01-09-2013, 12:10 PM
Catfish angling has grown in popularity over the last decade and, in particular, so has the interest in trophy catfish. Blue catfish (hereafter, blues) are a species of catfish native to the Ohio River drainage. Blues can grow to a very large size in the right situation. The Ohio state record is a 96-pound blue caught in the Ohio River in 2009. The world-record blue was caught in Kerr Reservoir, Va., in 2011 and weighed a whopping 143 pounds! The Division of Wildlife initiated a study in 2009 to assess the success of stocked blue catfish in two reservoirs. This study was specifically intended to determine if blue catfish will remain in these reservoirs to provide additional catfish angling opportunities, and potentially trophy-sized fish.
Blue catfish fry were stocked at the Hebron State Fish Hatchery in Licking County in the springs of 2009 and 2010. They were raised there for approximately 16 months. The yearling (9 to 12 inches) blues from the hatchery ponds were stocked into Dillon Reservoir in October 2010 and Hoover Reservoir in October 2011.
Dillon Reservoir is an impoundment of the Licking River in Muskingum County that is regulated by the Army Corps of Engineers for flood control. Hoover is an impoundment of Big Walnut Creek in Franklin County which is owned and operated by the City of Columbus as a source of municipal drinking water. Dillon is approximately half the size of Hoover (1,370 acres versus 2,880 acres, respectively) and about half as deep (average depth is 9.2 feet versus 22.3 feet, respectively), but Dillon drains about four times as much land area (1,693 sq. km versus 495 sq. km, respectively). Water flows through Dillon much more quickly than at Hoover because of these differences; on average it takes about nine days to turn over the entire volume of Dillon, compared to approximately 190 days for Hoover. These reservoirs were chosen by the division because of these hydrological differences, and also because they have surpluses of prey fish (primarily gizzard shad) that are capable of supporting additional predators.
Each year, approximately 3,000 of the 13,000 stocked blues were marked with bright orange tags. Tags were imprinted with a phone number anglers could call to report catching a tagged blue. Anglers that reported catching a tagged fish received an award for their catch. Each year, 50 fish were also implanted with acoustic "pingers" which were used to track the movements of individual blues in these reservoir/river systems. These pingers transmit a coded signal approximately every 90 seconds that can only be decoded using a specialized hydrophone that logs the date and time a ping is heard. Hydrophones were placed at various locations within the reservoirs, in tailwaters below the dams, and in the river systems farther downstream.
Results from the two years of this study were very different. The angler reports and the hydrophone data indicated that a majority of the Dillon blues went through the dam shortly after being stocked. The hydrophone in the Dillon tailwater revealed that most of these fish exited the reservoir during a two-week period in late November when the reservoir was being drawn-down to winter pool. More than 90 percent of the anglers that caught a Dillon-stocked blue reported catching their fish in the Licking or Muskingum rivers, downstream of the reservoir. In fact, some of the Dillon-stocked fish have been captured in the Ohio River as far away as Parkersburg, W.Va.! In contrast, none of the blues stocked into Hoover were detected below the dam, and 100 percent of the angler reports were regarding fish caught in the reservoir. The blues stocked into Hoover have remained in the reservoir and are expected to continue to provide angling opportunities over the next several years. As these fish continue to grow they will potentially attain trophy sizes.
The results of this study have shown that stocking blues can produce additional catfish angling opportunities in certain Ohio reservoirs under the right conditions.
Blue catfish fry were stocked at the Hebron State Fish Hatchery in Licking County in the springs of 2009 and 2010. They were raised there for approximately 16 months. The yearling (9 to 12 inches) blues from the hatchery ponds were stocked into Dillon Reservoir in October 2010 and Hoover Reservoir in October 2011.
Dillon Reservoir is an impoundment of the Licking River in Muskingum County that is regulated by the Army Corps of Engineers for flood control. Hoover is an impoundment of Big Walnut Creek in Franklin County which is owned and operated by the City of Columbus as a source of municipal drinking water. Dillon is approximately half the size of Hoover (1,370 acres versus 2,880 acres, respectively) and about half as deep (average depth is 9.2 feet versus 22.3 feet, respectively), but Dillon drains about four times as much land area (1,693 sq. km versus 495 sq. km, respectively). Water flows through Dillon much more quickly than at Hoover because of these differences; on average it takes about nine days to turn over the entire volume of Dillon, compared to approximately 190 days for Hoover. These reservoirs were chosen by the division because of these hydrological differences, and also because they have surpluses of prey fish (primarily gizzard shad) that are capable of supporting additional predators.
Each year, approximately 3,000 of the 13,000 stocked blues were marked with bright orange tags. Tags were imprinted with a phone number anglers could call to report catching a tagged blue. Anglers that reported catching a tagged fish received an award for their catch. Each year, 50 fish were also implanted with acoustic "pingers" which were used to track the movements of individual blues in these reservoir/river systems. These pingers transmit a coded signal approximately every 90 seconds that can only be decoded using a specialized hydrophone that logs the date and time a ping is heard. Hydrophones were placed at various locations within the reservoirs, in tailwaters below the dams, and in the river systems farther downstream.
Results from the two years of this study were very different. The angler reports and the hydrophone data indicated that a majority of the Dillon blues went through the dam shortly after being stocked. The hydrophone in the Dillon tailwater revealed that most of these fish exited the reservoir during a two-week period in late November when the reservoir was being drawn-down to winter pool. More than 90 percent of the anglers that caught a Dillon-stocked blue reported catching their fish in the Licking or Muskingum rivers, downstream of the reservoir. In fact, some of the Dillon-stocked fish have been captured in the Ohio River as far away as Parkersburg, W.Va.! In contrast, none of the blues stocked into Hoover were detected below the dam, and 100 percent of the angler reports were regarding fish caught in the reservoir. The blues stocked into Hoover have remained in the reservoir and are expected to continue to provide angling opportunities over the next several years. As these fish continue to grow they will potentially attain trophy sizes.
The results of this study have shown that stocking blues can produce additional catfish angling opportunities in certain Ohio reservoirs under the right conditions.