clams within or after four days.
All organisms will have an upper thermal tolerance and so raising water temperatures may offer a tool for management of Asian clams Corbicula spp. Such an approach may be especially suited to industrial facilities that generate an excess of heated water, such as power plants. Reducing water temperatures can also offer a possible management tool. Studies in the St. Clair River, USA reported very large winter die-offs of Corbicula fluminea (French & Schloesser 1996). Populations persisted in the waters immediately downstream of a power plant in which water temperature was relatively high.
French J.R.P. & Schloesser D.W. (1996) Distribution and winter survival health of Asian clams, Corbicula fluminea, in the St. Clair River, Michigan. Journal of Freshwater Ecology, 11, 183-192.
Supporting evidence from individual studies
A controlled laboratory study conducted between 1976 and 1977 on specimens from a river in Virginia, USA (Cherry et al. 1980) found that exposure to temperatures of 36°C and higher killed Asian clams Corbicula fluminea. All clams were dead after either four days at 36°C or two days at 37°C compared with clams surviving in a control treatment at 25°C. Clams were placed in seven heated aquatic chambers, plus one control chamber. In total, 19 clams were placed in each chamber. Over a 24-hour period, infrared lamps raised chamber temperatures to 27, 29, 31, 33, 35, 36 and 37°C. These temperatures were held for four days. A control group was maintained at 25°C. Mortality status of clams was checked and recorded.