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Ohio River Black Bass

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Ohio River Black Bass2002 Status Report

Largemouth Bass

Smallmouth Bass

Spotted Bass

Ohio River Fisheries Management Team

EXECUTIVE SUMMARYThe Ohio River Fisheries Management Team continued to monitor and manage Ohio River black bass populations, habitats, and fisheries through a coordinated sampling effort in 2002. Results provide a river-wide perspective of these important sport fishes. Key activities and findings include the following: SAMPLING. ORFMT states are collectively monitoring black bass populations in five study pools throughout the Ohio River. SPECIES COMPOSITION. Habitat is better suited for smallmouth bass in the upper Ohio River, while downstream areas are better suited for spotted and largemouth bass. ABUNDANCE. Smallmouth bass catch rates are greater in the upper river, whereas spotted and largemouth bass catch rates are greater in the lower river. These trends are more apparent in 2002. GROWTH. Growth is similar among pools in 2001 and 2002. Smithland Pool black bass grow as fast as Hannibal Pool black bass. Ohio River black bass continue to grow fast, reaching 12 inches or greater in three growing seasons. REPRODUCTION. Results suggest that reproduction and survival of young fish spawned in 2001 was greater that those spawned in 2000. CONDITION. Health of Ohio River black bass is similar to last year. Fish are in excellent condition, indicating that a good supply of food is available. TOURNAMENT RESULTS. Tournament catch rates (number of 12 inch bass caught per hour of fishing) tended to increase from lower to upper portions of the river. STOCKING. WVDNR stocked largemouth bass in 2002. Results from this pilot study are pending, update will be available in 2003. HABITAT MONITORING. ODNR continues pilot study to evaluate the effects of varying flows and temperatures on reproduction and survival in the Belleville Pool. Results are still preliminary and will be reported on more fully in future reports. HABITAT IMPROVEMENT. KDFWR initiated development of a pilot project to evaluate artificial structure on spawning in the Meldahl Pool. PARTNERSHIPS. The ORFMT has participated in several meetings with the U.S. Army Corps of Engineers to discuss Ohio River issues related to access, dredging, and navigation. CREEL SURVEY. Tailwater surveys were initiated in Fall 2001. Summaries of angler catch rates, harvest, and effort are pending, update will be available in 2003. ACCESS. The ORFMT states continue to add and renovate access sites throughout the Ohio River to increase fishing opportunities.

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INTRODUCTION & BACKGROUNDBlack bass (largemouth, smallmouth, and spotted bass) are important Ohio River sport fishes. They provide boat- and shore-fishing opportunities from all areas of the river, making bass fishing an important recreational activity on the river and a valued source of revenue for the regional economy. Historically, annual angling success for black bass on the Ohio River has been variable. These fluctuations are likely due to changes in water temperature, water level, and availability of food. To better manage this fishery, the states bordering the Ohio River have been working collectively to identify the factors which regulate reproduction and survival. The border states formed the Ohio River Fisheries Management Team (ORFMT; Figure 1) in 1990 in response to a U.S. Supreme Court ruling on multi-state ownership of the river. Since that time, the ORFMT has pursued cooperative interstate fisheries management throughout the river.

IL

PA IN OH WV KY

In the Fall of 2001, the ORFMT began Figure 1. Ohio River Fisheries Management Team states. monitoring black bass populations river-wide. A summary of these activities is provided in this ORFMT update. Data are compared with largemouth bass averages from Ohio River monitoring in 2001.

ACHIEVEMENTS, 2002 Monitored black bass populations in five pools to determine population quality. Monitored temperature and water level fluctuations in Belleville Pool to evaluate their effects on reproduction. Conducted angler surveys in eight tailwaters to evaluate sizes and numbers of fish caught. Summarized tournament data reporting to monitor bass populations. Continued evaluation of largemouth bass stocking in Belleville Pool. Met with U.S. Army Corps of Engineers to improve fishing opportunities. Presented project updates to bass angling organizations.

STUDY AREA

PA IN2 4 3

IL

OH

1STUDY POOLS1 - Hannibal

N

2 - Belleville 3 - Meldahl 4 - Cannelton 5 - Smithland

5 Ohio River

WV

KY

Figure 2. Study pool locations.

Black bass were sampled with shoreline electrofishing from the five study pools in Fall 2002 (Figure 2). Bass were identified, measured, weighed, and aged. Abundance was estimated by catch per effort of all sizes of bass. Average length at each age was determined to estimate growth. Bass health was examined by relating lengths and weights of individual fish to estimate body condition. Reproductive success was determined by relative percentage of age 1 fish present in electrofishing samples. Results were compared with 2001 data.

SPECIES COMPOSITION

IL

IN OH

PA

Belleville Cannelton

Hannibal

WVN

Smithland

KY

Meldahl

Largemouth Smallmouth Spotted

Figure 3. Composition of black bass species from the mouth to the headwaters of the Ohio River.

Habitat changes from the headwaters to the mouth of the Ohio River. These changes, including temperature, gradient, flow, substrate, and backwater areas influence species composition. Habitat in the upper Ohio River is more suitable for smallmouth bass; whereas, downstream habitat is better suited for spotted bass.

ABUNDANCE100 80 60

2001

Largemouth Smallmouth Spotted

30

Total Catch / Hour of Electrofishing

20

10

0

100 80 60

2002

30

20

10

0

Hannibal

Belleville

Meldahl

Cannelton

Smithland

Figure 4. Ohio River black bass catch rates per hour of electrofishing from each of the five study pools, 2001-2002.

Standardized sampling began in 2001. Largemouth and spotted bass catch rates are seemingly random in the first year of sampling; however, catch rates in 2002 are directly related to upstream and downstream habitat. Smallmouth bass catch rates are higher in the upper river pools, whereas spotted bass and largemouth bass catch rates are higher in the lower river pools.

GROWTH

14 12 10 8 6 4 2 0 2001 2002

L a rg e m o u th

12 Inches by age 2!

S m a llm o u th14 12

Length (inches)

10 8 6 4 2 0

Legal Size

S p o tte d14 12 10 8 6 4 2 0 0 1 2 3 4

AgeFigure 5. Average lengths at age of Ohio River black bass.

Length-at-age data were combined for all of the study pools because there were no differences in growth among pools in 2001 and 2002. Smithland Pool black bass grow as fast as Hannibal Pool black bass. All three species reach 12 inches during their third growing year, indicating that the fishery is made up of fast-growing fish ages 2 and older.

Reproduction6

Upper5

2001 2002

Total Catch per Hour of Electrofishing (Age 1)

4 3 2 1 0 6 5 4 3 2 1 0Largemouth Smallmouth Spotted

Lower

Figure 6. Ohio River catch rates per hour of electrofishing of age-1 black bass from the upper (Hannibal and Belleville Pool) and lower (Meldahl, Cannelton, and Smithland Pools) study pools, 2001-2002.

Small fish grow to become large fish. In an effort to predict numbers of fish entering the fishery, we are monitoring numbers of young fish. Based on our length-at-age data, these fish will enter the fishery within the next two years. Pools with similar habitat were grouped into an upper region (Hannibal and Belleville Pools) and a lower region (Meldahl, Cannelton, and Smithland Pools) to improve sampling accuracy. Results suggest that reproduction and survival of young fish spawned in 2001 was greater than those spawned in 2000.

CONDITION

Body condition is a measure of fish health. Condition in 2002 is similar to that in 2001. Ohio River black bass are in good to excellent condition, indicating that there is a good supply of food available.

EXCELLENT GREAT GOOD FAIR

2001 2002

Largemouth

Smallmouth

Spotted

Figure 7. Condition of Ohio River black bass from all pools combined, 2001 and 2002.

Excellent Condition

Fair Condition

TOURNAMENT RESULTSIn 1999, the ORFMT began collecting standardized black bass tournament data river-wide. This allowed states to evaluate the success of competitive angling and track populations. Results are reported as the number of hours it took to catch a 12-inch largemouth bass, smallmouth bass, or spotted bass. Species composition is not uniform throughout the 981-mile length of the Ohio River. To allow for a river-wide evaluation, the Ohio River was divided into four sections. 1 3 2

4

Lock and Dam

River Sections1. 2. 3. 4. New Cumberland Pool - Hannibal Pool Willow Island Pool - Racine Pool R.C. Byrd Pool - Markland Pool McAlpine Pool - Smithland Pool

Figure 8. Ohio River sections used for analyzing black bass tournament data.

Tournament hours needed to catch a 12 inch black bass increased from the upper to the lower portion of the river. Catch rates for the entire river spiked in 2001 due to the differences in section 2 catch rates. These rates returned to levels of previous years in 2002 which decreased the overall river results. This spike may be attributed to a higher numb

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