Truman Reservoir and Lake of the Ozarks Blue Catfish Management Changes Considered
MDC is considering protective regulations for blue catfish on Truman Reservoir and its tributaries in and effort to reverse the trend of declining intermediate- and large-size blue catfish numbers in those waters. For Lake of the Ozarks, potential regulation changes would be preemptive to help protect existing blue catfish numbers and prevent a similar decline of intermediate- and large-size blue catfish.
The growing problem
For a number of years Department of Conservation staff have been concerned about potential overharvest of catfish in Truman Reservoir, especially blue catfish. Anglers have also expressed concern about the decline of this blue catfish population. Recently, we have seen the same trend starting on Lake of the Ozarks.
In our 2002 Statewide Catfish Angler Survey, 35.1 percent of respondents indicated the quality of catfishing at Truman Reservoir had declined over the last 10 years, while 11.7 percent of respondents indicated catfishing had improved. 27.7 percent reported that catfishing quality had stayed the same and 25.5 percent reported they didn’t know. MDC staff also documented high harvest and slow growth of blue catfish at Truman Reservoir during our Reservoir Catfish Evaluation Project from 2004 to 2008. Research showed a blue catfish harvest rate two to three times higher than reported in similar studies nationwide.
MDC convened a working group in 2009 to summarize past catfish management at Truman Reservoir and at Lake Ozark and to develop future management objectives and regulation proposals to address the growing problem.
Why it's a problem
In comparison to most other game fish species, catfish (especially blue and flathead) are extremely long-lived and slow growing. Blues and flatheads can easily live to 25 or 30 years with weights approaching or even exceeding 100 pounds.
Due to high fishing pressure and angler harvest, the numbers of quality-sized blue catfish in Truman have steadily declined since the mid 1990s. These conditions are preventing blue catfish from reaching their full potential.
It takes a blue catfish in Truman and Lake Ozark about 15 years to reach 31 inches in length and a weight of about 12 pounds.
A 15-year-old blue catfish that is 31 inches today can easily live another 10 to 15 years and reach 60 or 80 pounds. For that to happen, however, we have to make sure that anglers don’t harvest them all. Our data indicates that anglers are harvesting too many blue catfish before they reach their growth potential.
For slow-growing fish such as blue catfish, once a decline occurs, it takes a significant amount of time (six to seven years) to start reversing the trend and rebuilding the population.
A community-supported solution
In May 2010, we held a series of stakeholder meetings to discuss these potential regulations. Those in attendance included recreational and tournament anglers, catfishing guides, organized catfish angler groups, baitshop and marina owners, media representatives, judges and prosecuting attorneys, local chambers of commerce, state representatives and other government and non-government groups such as the Department of Natural Resources, U.S. Army Corps of Engineers and Ameren UE.
The majority of attendees at these meetings were in favor of potential regulations. Since these meetings, we continue to receive and document public input.
Public input, along with angler-survey and population-evaluation data, will all be considered prior to submitting potential regulations.
Goals of potential regulations
- Protect intermediate-size blue catfish and increase the number of quality-size blue catfish;
- Increase harvest of smaller blue catfish below the protected slot to improve growth;
- Retain catfish anglers on the affected waters;
- Maintain good relations with non-angling stakeholders; and
- Continue to promote local economic benefits of catfishing
Potential regulations
After examining nearly two dozen different possible regulations and how those regulations might affect blue catfish, two options stand out as being the most effective. Both options would protect intermediate-sized blue catfish while still allowing limited harvest of larger blue catfish and continuing to allow anglers to harvest adequate numbers of blue catfish for the table.
In general, potential regulations would set a daily limit of 10 blue catfish (twice the daily limit when compared to current regulations) and would include a protected slot length limit. Fish within a protected slot limit would have to be returned to the water unharmed, immediately. Anglers would be permitted to keep either one or two blue catfish larger than the upper end of the protected slot. The possession limit would be twice the statewide daily limit.
The potential regulations being considered would apply to Truman Reservoir, Lake Ozark and their tributaries including the no-boating zone below Truman Dam. For the no-boating zone, flathead and channel catfish regulations would revert to current statewide regulations.
In the no-boating zone below Truman Dam, the statewide daily limits of five flathead catfish and 10 channel catfish would apply. The possession limit would be twice the statewide daily limit.
The desired results
The potential regulation changes would provide harvest protection for intermediate and larger blue catfish, which are currently being harvested at an excessive rate. This protection will allow more blue catfish to reach larger sizes.
It will also encourage the harvesting of small blue catfish. The numbers of small blue catfish in both lakes is adequate, if not excessive. Encouraging more harvest of small blue catfish has the potential to reduce competition among blue catfish, which may actually improve growth. Encouraging the harvest of more small blue catfish will also allow anglers to take fish home for the table.
Based on biological projections, the number of fish harvested would remain similar or increase compared to existing conditions. With added protection for intermediate sized blue catfish, we project the numbers of larger sized fish in the population would increase.
Because the fishery on Lake of the Ozarks is currently in good condition compared to Truman, improvements in the fishery would still occur, but would likely be less significant than those predicted for Truman
Should a new regulation be adopted, a long-term evaluation of the regulation will be conducted. Because of the slow growth exhibited by blue catfish, it will take six to seven years before the population will start to show any significant response to the regulation.
How the process works
If a regulation is proposed, it would go to the MDC Regulations Committee for Wildlife Code review. With the Director’s approval, the proposed regulation changes would then be presented to the Conservation Commission for approval. If approved by the Commission, the regulation changes would then be filed with the Secretary of State’s Office and will be posted for public comment.
MDC welcomes comments to regulations we are considering. Questions or comments can be directed to Truman Reservoir Fisheries Biologist, Mike Bayless (660-885-6981, ext. 253 or Mike.Bayless@mdc.mo.gov) or Lake Ozark Fisheries Management Biologist, Greg Stoner (573-346-2210, ext. 235 or Greg Stoner@mdc.mo.gov).
