TASK FORCE REPORTS
The Commission has established Task Forces to recommend direction and coordinate actions in several focus areas: St. Marys River Control, Sterile Male Release Technique, Barriers, Assessment, and Lampricide Control. The progress and major actions of the Task Forces for 1996 are outlined below.
ST. MARYS RIVER CONTROL TASK FORCE
I. Control Options
A. Reduce Reproduction
1&2. Trapping of spawning-phase sea lampreys and release of sterilized males
These ongoing activities are reported in the assessment spawning-phase and sterile male release technique sections of this report.
3. Enhanced adult trap at the Great Lakes Power facility
The new trap was installed in phases. First, the trap was suspended from the bridge wall. The device was positioned to function as a passive trap, although it was not designed for this application. Two weeks of fishing produced no lampreys. The electrical installation then was finalized and the pumps for the water attractant were activated on July 5. During this phase sea lampreys were first observed in the trap, but catches were much lower than expected. The last phase, connection of the pipe between the trap and a holding tank in the nearby hatchery, began July 26, but no animals swam from the trap, through the pipeline, to the hatchery tank, perhaps due to the lateness in the season.
Modifications to this trapping system will be incorporated before the 1997 season. The proposed changes are designed to attract more adults into the trap, and to entice lampreys to swim through the pipe to the hatchery.
4. Enhanced adult traps at United States Army Corps of Engineers facility
Construction of these traps may be delayed due to Corps administration restrictions, but the Task Force recommends construction of the new traps in 1997, even if completion is too late for the spawning run. The Commission portion of the construction total ($42,000) was committed in 1996.
B. Reduce Larval Population
1. Section Bayluscide treatments
With the successful aerial applications of granular Bayluscide to large plots (3.25 hectares) in 1996 (see Information Needs section), most questions of efficacy and logistics of this option have been answered. No areas will be treated in 1997, but the Task Force will make recommendations on the scale of future treatments.
2&3. Section and whole-river TFM treatments
The Task Force will analyze the results of the dye study and the TFM transport model, coupled with larval distribution maps, before making a recommendation on this option. Scenarios for treatment of the north channel must be analyzed for costs and effectiveness before a treatment can occur. The timeline shows 1998 as the earliest a TFM treatment could occur.
II. Information Needs
1. Larval and habitat mapping
A pilot study was successfully completed in 1992 which determined the feasibility of using a deepwater electroshocker and global positioning system equipment to take spatially referenced samples of the larval sea lamprey population in the St. Marys River and to map larval population density. This information is critical for planning and predicting the effectiveness and costs of treatment. The system incorporates geographically-referenced data on larval population density and data pertinent to predicting treatment effectiveness in a Geographical Information System database. At the direction of the Commission funds were reprogrammed for 1993-96 and work continued in 1996 to complete this multi-year task.
Table 23. St. Marys River Control Strategy - Timeline/Cost Estimates
Sampling Results for 1996
Two areas were sampled in 1996:
A total of 68.30 km2 have been surveyed since 1993 (Fig. 10) including 12.27 km2 examined in 1996.
Currently, maps and estimates of the larval sea lamprey population sampled in 1996 are being made.
Generally, results indicate sea lamprey larvae are even less concentrated in the Neebish Channel than in lower Lake Nicolet. Small concentrations of sea lampreys were found near Hen and Chicks islands, but no other concentrations of larvae were identified.
The larval mapping project for the St. Marys River is complete. All known, significant, infested areas have been surveyed. An estimate of total stock abundance will be made upon completion of gear efficiency studies and analysis. Larval distribution and densities will be used to make recommendations on control options for the St. Marys River.
1. Larval Density and Lampricide Treatment Scenario Model
A proposal to develop a software interface between outputs of larval sea lamprey densities and treatment scenarios generated by the flow model was submitted to and accepted by the Environmental Management Technology Center, U.S. Geological Survey, Biological Resources Division, LaCrosse, Wisconsin. Completion and trials of the software interface are expected by June 1997. The interface will allow examination of effects of lampricide treatment scenarios on the larval sea lamprey population in the St. Marys River.
2. Index of larval abundance
Index sites were established to provide background information necessary to evaluate control operations. A total of 13 index sites were sampled in 1996. Four areas in lower Lake Nicolet and near Squirrel Island were added to those index sites sampled in 1994 and 1995.
3. Aging/transformation rates
A total of 88 recently-metamorphosed sea lampreys were collected from the St. Marys River in 1995 and 1996. These were weighed, measured, and dissected to determine sex and to remove statoliths for age determination.
Fig. 10. Area surveyed
to determine distribution and abundance of sea lamprey larvae in the St.
Marys River, 1993-96.
Ages were assigned to each individual with an average error of 4.10 percent, with discrepancies in age not varying by more than one year. Age at transformation appears to be between 4 and 5 years (mean 4.95) which concurs with previous information suggesting large larvae (>120 mm) in the St. Marys River were predominantly 3 or 4 years old. Forty-nine (55.7 percent) of the lampreys were male, with no significant difference in age or size at metamorphosis between males and females.
4. TFM Transport Model
The contracted computer flow model for predicting TFM transport under varying discharge and application scenarios was further refined in 1996. Results of the rhodamine dye study (below) and water velocity measurements collected by the Corps with Doppler sonar were used to refine and calibrate the model. The Task Force will utilize the refined model in conjunction with the larval mapping information to choose and recommend the most cost effective use of TFM to control larval sea lampreys in the north channel.
5. Dye Study
The rhodamine dye study was conducted to validate and calibrate the TFM transport model and to provide empirical data for exploring the feasibility of a lampricide treatment. The model predicted that a treatment of the north channel might be effective with a single-point application of lampricide through the Great Lakes Power (GLP) generating facility. The model also indicated that an effective treatment of the south channel (Lake Nicolet) is not economically feasible.
The Wisconsin Central Railway trestle upstream of the GLP facility was selected as the dye application point (Fig. 11). The plant turbines provided effective mixing of the dye. Thirteen transects were selected downstream of the GLP for sampling to measure concentrations of dye in the block. A sampling protocol was developed incorporating Global Positioning System coordinates to locate sample sites.
The study was conducted on August 10-11, 1996. The total river discharge requested for the study was 1,700 cubic meters/second (cms), which is close to treaty minimum and a realistic discharge for treatment. However, due to the high level of Lake Superior and the inability of some hydroelectric companies to reduce flows during the study, total discharge was 2,180 cms. Discharge at the application point averaged 1,020 cms with the remainder of the flow split between the compensating works (100 cms), the Corps hydroelectric facility (310 cms), the locks operations (10 cms), and Soo Edison hydroelectric facility (730 cms).
Department personnel applied 413 liters of dye in 14 hours at a target concentration of 8 mgl-1 (total product). The dye was well mixed immediately downstream of the GLP. A total of 2,400 water samples were collected to monitor movement of the dye block during a 2-day period.
Results of the sampling were plotted with areas that achieved more than two-thirds of the application concentration for 9 hours considered effectively treated. The results indicate that a lampricide treatment, under similar flow conditions, would be effective only downstream to Little Lake George. Effective treatment of the entire north channel would require a longer application and/or a different discharge regime.
Fig. 11. Map of St.
Marys River showing the rhodamine dye application point, transect lines,
and area of effective dye coverage during the dye study of August 10-11,
The dye study required 70 personnel and numerous boats to sample the study transects. Many cooperating agencies provided personnel and boats for the study including the U. S. Fish and Wildlife Service (Marquette Biological Station, Ludington Biological Station, Alpena Fishery Resources Office, Lansing Ecological Services Office, Jordan River National Fish Hatchery, and Pendills Creek National Fish Hatchery), Department of Fisheries and Oceans (Sea Lamprey Control Centre and Great Lakes Laboratory for Aquatic Science), National Biological Service (Upper Mississippi Science Center and Lake Huron Biological Station), Great Lakes Fishery Commission, Michigan Department of Natural Resources, and the Chippewa-Ottawa Treaty Fishery Management Authority (COTFMA).
6. Section Bayluscide studies
At the direction of the SMRCTF, populations of sea lampreys and nontarget organisms were assessed in six 3.25-hectare plots in the St. Marys River in 1996. The plots were located in Lake Nicolet (four plots) and in the turning basin in the St. Marys River (two plots). A new bottom release formulation of Bayluscide was applied at 175 kg/hectare (5 lbs. active ingredient/acre) by a commercial pesticide applicator with a helicopter on July 12 and September 9. Applications were split between the two dates to allow assessment of the efficacy of the granular formulation of Bayluscide at two water temperatures (14 and 18o C). Post-application assessments were conducted to determine the effects on the populations of lampreys and nontarget species.
Deep-water electroshockers (DWS) were used to sample live larval sea lampreys and nontarget organisms on the stream bottom. Long-handled dip nets were used to collect lampreys and nontarget organisms at the surface. A minimum of one boat was assigned to each plot with a second boat assisting periodically in collection efforts. An underwater video camera, mounted on a remotely operated vehicle, recorded dead lampreys and nontarget organisms observed on the bottom.
Pre-assessment surveys were conducted by DWS before the application of Bayluscide to determine the density of larval sea lampreys. Post-assessment surveys were conducted by DWS, dip net, and underwater video camera after the application to assess the effectiveness of the Bayluscide formulation.
A total of 3,396 kg of granular Bayluscide formulation was applied with each plot receiving 566 kg. The Bayluscide granules appeared to be well targeted and evenly spread.
A total of 578 larval sea lampreys and 2,719 nontarget organisms were collected by DWS. The nontarget organisms represented 9 taxa of macroinvertebrates and 5 genera of fishes.
Live animals collected by DWS included 195 sea lampreys and 6,316 nontarget organisms. The organisms again represented 9 taxa of macroinvertebrates and 5 genera of fishes. An additional 1,073 sea lampreys and 53 nontarget organisms were collected during 15.45 boat collection hours. Thirty-two dead lampreys and 17 dead nontarget organisms were seen during 7.2 hours of observation with the underwater video camera.
7. Bayluscide efficacy testing (lab studies)
Laboratory studies on Bayluscide efficacy were completed early in 1996 and summarized in the 1995 annual report.
8. Stock-recruitment workshop
A compensatory mechanisms workshop was held on April 10-11, 1996, in Ann Arbor, Michigan. The data presented suggests that density dependent changes in growth and mortality occur at low densities. Low spawning stocks appear to be capable of reproducing the population of parasitic lampreys.
III. Environmental Assessment
1. Public information/input
The Task Force recommends the initiation of public meetings beginning in 1997 to provide information and to gain public/agency support for the St. Marys River control initiatives.
2. Nontarget impacts
The Task Force recognizes the need to obtain more information on potential impacts on nontarget organisms, particularly when using spot applications of the granular formulation of Bayluscide. It recommends bottom trawling to assess populations of nontarget species in potential treatment zones. Assistance from other agencies is being solicited to conduct these studies in 1997.
STERILE MALE RELEASE TECHNIQUE TASK FORCE
Strategic Long-term Integrated Management of Sea Lamprey (IMSL) Planning
1. Are male sea lampreys successfully sterilized?
2. Do sterilized males reach the spawning grounds and construct nests at the expected ratio of sterilized to resident males?
3. Do sterilized males attract females to nests and mate normally?
4. Does sterility persist through mating and is percent survival of embryos at hatch reduced in individual nests?
5. Is percent survival of embryos at hatch reduced in individual streams?
6. Is the abundance of year classes of burrowed larvae (after leaving the nest) reduced in individual streams?
7. Do reductions in abundance of larvae persist through the larval life stage and result in reductions in the number of metamorphosing sea lampreys in individual streams?
8. Is the number of parasitic-phase sea lampreys in the lake reduced?
9. Is damage to fish in the lake reduced?
SEA LAMPREY BARRIER TASK FORCE
Barrier Projects and Related Work Proposed and Accepted for FY 1997:
ASSESSMENT TASK FORCE
LAMPRICIDE CONTROL TASK FORCE
Riffle community index
Index areas of macroinvertebrate riffle communities were established in the Brule (Lake Superior) and West Branch of the Whitefish (Lake Michigan) rivers in 1985 and Sturgeon (Lake Huron) River in 1986. Sampling of macroinvertebrate populations in these areas was designed to assess long-term effects of applications of TFM. The design followed a strategy developed by the Environmental Effects of Lampricide Committee in 1983.
Samples were collected by standard traveling kick method in the spring and fall, before and after lampricide treatments in the Brule and Whitefish rivers (1986, 1989, and 1992) and in the Sturgeon River (1988 and 1994). Samples were taken upstream (control) and downstream (treated) of lamprey barriers in the Brule and Whitefish rivers. Samples were collected from a treated site in the Sturgeon River, and a control site of similar stream morphology in the Boardman River (Lake Michigan). Collection of specimens concluded in the Brule and Whitefish rivers in 1993 and in the Sturgeon and Boardman rivers in 1995.
Macroinvertebrates were identified to genera with the exception of early instars which were identified to higher taxonomic levels. The numbers of macroinvertebrates were recorded and analyzed by nested ANOVA procedure. Comparisons were conducted on total number of macroinvertebrates, number of taxa, and total number of organisms in taxa found in both control and treated sites in one or more of the streams. Comparisons were further classified by stream, year, and period of collection (spring during years of treatment, spring at least six months after treatment, and fall at least one year after treatment).
About 700,000 macroinvertebrates were collected which represented 183 taxa. A total of 670 statistical comparisons were conducted on macroinvertebrates of 127 taxa found in both control and treated index areas. The total number of organisms, number of taxa, or number of organisms within each taxa were similar or significantly greater in treated areas in 94 percent of the comparisons. The number and taxa of organisms collected varied among years and seasons but followed similar trends in treated and control sites in the rivers. The effect of applications of TFM on macroinvertebrate communities was minimal compared to the effect caused by natural environmental factors. The findings will be detailed in a project completion report.
Lake Sturgeon studies:
Protection of lake sturgeons (Acipenser fulvescens) during sea lamprey management activities is a priority. In 1982 the lake sturgeon was being considered for threatened or endangered status, and was listed in the federal Notices of Review Register as a category 2 (C2) candidate species. In 1995 the C2 classification was removed and the lake sturgeon now has no formal designation. Streams in which the safety of lake sturgeons may be a concern include the Sturgeon and Bad rivers (Lake Superior) and Peshtigo River (Lake Michigan).
A collaborative biotelemetry study of the migration of lake sturgeons and walleyes (Stizostedion vitreum) was conducted in the Bad River. The objective of the study was to determine if lake sturgeons and walleyes migrate upstream of two low gradient water falls and the Elm Hoist Road crossing, a potential site for a sea lamprey barrier. Participants included personnel from the Fishery Resources Office in Ashland, Wisconsin, U. S. Geological Survey Biological Resources Division Lake Superior Biological Station, Bad River Band of Lake Superior Chippewa Indians Natural Resources Department, Great Lakes Indian Fish and Wildlife Commission, Department of Fisheries and Oceans Canada, and Marquette Biological Station. Biotelemetry tags were attached to nine walleyes captured in gill nets in the lower river and one lake sturgeon taken upstream from Elm Hoist Road. None of the walleyes tagged and released near the stream mouth moved upstream as far as the potential barrier site. A single lake sturgeon captured and released upstream of Elm Hoist Road emigrated from the stream after release.
Personnel from Michigan Technological University in Houghton, Michigan, and Marquette Biological Station monitored the downstream movement of lake sturgeon fry in the Sturgeon River in Baraga County, Michigan, between May 29 and June 14. A total of 265 migrating lake sturgeon fry were captured and released.
In a cooperative study, personnel from the Upper Mississippi Science Center, LaCrosse, Wisconsin, the Bad River Band of Lake Superior Chippewa Indians Natural Resources Department, and Marquette Biological Station conducted flow-through toxicity tests with TFM on juvenile and adult freshwater mussels. Atlantic elliptios (Elliptio complanata) and floaters (Anodonta cataracta) were exposed to TFM in water from the White River, a tributary of the Bad River, Ashland County, Wisconsin. The mussels along with sea lamprey larvae were exposed in each of 3 tests to a range of 9 concentrations of TFM for 12 hours.
In the 3 tests, 98.6 percent (853 of 865) of the mussels exposed to TFM survived. All mortalities occurred in concentrations of TFM greater than those used for treatment under similar water chemistry conditions (1.9 to 2.5 times the LC99.9 for sea lamprey larvae).
Behavioral responses, including valve gaping and foot extension, also were monitored. No responses which increase the exposure of the organisms to predation were observed at the LC99.9 of sea lamprey. A one-year post exposure assessment of mussels from three tests will measure latent mortality and growth among the treatment groups.
Onsite flow-through toxicity tests were conducted with whitefish (Coregonus clupeaformis) at the COFTMA fish hatchery on Nunns Creek in Mackinac County, Michigan. Whitefish were more sensitive to TFM than brown trout (Salmo trutta), but less sensitive than sea lamprey larvae in 12-hour exposures under similar water chemistry conditions. The 12-hour LC50 for brown trout (6.80 mgl-1 TFM) is about 1.7 times that of whitefish (3.95 mgl-1 TFM). The 12-hour empirical LC0.1 for whitefish (2.8 mgl-1 TFM) was about two times the 9-hour LC99.9 for sea lamprey larvae (1.5 mgl-1 TFM).
The Service and Department routinely are involved in outreach activities to inform the public of the benefits and operations of the sea lamprey management program. These activities range from major group participation at sports shows in metropolitan areas to the efforts of individuals in the many contacts with the media and presentations at schools. A summary of these activities for 1996 follows. (Table 26)
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