Post by Deleted on Feb 8, 2015 6:09:29 GMT -5
Below is a summary of the proposed rule changes:
•Increases the minimum size limit on channel catfish, flathead catfish, and blue catfish from 10 inches to 13 inches on rivers and streams statewide, including the Ohio River. This would include both sport fishing and commercial fishing.
•Allows not more than one channel catfish to be taken per day that is 28 inches in total length or longer in lakes and streams statewide (both inland water and Ohio River) for both sport fishing and commercial fishing.
•Allows not more than one flathead and one blue catfish to be taken per day that is 35 inches in total length or longer in lakes and streams statewide (both inland water and Ohio River) for both sport fishing and commercial fishing.
The DNR commenced studying the decline in the catfish harvest in 2009 following the Natural Resources Commission Comprehensive Rule Review Project. At that time, a number of citizens and sportsmen organizations proposed increased protection for the catfish, citing concerns about potential commercial overharvest of big catfish for sale to pay lake operators.
Additional research by Dr. Robert Columbo of Southern Illinois University concluded that with the current regulations, only a modest increase in harvest could cause overfishing of catfish on the Wabash River. In particular, with the current 10-inch minimum size limit in Indiana’s portion of the Wabash River, the spawning potential ratio dropped below the 0.20 threshold at a fishing mortality of 33 percent, which means recruitment overfishing will occur if harvest exceeds 33 percent. This ongoing research suggests that flathead catfish are currently experiencing about 30 percent fishing mortality. Dr. Colombo noted that increasing the minimum size limits to 13 inches would lead to increased population abundance and higher angler catch rates and yield because it increases the reproductive potential of smaller/younger fish.
Recreational harvest estimates were not available when Colombo authored his report, but the 2005-2006 Wabash River creel survey indicated that around 70 percent of all catfish caught recreationally are harvested. Catch-and-release fishing was minimal, but did increase farther upstream. The 2009 report by Steve Donabauer reported that the current 10-inch minimum size limit allows harvest of immature fish and thus provides very limited protection for first time spawning catfish. Flathead catfish become sexually mature between 3-5 years and channel catfish at 4-5 years, yet flathead catfish are already nearly 12 inches long by age three and channel catfish are nearly 12 inches by age four. Donabauer also showed larger, older fish and lower annual morality and exploitation rates in the non-commercially fished section of the Wabash River.
At the completion of its five year study, the Division has concluded that the decline in catfish harvested can be attributed to a number of factors, including:
•Increased sport fishing interest in catfish, both for consumptive harvest and for a growing number of catfish catch-and-release tournaments;
•Increased commercial harvest above the long-term annual average, including the targeting of the largest catfish available for live sale to pay lakes;
•First-hand observations and anecdotal information from fishermen over a period of years that suggest the number and size of catfish appears to be declining, at least in some heavily fished locations;
•Unquantified but likely negative impacts on catfish from growing abundance of Asian carp as well as impacts of other exotic invasive species such as zebra mussels;
•Periodic water quality issues, most notably from non-point source pollution affecting Indiana’s rivers;
•Knowledge that current 10-inch minimum size limit does not protect catfish to reproductive size, which is closer to 15 inches;
•Research findings that document catfish are more heavily exploited in the commercially fished zones of the Wabash River.
Indiana is not the only state in the Midwest that has studied the decline in catfish harvest and concluded that changes were implemented or proposed in order to protect the species with the best reproductive potential:
•The Kentucky DNR now has similar catfish changes on the Ohio River for large, “trophy” catfish, with the exception of commercial fishing below the Cannelton Lock and Dam near Tell City in Perry County; Kentucky’s regulations allow commercial fishermen who have harvested more than 10,000 pounds of catfish in at least two of the last three years and others selected by a drawing (for a total of 50) to take up to four of these large catfish per day.
•Illinois DNR is proposing a change in catfish minimum length limits for the Wabash River. They are proposing a 13-inch size limit for both commercial and recreational fishers, and adding a 20 catfish per day bag limit for recreational anglers; previously they had a 15-inch minimum size limit for commercial fisherman, but no minimum size limit or bag limit for recreational anglers. Illinois DNR is also proposing the same ‘trophy’ catfish regulations as those proposed in this rule package (limit of one channel catfish over 28 inches and one blue and flathead catfish over 35 inches).
•Ohio allows only one big catfish (over 35 inches for blues and flatheads, 28 inches for channels) per day. Only five catfish can be taken per day, all catfish species combined.
•West Virginia allows only two blue catfish to be taken per day, and they do not allow commercial fishing.
•Virginia allows one blue catfish over 34 inches per day.
•Tennessee allows one catfish over 34 inches per day with a daily bag limit of five for all catfish harvested.
•Minnesota allows two flatheads to be taken per day and only one over 24 inches. They don’t allow commercial fishing in the Minnesota River.
•Mississippi allows one blue or flathead catfish over 34 inches per day.
•Oklahoma allows one blue catfish over 30 inches per day, and flatheads must be at least 20 inches.
The DNR has been coordinating with the Illinois DNR along with researchers at Purdue and Eastern Illinois University to develop similar regulations for the effective management of the Wabash River catfish populations. Collaboration with neighboring states is necessary for achieving common goals and protecting resources at a landscape scale.
By limiting the number of large (trophy) catfish that can be taken by anglers, catfish will be able to increase recruitment (survival of younger catfish), and ensure continued trophy angling opportunities. Furthermore, because large catfish eat smaller fish, large “trophy” catfish help control the populations of forage species such as gizzard shad. For example, invasive Asian carp are expanding in the Wabash River. Maintaining strong predator fish populations, such as large catfish, can help counter such invasions.