Lake Raven is a 203.5 acre impoundment located within Huntsville State Park which is primarily known for its Largemouth Bass fishing. The lake is located about an hour north of Houston off interstate 45. Lake surveys have shown abundant populations of Largemouth Bass, Bluegill, and Redear Sunfish. But Catfish, both Blue and Channel, while being found in the lake are a result of stockings and have not maintained themselves through natural reproduction and recruitment. The management team responsible for the lake started to question why a waterbody of this size would not support the natural recruitment of Channel Catfish. The assumption has always been that the bass population was so great, that any natural recruitment of catfish were consumed before they could reach a catchable size. While this is a possibility, it’s not the only feasible explanation. Insufficient habitat for catfish spawning could also be the reason for no catfish recruitment in the lake. Catfish naturally spawn in holes; hollow logs, cavities between rocks, root wads, undercut banks, etc. They are what is called cavity nesters. A sexually mature male will select and clean a nest site and lure a female in to spawn with. After the female deposits an egg mass and it is fertilized by the male, he drives the female out of the nest and begins his guard duty. The male protects the eggs form predators, and fans them with his fins to keep the eggs aerated and free from sediment. Depending on the water temperature, it will take from 6 to 10 days for the eggs to hatch.
Our hypothesis is that there is insufficient spawning structure in Lake Raven for natural spawning to occur. The lake has very little downed timber or rocks for nesting sites and the bottom is mostly a silt layer. To test this we have developed a plan which is as follows. The fall of this year, 2017, we have requested to have 20,000 nine inch channel catfish stocked in Lake Raven with the expectation that a good portion of these fish will survive to become sexually mature. As of this article, 14,495 of the 20,000 have been stocked with more coming. In the late winter/early spring, we will place around 70 spawning structures in the lake at a 3 to 8 foot range and record the coordinates of each placement for relocation in the future. When water temperatures become conducive for spawning activity, around 80 degrees, the spawning structures will be monitored for activity using a water-proof camera. Jars with activity will be noted and rechecked for egg masses and fry. In the summer of 2018, fish sampling will be conducted to determine catfish abundance as well as the year class of the fish.
If there is no spawning activity found and the following fish sampling survey shows sexually mature catfish in the lake, the structures will be moved to new locations. If the sampling does not produce any sexually mature fish, the jars will be left and rechecked the following spring. In the event that there is spawning activity noted, then the following sampling survey give us the answers. If no year one fish are found, then predation is the problem, and we will continue to stock catfish as a “put and take” management strategy for Raven. If we do find the year one fish, then the lack of sufficient spawning structure was the problem and we can start using a more habitat improvement strategy of management. The hope of this experiment is to make a Lake Raven fishing experience more enjoyable for a variety of fishermen and to answer the question “can a Raven handle cats?”.
— Carl Vignali, Texas Parks and Wildlife Department