Courtesy of the Oklahoma Department of Wildlife Conservation BLUE CATFISH SAMPLING/MANAGEMENT Fishing for trophy-size blue catfish has increased in popularity in recent years. Fisheries biologists across the state have begun to look at ways to manage these fisheries to ensure that the quality of these blue catfish fisheries is maintained. The Oklahoma Department of Wildlife Conservation (ODWC) has been collecting abundance and growth information on blue catfish populations around the state over the past several years. Blue catfish grow slowly relative to many other sport fishes. There is also a wide range in growth rates among lakes. Growth rates on Kaw, Keystone, Texoma, and Waurika were fairly good but blue catfish at Ellsworth, Eufaula, and Hugo had poor growth rates. A 10 year old blue catfish from Keystone averaged 25 inches whereas an age-10 blue catfish from Ellsworth only averaged 15 inches. A 10 year old blue on Texoma averaged 23 inches. Blue catfish from most lakes weigh 10-12 pounds at 30 inches. Even on the fast growing lakes it takes 12-14 years for blue catfish to get to 10 pounds. The largest fish in our sample came from Texoma (48 pounds) and was age 16. The oldest fish in our sample (24 years) came from Ellsworth, but was only 19 inches long. Total mortality rates (the percent of the population that dies every year by both natural causes and angler harvest) generally ranged between 20 and 30%. This is a relatively low rate of mortality compared to other sport fishes (total mortality rates for largemouth bass are usually around 50% and crappie mortality rates can be as high as 80%). However, because blue catfish grow so slowly, very few individuals ever make it to trophy size even with the low mortality rates. Remember that it takes about 12-14 years for a blue catfish to reach 10 pounds. Given the average mortality rate (25%), for every 10,000 age-1 blue catfish in a lake, less than 300 of these make it to 10 pounds. You can imagine how few ever make it to 50 pounds. These large blue catfish are very rare which makes them very valuable. We encourage anglers to eat the 1-5 pound blue catfish and take pictures of the large blues and return them to the lake unharmed.