Decades of raw muskie creel data in Illinois: Picking the brain of Ray Thompson

When Ray Thompson mapped Braidwood Lake before it opened to the public, he stuck one piece of bad information in it. Sure enough, an unnamed publication ripped off his map without credit, including the bad data point.

Data means something to Thompson, who worked in architecture and engineering before retiring. Thompson, the chairman of the Illini Muskies Alliance, has kept an annual voluntary creel survey on anglers catching muskie in Illinois going for more than three decades. It is the most comprehensive database of its kind.

It fascinates me, in part because it is an important and utterly valuable source of information and also an imperfect source of data.

In April 1987, a green-card muskie reporting system began, co-sponsored by the Illinois Department of Natural Resources (Department of Conservation) and the Illini Muskies Alliance (muskie clubs and groups in Illinois). If you know anything about the Type A personalities or rugged individualists in muskie fishing, that the IMA has hung together is a notable feat.

‘‘Some lakes, nobody turns them in; other lakes, there’s lots of participation,’’ Thompson said. ‘‘It can lead to faulty reporting.’’

For instance, only 11 muskie were registered last year at Shabbona Lake. There might have been that many caught in a single day there. Mill Creek has muskie, but mum is the word. Then there’s the Fox Chain O’Lakes, where the numbers are skewed up because it is largely the home waters for three active Muskies Inc. chapters: Chicagoland Muskie Hunters, Fox River Valley and South of the Border.

The survey started with 27 lakes and is now around 70 waters, another remarkable feat. The survey started solely with green cards but about 15 years ago expanded to include Muskies Inc. data from Illinois and now online entry.

The online and green-card reporting average 110 a year and Muskies Inc. data averages 464 for a total of 574 total. That’s a fraction of the muskie caught annually in Illinois, but it can give a picture over the years.

‘‘In 2010, there were 1,261; it was a real good year for fish,’’ Thompson said. ‘‘People complained last year was a bad year, but it was an average year.’’

Thompson knows there are ‘‘fast-action lakes and trophy lakes — lakes where . . . if you catch one, it is a good one.’’

So I asked for his observations from over the decades. Lake Shelbyville was the muskie lake in Illinois until a mysterious die-off struck and stuck in recent years. Kinkaid Lake and the Chain are usually tops for numbers. The Chain and Shelbyville are the trophy lakes, with Lake McMaster (“not a lot of fish, but No. 3 on list all-time for 50-inch fish”) and Lake Storey (“consistent but small, produced seven of 50 inches”) in the mix and Evergreen Lake ‘‘coming on.’’

There are anomalies. Independence Grove has produced three muskie of 50 inches or longer, and Mallard, a lake in the Forest Preserve District of DuPage County, has produced a 48-inch muskie.

If you want to wade into data on muskie, go to the IMA’s site at illinimuskiesalliance.org.