Purdue News

July 2, 1998 Biologist asks anglers to observe perch limits WEST LAFAYETTE, Ind. -- Yellow perch are disappearing from Lake Michigan, and Illinois-Indiana Sea Grant is working to help assure that this species remains a viable Lake Michigan fish. Illinois-Indiana Sea Grant's biological resources specialist Pat Charlebois encourages anglers to pay special attention to limits set by the Illinois Department of Natural Resources. "Anglers in Illinois waters are permitted to take only those yellow perch that are between 8 and 10 inches in length," Charlebois said. "Additionally, there's a daily bag limit of 15 per person. These regulations apply to all Illinois waters of Lake Michigan including the Chicago and Calumet rivers." Indiana has a daily limit of 15 per person with no size limit. The Lake Michigan yellow perch fishery reopened July 1 following closure during June when yellow perch reproduce. The yellow perch has long been a popular fish in the southern Lake Michigan region both for commercial and sport fishing. When studies indicated a significant decline in perch populations in Lake Michigan, Illinois, Indiana and other Lake Michigan states responded to recommendations of the yellow perch task group of the Great Lakes Fishery Commission by regulating commercial and sport fishing. "By complying with these regulations, anglers will contribute to the availability of yellow perch in the future," Charlebois said. "It is especially important that we preserve our yellow perch populations for cultural as well as ecological reasons. Yellow perch are native to Lake Michigan and are an important component of the ecosystem." Illinois-Indiana Sea Grant is funding research to help determine factors that affect Lake Michigan yellow perch survival and growth. John Janssen of Loyola University in Chicago is conducing a two-year study as part of a collaborative project with Michigan Sea Grant and Wisconsin Sea Grant. "We don't know if yellow perch are being eaten or if they're just starving to death," Janssen said. "To determine whether larval perch are getting enough food, we are using the ratio between RNA and DNA. DNA stays constant in an organism's cells, but RNA, which is used in the production of proteins such as muscle and enzymes, varies greatly in concentration inside cells and is a sensitive index of how much protein the cells are producing." Charlebois noted that the Fisheries Divisions of both Illinois and Indiana and the Illinois Natural History Survey also are conducting research on yellow perch populations. The Illinois-Indiana Sea Grant College Program is one of 29 National Sea Grant College Programs. Created by Congress in 1966, Sea Grant combines university, government, business and industry expertise to address coastal and Great Lakes needs. Funding is provided by the National Oceanic Atmospheric Administration, U.S. Department of Commerce, Purdue University, and the University of Illinois at Urbana-Champaign. CONTACTS: Charlebois, (847) 872-0140; e-mail p_char@ix.netcom.com; Janssen, (773) 508-3281. Compiled by Chris Sigurdson, (765) 494-8415; E-mail, sig@ecn.purdue.edu Purdue News Service: (765) 494-2096; e-mail, purduenews@purdue.edu To the Purdue News and Photos Page