Cooperative Fish and Wildlife Research Units Program: Idaho
Education, Research and Technical Assistance for Managing Our Natural Resources

The National Park Service (NPS) has identified a need for methods that can be used to protect the integrity of natural systems from invasive species. Of particular concern is the release of organisms in residues and within the ballast of shipping tanks in the Great Lakes. These studies are part of a multidisciplinary team effort in the US Geological Survey (USGS) to test the efficacy and safety of using high pH treatments as a rapid and easily reversible treatment to kill invertebrates and other target organisms. Our studies are the direct result of a successful bench scale testing of a treatment proposed by Dr. Barnaby Watten and colleagues at the US Geological Survey’s Leetown Science Center. The Great Lakes Initiative (GSI) conducted bench-scale tests of the efficacy of elevated pH in sodium hydroxide treated water and concluded pH levels of 11.5 to 12.5 were effective in killing rotifers, daphnia, and copepods within 4 hours of exposure (Ten Eyck 2009). Studies detailed in this proposal will develop laboratory tests to determine appropriate protocols of dosage, and exposure time to achieve complete mortality of selected more resistant invertebrate species including crustaceans, bivale and prosobranch mollusks, and resistant myxospores, or other propogules in both hydrated lime and sodium hydroxide treated systems. Upon determination of appropriate model species, we will test and refine protocols for testing in laboratory trials. Using an adaptive approach, we will design appropriate procedures and experimental designs for scaled up for trials on board the Ranger III to establish efficacy in field applications of ballast tanks. We will then conduct a minimum of three shipboard field trials to determine the efficacy and feasibility of hydrated lime and/or sodium hydroxide as treatments to disinfect ship ballast systems. If successful this application will provide an inexpensive and effective method for treating ballast systems to assure that no harmful species are released into the environment. This project responds to the NPS priority research needs for development of emergency ballast treatment options to prevent the spread of critical high risk aquatic nuisance species and fish diseases. Over 60% of the introductions of nuisance /invasive species are attributed to ballast water discharges. This research will test tools that can be used to rapidly decontaminate ballast systems with hydrated lime and/or sodium hydroxid, and then rapidly neutralize the solution to assure no environmental effects of the treatment solution. The focus of the research at the University of Idaho Cooperative Fish and Wildlife Research Unit will be to selecting appropriate highly resistant model invertebrate species for testing, and developing efficacious dosing protocols to determine the appropriate dosage and duration to provide complete mortality. The final phase of studies will be to design and conduct field trials with the model test organisms in ballast systems on board a research ship. The research will be part of the training for a master’s student at the University of Idaho.