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2000 First Quarter Report
Ohio River Largemouth Bass Studies:
Task 2: Juvenile Habitat Use and Movements
Submitted to:
West Virginia Department of Natural Resources
Division of Wildlife
Submitted by:
Jason G. Freund and Kyle J. Hartman
West Virginia University
College of Agriculture, Forestry, and Consumer Sciences
Division of Forestry
Department of Wildlife and Fisheries
322 Percival Hall, Box 6125
Morgantown WV 26506-6125
(304) 293-2941
Assessment of YOY and juvenile largemouth bass habitat use in the Belleville and Willow Island pools of the Ohio
River continued through the first quarter of 2000. The information presented in this report is for data collected
between January 1 and March 31, 2000.
Objectives
- Determine young-of-year (YOY) and juvenile largemouth bass habitat selection within the Belleville and Willow
Island pools of the Ohio River.
- Determine seasonal water quality differences between various habitat types (mainstem, embayment, tributary),
and correlate water quality differences with YOY and juvenile bass habitat preferences.
Telemetry Methods
Tracking of fish tagged with Advanced Telemetry Systems (ATS) radio transmitters continued in the first
quarter of 2000. Using a receiver and hand-held loop antenna, fish previously implanted with radio transmitters
were located by searching for the radio frequency specific to that radio transmitter. Once the signal for a specific
radio tag was audible, fish position was recorded by taking compass readings at three locations. Also recorded
at each of the three locations were GPS position, date, and time. At the third triangulation point water quality
and habitat measurements were also taken including: temperature, current velocity, dissolved oxygen, turbidity,
conductivity, salinity, and visible habitat type.
Electrofishing Methods
The embayment macrohabitat type was surveyed using boat electrofishing in French creek within the Willow
Island pool. Due to equipment and weather-related problems this was the only habitat we were able to sample during
the first quarter. Field sampling occurred during daylight hours in the first quarter.
All fish were collected by direct current (DC) pulse boat electrofishing. Surveys were conducted at a constant
speed for 15 minutes along littoral zones within the habitat type. In an effort to cover as much area as possible
during surveys, only bass were netted. At the completion of every electrofishing survey all fish captured were
counted, and total lengths were recorded. In addition, all YOY and juvenile bass of appropriate weight (over 62
grams) were tagged with a radio transmitter. We collected microhabitat utilization data by placing a buoy at the
approximate capture site for each YOY or juvenile largemouth bass. Upon completion of fish processing we returned
to the buoy sites to measure water quality and habitat parameters. At each marker buoy the GPS position and time
were recorded as well as water temperature, dissolved oxygen, turbidity, depth, conductivity, salinity, nearest
habitat feature, and visible habitat type.
All YOY or juvenile bass exceeding 62 grams were held for radio tag implantation. After being anesthetized in a
clove oil solution, fish were tagged with an ATS radio transmitter of a specific frequency. A small incision was
made slightly anterior and dorsal to the anal vent to allow insertion of the transmitter, and an exit opening for
the antenna was made with a straight needle, and several sutures were made to seal the opening. Fish were recovered
in an aerated tank until equilibrium and swimming ability were regained. After recovery, all fish were released
near their capture site.
Telemetry Progress to Date
During electrofishing surveys in the first quarter, six juvenile bass were captured and implanted with
radio transmitters. This increases our total sample size of radio tagged fish to 30. We were only able to spend
two days searching for the radio tagged YOY and juvenile bass during the first quarter of 2000 due to the limited
ability to capture bass to tag during electrofishing surveys. Due to the short battery life of the radio tags,
none from the previous quarter were still active. Tracking efforts within French creek and along the adjacent main
channel shoreline located four of the six tagged fish. Each of these fish were located only once, despite the tracking
surveys being spaced only three days apart. This suggests the juveniles may have moved out into the main channel.
While tracking surveys of the adjacent main channel did not locate any of the tagged fish, the greater main channel
depth may have prevented us from picking up a signal. It is also possible the tagged fish may have moved back into
extremely shallow water in the back of the embayment. Because of the distance, the antenna may not pick up a signal
from tagged fish in the very back of the embayment. Due to low water conditions during the end of the first quarter,
we were unable to get the track boat back into this area. Juvenile bass macrohabitat locations for 1998 through
the first quarter of 2000 are given in Figure 6. Based upon the telemetry distribution data, the preferred macrohabitat
type appears to be embayment areas. Radio tagged juvenile bass were located 61 times in embayment habitats, which
is more than twice the number of locations for tributary habitats. To date, only one tagged fish has been located
in the main channel and this was on a single occasion. The six radio transmitters implanted in bass this quarter
should still be active, and tracking surveys for these fish are continuing into the second quarter. We have also
purchased additional tags to implant during the 2nd quarter of 2000.
Electrofishing Progress to Date
A total of two field days and 2.25 hours (135 minutes) were spent electrofishing for YOY and juvenile
bass in the French creek location within the Willow Island pool for habitat use assessment during the 1st quarter
of 2000. Our electrofishing catch per unit effort (CPUE) for the first quarter was eight fish per hour, for all
sizes of YOY and juvenile bass. Based on the good catch rates in French creek last fall, electrofishing effort
was focused in this location. Our CPUE results in the Belleville and Willow Island pools for the three combined
macrohabitats in 1998 and 1999 are given in figure 7. As the graph shows, the addition of the French Creek location
in the Willow Island pool has significantly improved out catch rates. Despite the limited electrofishing effort
for the first quarter, our CPUE in French Creek has remained higher than our overall catch rates from the Belleville
pool for 1998 and 1999. We had hoped to reclaim some of the transmitters from fish previously tagged, and return
them to ATS for reconditioning. However, to date we have not recaptured any of the radio tagged bass.
In addition to field efforts in the first quarter, presentations of our findings to date were made at the Tri-state
AFS meeting in Lexington, VA and the Northeastern Fish and Wildlife Agencies conference in Charleston, WV.
Future Efforts
We will be continuing our efforts to collect YOY and juvenile bass to tag with radio transmitters in
the second quarter of 2000 within the Willow Island and Belleville pools. We still hope to recapture some bass
previously tagged. We have ordered 20 additional radio tags to be used for habitat use assessment. We also will
be conducting a diel tracking survey this spring to determine if there are any significant daily movements of the
YOY and juveniles among macro and microhabitat types.
In addition to the electrofishing and tracking surveys, we will be conducting a habitat availability survey. By
using shoreline transects we will be able to establish the amount of each habitat type that is available to bass
within both the Willow Island and Belleville pools, and identify if preferred habitats have limited availability.
Figure 6. Fish locations by macrohabitat type
during radio telemetry surveys from 1998 through the first quarter of 2000.
Figure 7. Total Annual Catch Per Unit Effort for
1998 and 1999 in the Belleville and Willow Island pools of the Ohio River.
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