1998 Fourth Quarter Progress Report

Evaluation of Largemouth Bass Stocking In Two Ohio River Embayments

Eric C. Janney & Kyle J. Hartman
West Virginia University
Division of Forestry
Wildlife and Fisheries Management
January 18, 1999

Objectives

1. Determine if stocking embayments can be used as a practical management tool to improve the Ohio River largemouth bass (Micropterus salmoides) fishery.
2. Determine the impact of stocking largemouth bass into a riverine system.
3. Determine whether stocked bass contribute significantly to the catch of largemouth bass by recreational and tournament anglers.

Study Area
French Creek (Willow Island Pool) and Little Mill Creek (Racine Pool) were selected as stocking sites by the West Virginia Department of Natural Resources and Dr. Kyle Hartman based upon size and potential largemouth bass habitat.

Methods
Pre-Stocking Assessment
Prior to stocking the embayments, a series of three boat electrofishing surveys were conducted at each study site during September and October of 1998. DC-pulsed electrofishing was conducted along the shoreline of each embayment and the main stem of the Ohio River in the vicinity of the embayments. A standardized unit (1 hr.) of effort was applied for each survey and the same areas were sampled on each date. This information will be used to provide baseline information on the bass community structure and species composition for each study area prior to stocking.

Stocking
On October 20, 1998 French Creek (118.8 acres) and Little Mill Creek (22.6 acres) were stocked with approximately 2671 small: 1111 large, and 666 small: 250 large largemouth bass, respectively. These stocking levels correspond to approximately 25 small (6 inches) and 10 large (10-12 inches) fish per acre of embayment. Prior to being stocked, each fish was weighed, measured, and tagged.Two tagging techniques were employed to help ensure we could later identify each fish. The fish were marked with a "Floy" anchor tag bearing a random number as well as a contact name and telephone number. Also, a fluorescent polymer was injected subcutaneously at the base of the anal fin of each fish. The polymer tag will be used in future electrofishing surveys to identify stocked fish that have lost their anchor tag.

Post handling mortality and tag retention
To get an indication of post-handling mortality and tag retention of stocked fish, 417 of the tagged hatchery fish were randomly selected and placed into 2 ponds at the Palestine State Fish Hatchery. Fathead minnows (Pimephales promelas) were placed into each pond to provide a food source for the bass. The ponds were drained on November 20, 1998 (31 days post-handling) and the fish were weighed and checked for tag retention. Relative condition of each bass was also recorded. The results of this study indicated that 250 (60%) bass survived one month in the hatchery ponds. The majority of fish mortalities (149) were unaccounted for. Only 22 bass carcasses were found after the ponds were drained. As personnel from the Palestine hatchery reported that herons and raccoons frequented the study ponds on a regular basis, mortality from predation may have been substantial. Therefore, the resulting survival rate seen in the hatchery ponds should be considered a conservative estimate of survival of tagged fish in the embayments. The fluorescent polymer exhibited a 98% retention rate in bass which survived in the study ponds one month. Floy tag retention was estimated to be close to 100% after one month.

Post-Stocking Surveys
Electrofishing surveys will be done on a monthly basis at each study site throughout the course of this project. Surveys are comprised of four 15-minute surveys along the shoreline of each embayment, and 15-minute surveys upstream and downstream of the embayment on the Ohio River. This information will be used to monitor the population structure of stocked bass vs. wild bass in each embayment. Before and after stocking comparisons will also be used to make inferences on the impact the stocked bass have on species composition and abundance of the embayments.Creel surveys will be conducted on a monthly basis throughout the course of the project. This will be used to determine the return of the stocked bass vs. wild bass to angler's creel. Also, signs explaining the project and encouraging anglers to report any tagged fish caught have been placed at access ramps, and sporting good stores in the vicinity of both study areas.

Progress
Electrofishing
Prior to stocking on October 20, each embayment was surveyed on three different occasions. A total of four 15-minute runs were completed along the shoreline of each embayment for each survey. Also, one 15-minute run was completed upstream and downstream on the main channel of the Ohio River outside of each embayment for each survey. Between the October 20, 1998 stocking date and December 31, 1998 each embayment has been surveyed on three occasions using the methods described above.

Creel Surveys
A creel survey protocol was established for this project using creel methods employed by the West Virginia DNR. A total of four creel surveys were completed at each study site between October 20, 1998 and December 31, 1998. A total of 14 tagged largemouth bass have been reported from Little Mill Creek during the four surveys. At French Creek, 17 tagged fish were reported during creel surveys. Another 25 tag numbers and locations have been reported to the Parkersburg DNR office. All of the tag numbers reported to the DNR office were caught from the Willow Island pool.

Special Considerations
A lack of publicity about the project has proved to be a major problem for collecting tag information from anglers. During fall creel surveys a large number of interviewed anglers did not record tag information and catch locations. A solution to this problem may be to provide voluntary creel cards to anglers. These cards would be available at local bait shops, marinas, and also at tournaments held in the Racine, and Willow Island pools. The tag numbers and catch locations would be recorded on the creel card and mailed by the angler at the end of each trip.