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Toxicity of a traditional molluscicide to asian clam veligers

Megan J. Layhee·Bahram Farokhkish·Jackson A. Gross·Miho Yoshioka·Adam Sepulveda
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Abstract

Aquaculture and hatchery industries are in need of effective control methods to reduce the risk of spreading aquatic invasive species, such as the Asian clam Corbicula fluminea , through aquaculture and hatchery activities. The planktonic nature of Asian clam veligers enables this life stage to enter water-based infrastructure undetected, including hatchery trucks used to stock fish. Once in hatchery trucks, veligers can disperse overland and establish in previously uninvaded habitats. As a result, there is a need to develop techniques that result in veliger mortality but do not harm fish. In September 2012, we conducted laboratory trials to determine if a molluscicide (750 mg/L potassium chloride and 25 mg/L formalin) commonly used to kill zebra mussel ( Dreissena polymorpha ) veligers in hatchery trucks can also effectively kill Asian clam veligers. We exposed Asian clam veligers to this molluscicide for 1, 3, and 5 h in each of two water types: deionized water and filtered lake water. We found ,20% mortality at the 1-h exposure period and 100% mortality at both the 3-h and 5-h exposure periods, regardless of water type. This laboratory study represents an important step toward reducing the spread of Asian clams by aquaculture facilities.

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Megan J. Layhee, Bahram Farokhkish, Jackson A. Gross, Miho Yoshioka, Adam Sepulveda. 2013-12-01. Toxicity of a traditional molluscicide to asian clam veligers. https://doi.org/10.3996/042013-jfwm-032

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