PRODUCING A TROPHY LARGEMOUTH BASS FISHERY (CASE STUDY) Greg Grimes President of Aquatic Environmental Services, Inc.
Background 32 acre lake in Harris County, Georgia o The construction of the lake began in 2007 and was completed in 2008. Primary objective for the lake: ocreate an outstanding trophy largemouth bass fishery. Management Discussed o Lake design and construction o Water quality ofish Stocking Protocol o Feeding program obass Harvest
Design and Construction In developing fish habitat, we had three primary objectives: 1. Spawning Areas 2. Protective/dense cover for forage fish 3. Larger/Deeper material for orientation/ambush points
Spawning Areas Spawning Flats 1. Smoothed flat areas in 2-4 in water depth near shore. 2. After grading, flats were covered with pea gravel to create ideal spawning areas
Spawning Areas Spawning Tables 1. Spawning tables were created out from the shoreline 2. Used existing roads from construction and by building up underwater points 3. Spawning tables were built in 3-4 feet water depths and additional tables in 4-7 feet depths for drought conditions
Dense/Protective Cover Dense/Protective Cover 1. Dense material placed in key areas to provide protective cover, increasing recruitment of small fish. 2. Majority of dense material placed on perimeter of spawning areas.
Dense/Protective Cover Natural material was important to create protective habitat for small fish: 1. Cedar Trees 2. Tree Tops 3. Root Balls 4. Rock Piles
Orientation/Ambush Points Large structure items provide orientation and ambush points for largemouth bass Used large materials (i.e. tree trunks) and placed around reshaped lake bottom 1. Points 2. Drop Offs 3. Ridges 4. Humps
Bathymetric Map
Water Quality (Lime Application) Majority of waters in Georgia: 1. Poor soils 2. Low alkalinity levels Lake was limed with 6 tons of agricultural lime per acre. 1. Raises alkalinity level 2. Environment for Successful fertilization 3. We actually repeated this in 9 months
Water Quality (Fertilization) Fertilized to maintain a visibility of 18-24 Goals is to maximize the food chain 1. Strong Phytoplankton bloom 2. Results were 24-36 most times. 3. Had growth of good phyto vs. cyanobacteria
Water Quality (Bottom Diffused Aeration System) Bottom Diffused Aeration System 1. Protects all of our hard work 2. Prevents stratification and increases fish habitat 3. Provides sufficient oxygen levels throughout the water column 4. Long-term muck reduction in the lake
Supplemental Feeding Program 13 automatic fish feeders on 32 acres of water 1. Feeding schedules adjusted throughout the year 2. During growing season feeders were set for four times a day 3. Approximately 75 pounds of food per month= 5 tons/year 4. Used a high quality fish food 42% Protein 12% Fat ¼ Floating Pellet
Fish Stocking Lake stocked at 44:1 compared to usual 10:1 March 2009: bluegill, redear sunfish, fathead minnows and grass carp April 2009: threadfin shad, golden shiners and crayfish June 2009: bass July 2009: hybrid striped bass Species Coppernose Bluegill Size Per Acre Rate Total 1-2 2,000 62,000 Redear Sunfish 1-2 200 6,200 Fathead Minnows Adults 2,000 62,000 Threadfin Shad Adults - 2 Loads (8,000) Golden Shiner Fry Fry 100,000 Three Million Crayfish - 40 lbs. 1,240 lbs. Grass Carp 8-10 1 31 August 2009: advanced largemouth bass Largemouth Bass (Florida, Northern, F1) Largemouth Bass (Advanced F1 s) Hybrid Striped Bass 2 40 1,240 3-4 10 310 1-2 10 310
Fish Stocking Rainbow Trout 1. Stocked 3,000 (5-7 ) Rainbow Trout in the Fall of 2010 Gizzard Shad 1. Stocked in Fall of 2011
First Electrofishing survey conducted on April 1 st 2010 Of Bass Sampled Average Length: 15.6 Average Length: 2.48 lbs. Average Relative Weight: 115% Results
Electrofished again in November 2010 Of Bass Sampled Average Length: 15.4 Average Length: 2.5 lbs. Average Relative Weight: 114% Largest Bass Sampled Length 18 Weight 4.8 lbs. Wr 147% Results
March 3 rd, 2011 Biggest bass was actually caught- Jeff catches a five pound bass Electrofished on April 25 th, 2011 Average Relative Weight: 112% One 17 Hybrid Striped Bass sampled Results
October 18 th, 2011 Of Bass Sampled Average Length: 16.3 Average Length: 2.83 lbs. Average Relative Weight: 102% Results
Results October 18 th, 2011 Largest Bass Length: 21.0 Weight: 7.5 lbs. Wr: 143%
February 2012 Exceptional day of fishing where four bass over six pounds were caught in four consecutive casts This big boy was 7.7 lbs. Results
March 2012 Largest Bass was 6.9 lbs. Results
Caught after electrofishing survey in March, 2012 8.4 lbs. Results
Hybrid Striped Bass growing well >3 lbs. Results
Lake Record >8 lbs. in less than three years Not Known Current Sizes? Results
Weight (lbs.) 9 8 7 6 Size of Largest Bass Compared to Known bass weights of standard stocked pond. Case Study Standard Rate Mar-12, 8.4 Oct-11, 7.5 5 Nov-10, 4.8 Mar-11, 5.0 4 3 2 1 0 Jun-09, 0 Jun-09, 0 Apr-10, 2.48 Sep-10, 1.8 Mar-10, 1.2 Apr-11, 1.8 Nov-11, 2.8 Mar-12, 3.9 Month and Year
DNA Testing Fin clips from five of the largest bass sampled were sent to Auburn University for testing. Four of the bass were Dominant Northern Hybrid, and one was a Pure Northern Dominant Northern Hybrid 4/5 informative alleles are from a Northern Background Hard to explain when these were not stocked.
Bass Harvest Bass (pictured) collected in first electrofishing survey in April 2010 Bass on right did not make the cut Bass on the left: 138% Relative Weight Bass on the right: 105% relative weight
Continued Management On course for bass to weigh in the double digits but our work is not done Additional lime applications necessary every three years to maintain alkalinity levels Fertilizer applications maintained. Check visibility every two weeks during growing season o 2011 applied Urea, lake was nitrogen limited- continue monitoring water chemistry Adjust and fill feeders on monthly basis during growing season Adding protective habitat as the current habitat decomposes o Dense cover required to protect and increase small bluegill abundance Reach harvesting goals each year o 2012 Goal 1,000 pounds to maintain desired balance
Key Points Big Bass and Rapid Growth = Stocking more forage and less bass Design Lake for Habitat of stocked species Follow BMP of pond management and never let up the culling of skinner bass
Further Studies Bass Genetics- what subspecies for best startup growth and long-term top end? How to maximize fertility- testing N:P vs. visibility? Or identification of plankton? Fish food quality to match fish species- best food for bluegill Habitat Longevity and Evaluation- Natural vs. Manmade
THANK YOU QUESTIONS?