Individual study: Dynamics and control of the Asiatic clam in the New River, Virginia
Cherry D.S., Rodgers J.H, Graney R.L. & Cairns J. (1980) Dynamics and control of the Asiatic clam in the New River, Virginia. Bulletin of the Virginia Water Resources Center, 123, 1-72
This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.
Asian clams: Change temperature of the water
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.
Asian clams: Add chemicals to the water
A replicated laboratory study conducted between 1976 and 1978 on specimens from a river in the USA (Cherry et al. 1980) found that Asian clams Corbicula fluminea, were killed when exposed to concentrations of chlorine, potassium and heavy metals. Half of the clams died after exposure to 0.69 mg per litre of chlorine in tanks for 10 days. Up to 89% died within four days of exposure to 140 mg per litre of potassium. Copper was the most toxic with half of the clams dying when exposed to 0.59 mg per litre for one day and 0.04 mg per litre for four days. The toxicity of several biocides was tested in static and continuous-flow tests. Fourteen replicate tanks and four artificial streams were used, respectively. There were 12 clams per tank and nine clams per artificial stream (flow rates were maintained at 0.5-0.8 litres/min). Clams were exposed to various concentrations of chlorine, potassium and copper for between one and 10 days. Survival of clams was checked and recorded.