The authors would like to thank the staff of the Genoa National Fish Hatchery for the many hours dedicated to propagating the seven species of mussels and for their expert advice, which was integral to the study design and execution. The Wisconsin Department of Natural Resources assisted in the permitting required for the study, and the La Crosse Regional Airport (La Crosse, Wisconsin) allowed us to conduct study operations on their property. The authors thank Mr. Hugh McMath (USGS), who assisted in study conduct as well as data and sample collection. We also thank Mr. Mark Gaikowski (USGS) for his assistance in study design and data analysis.

For more information on the USGS-the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment-visit http://www.usgs.gov or call 1-888-ASK-USGS (1-888-275-8747) For an overview of USGS information products, including maps, imagery, and publications, visit http://www.usgs.gov/pubprodTo order this and other USGS information products, visit http://store.usgs.gov Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.Although this information product, for the most part, is in the public domain, it also may contain copyrighted materials as noted in the text. Permission to reproduce copyrighted items must be secured from the copyright owner.Suggested citation: Luoma, J.A., Severson, T.J., Weber, K.L., and Mayer, D.A., 2015, Efficacy of Pseudomonas fluorescens (Pf-CL145A) spray dried powder for controlling zebra mussels adhering to test substrates: U.S. Geological Survey Open-File Report 2015-1050, 519 p., http://dx.doi.org/10.3133/ofr20151050. ISSN 2331ISSN -1258 AcknowledgmentsThis study was funded through a combination of a Great Lakes Restoration Initiative Grant and U.S. Geological Survey appropriated funds. AbstractA mobile bioassay trailer was used to assess the efficacy of Pseudomonas fluorescens (Pf-CL145A) spray dried powder (SDP) formulation for controlling zebra mussels (Dreissena polymorpha) from two midwestern lakes: Lake Carlos (Alexandria, Minnesota) and Shawano Lake (Shawano, Wisconsin). The effects of SDP exposure concentration and exposure duration on zebra mussel survival were evaluated along with the evaluation of a benthic injection application technique to reduce the amount of SDP required to induce zebra mortality.Groups of zebra mussels were collected from each lake and allowed to adhere to test substrates for at least 15 days before exposure to SDP. Two independent trials were completed at each lake: (1) a whole water column (WWC) application trial was used to evaluate the effects of SDP exposure concentration and exposure duration on zebra mussel survival; and (2) a benthic injection (BI) application trial in which the SDP was injected into the test tanks to determine the efficacy of a benthic injection application technique to reduce the amount of SDP required to induced zebra mussel mortality. Three exposure durations (6, 9, and 12 hours) were evaluated in the WWC trials and a 12-hour exposure duration was evaluated in the BI trials. All trials contained zebra mussels which were removed at the completion of each exposure duration, consolidated into wire mesh cages, and held in the lake for approximately 30 days before being assessed for survival.For all trials, treatment was assigned to each test tank according to a randomized block design (n = 3 test tanks per treatment). The treatment groups included (1) an untreated control group, (2) a group that received an application of 50 milligrams of SDP per liter (mg SDP/L), and (3) a group that received an...

For more information on the USGS-the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment-visit http://www.usgs.gov or call 1-888-ASK-USGS (1-888-275-8747) For an overview of USGS information products, including maps, imagery, and publications, visit http://www.usgs.gov/pubprodTo order this and other USGS information products, visit http://store.usgs.gov Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.Although this information product, for the most part, is in the public domain, it also may contain copyrighted materials as noted in the text. Permission to reproduce copyrighted items must be secured from the copyright owner.Suggested citation: Luoma, J.A., Weber, K.L., Severson, T.J., and Mayer, D.A., 2015, Efficacy of Pseudomonas fluorescens strain CL145A spray dried powder for controlling zebra mussels adhering to native unionid mussels within field enclosures: U.S. Geological Survey Open-File Report 2015-1051, 301 p., http://dx.doi.org/10.3133/ofr20151051. ISSN 2331ISSN -1258 iii AcknowledgmentsThis study was funded through a combination of a U. Table 2. Mean (standard deviation) number of adhering zebra mussels per unionid mussel before and after exposure, percent change of zebra mussel reduction, zebra mussel burden (as percent unionid body weight), and spray dried powder (SDP) reduction coefficient for number of adhering zebra mussels for each treatment group. . AbstractThe efficacy of a commercially prepared spray dried powder (SDP) formulation of Pseudomonas fluorescens (strain CL145A) was evaluated for removing zebra mussels (Dreissena polymorpha) adhering to a population of unionid mussels in Lake Darling (Alexandria, Minnesota). Two groups of unionid mussels were used in the study. Unionid mussels were collected near the test area, weighed, photographed, individually tagged, and randomly allocated to one of nine test enclosures in equal proportions and then divided into two groups. The first group of unionid mussels (Group 1, n = 5 per test enclosure) were indiscriminately selected from each test enclosure and used to estimate the number of zebra mussels adhering to unionid mussels prior to exposure. The second group of unionid mussels (Group 2, n = 22 per test enclosure) were used to evaluate the efficacy of SDP for removal of adhering zebra mussels. Both Group 1 and Group 2 mussels were used to evaluate the effects of SDP exposure on unionid mussel survival.Treatment was assigned to each test enclosure by using a randomized block design. The three treatment groups were tested in triplicate and included an untreated control group and groups that received a single application of 50 or 100 milligrams per liter (mg/L) of SDP based on active ingredient. All treatment concentrations are reported as active ingredient of SDP. Test enclosures were removed at the 8-hour exposure termination. Both Group 1 and Group 2 mussels remained in their assigned exposure loc...

For more information on the USGS-the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment-visit http://www.usgs.gov or call 1-888-ASK-USGS (1-888-275-8747) For an overview of USGS information products, including maps, imagery, and publications, visit http://www.usgs.gov/pubprodTo order this and other USGS information products, visit http://store.usgs.gov Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.Although this information product, for the most part, is in the public domain, it also may contain copyrighted materials as noted in the text. Permission to reproduce copyrighted items must be secured from the copyright owner.Suggested citation: Weber, K.L., Luoma, J.A., Mayer, D.A., Aloisi, D.B., and Eckert, N.L. 2015, Exposure-related effects of Pseudomonas fluorescens (Pf-CL145A) on juvenile unionid mussels: U.S. Geological Survey Open-File Report 2015-1066, 663 p., http://dx.doi.org/10.3133/ofr20151066. ISSN 2331ISSN -1258 ii Test system used for dosing juvenile unionid mussels. Figure 4. AcknowledgmentsThree-section test chamber schematic: inflow section (left), center section containing juvenile unionid mussels (center), and outflow section (right) Representative juvenile unionid mussels displaying active foot movement. The photograph is of Lampsilis cardium juvenile unionid mussels at the end of the 7-day postexposure holding period. . . AbstractThe exposure-related effects of a commercially prepared spray-dried powder (SDP) or freeze-dried powder (FDP) formulation of Pseudomonas fluorescens (strain CL145A) on the survival of seven species of newly metamorphosed (< 72 hours old) freshwater unionid mussels was evaluated. Forty unionid mussels of each species were randomly distributed to test chambers and each species independently exposed for 24 hours to a static dose of either SDP (four species: Lampsilis cardium, Lampsilis siliquoidea, Lampsilis higginsii, and Ligumia recta) or FDP (three species: Obovaria olivaria, Actinonaias ligamentina, and Megalonaias nervosa).Each test chamber was assigned to one of six treatment groups (n = four chambers per group) by using a randomized block design. The six treatment groups included (1) an untreated control group, (2) groups that received applications with nominal target active ingredient (AI) concentrations of 50, 100, 200, and 300 milligrams per liter (mg/L), and (3) a group that received an application with a nominal target AI concentration of 300 mg/L of heat-deactivated test article (300 HD). After a 24-hour exposure period, water inflow to the test chambers was restored, and the unionid mussels were maintained for an additional 7 days before they were assessed for survival.Mean survival of four unionid mussels species exposed to SDP varied among species and treatment groups when compared to the untreated control groups. The results indicate that exposure to SDP-formulated P. fluorescens up to the maximum label conc...

The exposure-related effects of a commercially prepared spray-dried powder (SDP) formulation of Pseudomonas fluorescens, strain CL145A, were evaluated on coldwater, coolwater, and warmwater fish endemic to the Great Lakes and Upper Mississippi River Basins. Nine species of young-of-the-year fish were exposed to SDP for 24 hours by using continuous-flow, serial-dilution exposure systems at temperatures of 12 degrees Celsius (°C; 2 species; Oncorhynchus mykiss [rainbow trout] and Salvelinus fontinalis [brook trout]), 17 °C (3 species; Perca flavescens [yellow perch], Sander vitreus [walleye], and Acipenser fulvescens [lake sturgeon]), or 22 °C (4 species; Micropterus salmoides [largemouth bass], Micropterus dolomieu [smallmouth bass], Lepomis macrochirus [bluegill sunfish], and Ictalurus punctatus [channel catfish]). Treatments, which were nominal target concentrations of SDP (as active ingredient) of 50, 100, 200, and 300 milligrams per liter (mg/L), were continuously applied for 24 hours by the addition of a test article stock solution into the main water inflow of each exposure system's dilution box. The SDPtreated water was then serially diluted through a series of dilution cells before delivery to the test chambers. The exposure concentrations measured were 61.5 to 81.4 percent of the target concentration. After exposure, fish were monitored for 22 days to assess exposure-related latent effects. Analyses of test animal condition factors and survival revealed that a 24-hour continuous dose of SDP affected all species. Calculated concentrations of SDP that would be lethal to 50 percent of the test animals (LC 50) for the coldwater species were 19.2 and 104.6 mg/L for rainbow and brook trout, respectively. The LC 50 's for the coolwater species were 185.4, 176.9 and 8.9 mg/L for yellow perch, walleye, and lake sturgeon, respectively. The LC 50 's for the warmwater species were 173.6, 139.4, and 63.1 for the largemouth bass, smallmouth bass, and channel catfish, respectively. A reliable LC 50 for bluegill sunfish could not be calculated because mortality in the SDP-treated groups did not exceed 20 percent. Further investigations to evaluate the SDP-exposure related effects on freshwater fish at the maximum approved open-water label concentration and exposure duration (100 mg/L for 8 hours) and using the expected lentic application technique (static application) are warranted. The variation in tolerance to P. fluorescens, strain CL145A, exposure observed in this study indicates that fish species community composition should be considered before SDP is applied in open-water environments.