Action: Asian clams: Drain the invaded water body
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- No evidence was captured for the use of dewatering as a management tool for Asian clams.
'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.
The relatively thick shells of Asian clams Corbicula spp. will offer protection against desiccation, but prolonged periods of dewatering may serve as an effective management tool in some situations. Large die-offs of Asian clams have been reported during droughts (Ilarri et al. 2011). Also, an ecological study conducted between 2005 and 2006 in Lake Constance, which borders Germany, Switzerland and Austria (Werner & Rothhaupt 2008) found that an Asian clam Corbicula fluminea population was adversely affected by unprecedented low water levels and a harsh winter with consequently low water temperatures. Low water levels led to 100% mortality in clams situated at mean low-water level due to desiccation. At lower depths, water temperatures as low as 2oC over a three month period led to a mass die out of the clams. Juvenile clams survived longer than adults. However, at the end of winter, only 1% of the population remained. Although an intervention was not directly tested in this study, the results suggest that low temperatures and drainage may be possible methods of controlling Asian clam populations in the wild. In regulated rivers, it may also be possible to decrease the flow rate in order to reduce the water level and control Asian clam populations.
Bódis E., Tóth B. & Sousa R. (2014) Massive mortality of invasive bivalves as a potential resource subsidy for the adjacent terrestrial food web. Hydrobiologia, 735, 253-262.
Ilarri M., Antunes C., Guilhermino L. & Sousa R. (2011) Massive mortality of the Asian clam Corbicula fluminea in a highly invaded area. Biological Invasions, 13, 277–280.
Werner S. & Rothhaupt K.–O. (2008) Mass mortality of the invasive bivalve Corbicula fluminea induced by a severe low-water event and associated low water temperatures. Hydrobiologia, 613, 143–150.