A national panel of fisheries scientists has recognized the Pennsylvania Fish and Boat Commission (PFBC) for its work on a decades-long research project which demonstrated that restrictive harvest regulations can increase panfish populations while creating a positive fishing experience for anglers targeting these popular fish.
The American Fisheries Society (AFS) selected the PFBC Division of Fisheries Management for an outstanding project award in the Research and Surveys category of its 2010 Sport Fish Restoration Project Award Program, which recognizes excellence in fisheries management, research and education.
The study used both contemporary and historical fisheries data dating back to 1982 with more intensive and formal sampling conducted from 1999-2007. The panfish program was initially proposed by fisheries management staff in 1994 after agency biologists and anglers alike became concerned about apparent declines in numbers of large or “keeper” size sunfish, crappie and yellow perch at some lakes.
Conducted in cooperation with the U.S. Geological Survey’s Cooperative Fish and Wildlife Research Unit at Penn State University, the project sought to increase the number of “large” panfish through size and creel limits and to increase anglers’ satisfaction with their fishing experience.
“Because they are widely available and generally taste good, panfish are one of the most popular fish targeted by anglers,” said Dave Miko, chief of the PFBC Division of Fisheries Management and the project leader for the research study. “In fact, PFBC surveys have shown that nearly half of all fishing time is spent pursuing them. And because panfish are easy to catch, they play a key role in introducing new and young anglers to the sport.”
Historically, the PFBC had encouraged panfish fishing under the belief that the species was underutilized and were not likely to be overfished. Anglers were allowed to harvest 50 fish per day with no minimum size limit. But in 1999, after almost five years of planning and coordination and amid the concerns about the decline in larger panfish at some waters, the PFBC placed size and creel limits on select reservoirs and lakes meeting biological criteria and where it was felt that angler harvest reduced the size structure of panfish populations.
The regulations established minimum size limits of 9 inches for crappie and yellow perch and 7 inches for sunfish. Creel limits also were reduced to 20 fish per species group (i.e. crappie, yellow perch and sunfish) and a combined total of 50 fish per day.
After analyzing data from this long-term project during 2008-09, PFBC scientists believe that restrictive regulations can be an effective technique for increasing panfish populations in some waters where angler harvest is a major limiting factor. For example, catch rates of legal-size crappie in trapnets, used to sample panfish, tripled in the treatment lakes over the 10-year period following implementation of the regulations.
Catch rates remained unchanged in control lakes, which had remained under statewide regulations, providing strong evidence that the experimental regulations and not natural variation worked to increase the population. Results for sunfish and yellow perch were less definitive, but nonetheless positive, with trapnet catch rates nearly doubling in the treatment lakes and remaining unchanged in the control waters.
The final report of the research project is being reviewed by PFBC staff with an eye toward applying the project to other waters where the necessary criteria would be met and benefits would be anticipated. These reviews are expected to be completed by early summer, at which point the full results will be made available.
source: Pennsylvania Fish and Boat Commission
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