Management Tools for Dreissenid Mussels
Dreissenid mussels have posed an aquatic invasive species challenge in the United States since their arrival in the Great Lakes in the 1980s. Zebra (Dreissena polymorpha) and Quagga (D. bugensis) mussels are filter feeders with high reproductive capacity. Their behaviors result in altered nutrient cycles, shifts in trophic structures, and extirpation of some native species in systems where they have established. Efforts to manage dreissenid populations have targeted adult stages of the mussel; however, treatments that target the veliger stage can reduce the cost of application, minimize adverse effects to nontarget organisms, and use lower concentrations of a control agent. Resource managers need a range of tools at their discretion to control all life stages of dreissenids. Low dose copper applications, carbon dioxide, and microparticle delivery of toxicants are being evaluated for their ability to reduce the populations of dreissenid mussels.
--------------------------------------------------------
Evaluation of Copper as a Control Agent for Invasive Mussels
Principal Investigator – Diane Waller
USGS researchers and partners conducted an experimental application of low dose copper, as EarthTecQZ, to a bay in Lake Minnetonka, MN. The veliger density and settlement were compared to that of an untreated bay within the same lake. The copper application produced a substantial reduction in zebra mussel abundance of early life stages, juvenile settlement and even live adults in the treatment bay, compared to the control bay. Follow up monitoring will be conducted to determine how long the treatment will suppress zebra mussel populations and the recovery response of native invertebrate communities. Further testing will be conducted to determine minimal effective concentrations of copper needed for zebra mussel suppression and long-term effects on native communities.
-------------------------------------------------------
Evaluation of Carbon Dioxide to Control Dreissenid Mussels
Principal Investigator – Diane Waller
Carbon dioxide (CO2) has been suggested as a chemical control for a variety of invasive aquatic organisms, including Asian Carp. USGS researchers and partners evaluated the efficacy of low CO2 concentrations for preventing zebra mussel larval (veliger) settlement during summer 2019 in a harbor of the upper Mississippi River. The lowest CO2 concentration that was tested was effective for preventing all mussel settlement during the summer. Impacts to native species, including unionid mussels and aquatic macroinvertebrates, were minimal. USGS will partner with Bureau of Reclamation (BOR) and U.S. Fish and Wildlife Service (FWS) to explore application scenarios for CO2 in closed and open systems to prevent dreissenid settlement.
----------------------------------------------------------
Development of Selective Control Tools
Principal Investigator – Diane Waller
Currently, dreissenid mussel populations are spreading and becoming a growing problem in many aquatic systems, making it important to find management techniques that are selective for the invasive mussel populations while leaving the native populations intact. Control technology for dreissenids in open water currently relies on a limited number of molluscicides that must be applied within or under a containment barrier to achieve effective concentration. These applications can be costly and adversely impact nontarget species. Microparticle methods are in development that will target delivery of a control tool to dreissenid mussels and reduce impacts of nontarget organisms, including fish and native mussels. This technology could potentially be efficacious without the need for a containment barrier.
Dreissenid mussels have posed an aquatic invasive species challenge in the United States since their arrival in the Great Lakes in the 1980s. Zebra (Dreissena polymorpha) and Quagga (D. bugensis) mussels are filter feeders with high reproductive capacity. Their behaviors result in altered nutrient cycles, shifts in trophic structures, and extirpation of some native species in systems where they have established. Efforts to manage dreissenid populations have targeted adult stages of the mussel; however, treatments that target the veliger stage can reduce the cost of application, minimize adverse effects to nontarget organisms, and use lower concentrations of a control agent. Resource managers need a range of tools at their discretion to control all life stages of dreissenids. Low dose copper applications, carbon dioxide, and microparticle delivery of toxicants are being evaluated for their ability to reduce the populations of dreissenid mussels.
--------------------------------------------------------
Evaluation of Copper as a Control Agent for Invasive Mussels
Principal Investigator – Diane Waller
USGS researchers and partners conducted an experimental application of low dose copper, as EarthTecQZ, to a bay in Lake Minnetonka, MN. The veliger density and settlement were compared to that of an untreated bay within the same lake. The copper application produced a substantial reduction in zebra mussel abundance of early life stages, juvenile settlement and even live adults in the treatment bay, compared to the control bay. Follow up monitoring will be conducted to determine how long the treatment will suppress zebra mussel populations and the recovery response of native invertebrate communities. Further testing will be conducted to determine minimal effective concentrations of copper needed for zebra mussel suppression and long-term effects on native communities.
-------------------------------------------------------
Evaluation of Carbon Dioxide to Control Dreissenid Mussels
Principal Investigator – Diane Waller
Carbon dioxide (CO2) has been suggested as a chemical control for a variety of invasive aquatic organisms, including Asian Carp. USGS researchers and partners evaluated the efficacy of low CO2 concentrations for preventing zebra mussel larval (veliger) settlement during summer 2019 in a harbor of the upper Mississippi River. The lowest CO2 concentration that was tested was effective for preventing all mussel settlement during the summer. Impacts to native species, including unionid mussels and aquatic macroinvertebrates, were minimal. USGS will partner with Bureau of Reclamation (BOR) and U.S. Fish and Wildlife Service (FWS) to explore application scenarios for CO2 in closed and open systems to prevent dreissenid settlement.
----------------------------------------------------------
Development of Selective Control Tools
Principal Investigator – Diane Waller
Currently, dreissenid mussel populations are spreading and becoming a growing problem in many aquatic systems, making it important to find management techniques that are selective for the invasive mussel populations while leaving the native populations intact. Control technology for dreissenids in open water currently relies on a limited number of molluscicides that must be applied within or under a containment barrier to achieve effective concentration. These applications can be costly and adversely impact nontarget species. Microparticle methods are in development that will target delivery of a control tool to dreissenid mussels and reduce impacts of nontarget organisms, including fish and native mussels. This technology could potentially be efficacious without the need for a containment barrier.