Catfish Inventory Losses

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Catfish Inventory Losses

• Gary J. Burtle
• Animal Dairy Science
• College of Agricultural Environmental Sciences
• University of Georgia

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You may be loosing catfish every day!

• Losses over the winter
• Losses due to chronic disease
• The effect of holding catfish over time

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Winter Losses

• Fungal diseases
• Winter Kill syndrome
• Parasites
• Poor nutrition
• Cannibalism

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Winter Loss Study

• Fingerlings alone VS Fingerlings on top of 1.5
  pound catfish
• 4,000 fingerlings /acre
• 1,000 pounds of 1.5 pound catfish per acre
• Stocked in late December
• Harvested in mid-March
• All ponds fed 1 of initial weight per day

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Percentage Over-winter Fingerling Losses ()
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Reasons for Over-winter Survival

• WITHOUT LARGE FISH
• No Cannibalism
• No Residual Disease

• WITH LARGE FISH
• Some Cannibalism
• Protozoan Parasites Carried by Large Fish
• Feed Competition

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Large Fish Survival Over-Winter(Weight, Grams
Survival, )
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Expected Over-Winter Losses(Average of Three
Ponds per Treatment)

• Fingerlings average 69.3 with large catfish
• Fingerlings average 76.2 without large catfish
• Best was 92.7 survival over the three month
  period
• Large catfish averaged 90.7

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Catfish Lost in the Growing Season (Common Causes)

• Acute Disease
• Chronic Disease
• Water Quality
• Harvest Injury
• Predator Activity
• Theft

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Catfish Losses Observed and Actual During Growing
Season(Losses at Start, Chronic or at End of
Season)
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First Year Harvest Pattern

• 7,500 per acre
• 1.5 pound harvest weight target
• Stocked in May
• Harvested August to November
• Catfish Graded and Returned if Too Small
• 9 ponds compared, 3 catfish only, 3 catfish and
  shad, 3 catfish and minnows

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Percent Harvested in First Year
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Yield in First Year

• Early harvest, 3 months, nets few fish
• After 5 months, harvest nearly 50
• 70 to 80 harvested by 7th month
• Average weight 1.25 pounds
• Survival after 7 months 85.7 in 9 ponds

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Pond Yield Verification -Arkansas catfish ponds,
93-96
Source University of Arkansas at Pine Bluff
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Why the difference in survival?

• Pond A used a different source of fingerlings
• Pond B fingerlings were stressed at stocking
• Ponds C and D had proliferative gill disease and
  columnaris infestations
• Pond D had catfish anemia

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Tips to Improve Survival

• Minimize the time between stocking and harvest
• Stock large and healthy fish
• Avoid winter carry-over
• Feed during the winter
• Utilize a fish health management program
• Seine and grade fish efficiently