By Mike Pehanich
- Shawn Keulen’s 36-pound laker reported as 2nd largest fish taken from Lake Michigan so far this season
- Lake trout reproduction on Illinois reefs best on all Lake Michigan
- Goby addition to diet touted as key to natural laker reproduction
Capt. Shawn Keulen’s 36-pound lake trout was a big fish that shed light on an even bigger story — that lake trout are spawning successfully off Illinois shore and creating another world-class fishery.
On Sunday, July 29, Lake Michigan guide Capt. Shawn Keulen brought a giant lake trout to boat. The head looked menacing and atavistic, a throwback to some species of prehistory. Its weight registered over 36 pounds on at least one scale, according to local reports.
But to long-time followers of the Lake Michigan fishery saga, the catch was big beyond its physical dimensions.
Keulen’s laker is believed to be the second largest salmonid caught by hook and line this season, and it came within short reach of the Illinois state record lake trout of 38 pounds, 4 ounces, caught by Theodore Rullman in August of 1999.
More significantly, the catch highlights the revival of successful lake trout reproduction in Lake Michigan following decades of failure and disappointment.
“Illinois waters are loaded with lake trout,” said Rob Wendel, manager of the Lake Michigan Angler bait and tackle shop in Winthrop Harbor (www.lakemichiganangler.com ; phone 224-789-7627). “You can catch as many as you wish. It’s that good.”
The monster laker, the largest reported from Lake Michigan this season, stirred recollections of the bold efforts of Great Lakes biologists, anglers and volunteers to establish or reestablish viable populations of salmon and trout to Lake Michigan 60 years ago. The lake trout was the species impacted most heavily by a devastating sea lamprey invasion and locust-like alewife propagation in the middle of the 20th century.
The resultant program brought exciting Coho and Chinook salmon populations to the lake and buttressed fading steelhead numbers. But extensive efforts by Great Lakes states to bring back a self-sustaining population of the lake trout, a native predator, showed little success for almost half a century despite substantial annual stockings by the four Lake Michigan border states and the U.S. Fish and Wildlife Service.
That story line has changed dramatically in recent years, and, to the amazement of most, Illinois waters have staged the greatest lake trout comeback on the entire lake.
“We’re seeing high rates of non-stocked fish, wild lake trout, in our samples,” explained Vic Santucci, a Lake Michigan biologist for the Illinois Department of Natural Resources. “Anglers are also seeing more wild fish showing up in their catch due to our mass marking project in which we mark stocked fish with adipose clips and coated wire tags. We are seeing probably on average over 40 percent wild fish in our population since 2012.”
Lake trout are spawning successfully on reefs located off Illinois shores, most notably Julian’s Reef and Waukegan Reef. In fact, reefs from Chicago to the Wisconsin state line may host the most active and successful lake trout spawning grounds on the entire lake.
“As far as we know from annual samples, our percentage of wild fish is highest here in the southern basin,” continued Santucci. “We are seeing the highest percentage of wild trout in our samples. There are a lot of trout on the Midlake Reef in Wisconsin…but the last numbers I saw were in the high teens and 20- to 25-percent range (for wild fish). They go lower than that as you survey waters farther north.”
For bedding lakers, the cobble composition of the reefs is part of their charm. The chunk rock and small boulders comprise a lake bottom “where eggs can get into interstitial spaces and be protected from predators yet still get oxygen,” according to Santucci. Ironically, shells of dead quagga mussels, an invasive mollusc, may also factor to lake trout favor in the evolving structure of the reefs.
Forage mix also seems to be working to lake trout favor. And the lowly round goby, long viewed as an ecological nemesis, may be the unheralded hero of the wild lake trout revival.
“The prevailing theory is that our lake trout suffered from a dietary deficiency when they were eating alewives almost exclusively,” noted Wendel. “Now their diet has switched over to goby and other forage species as well. The diverse diet is healthier for the lakers, and the results are evident in lake trout catches today.”
Santucci acknowledges the theory and finds it credible. He noted that gobies are rich in thiamine, believed to be the long-missing yet critical nutrient for successful lake trout reproduction.
“Lake trout feed on just about anything they can catch,” he said. “In past decades, their diet consisted primarily of smelt and alewives, especially alewives. The gobies they consume today are quite possibly adding more vitamin B, thiamine, to their diet.”
Wendel reports fabulous and consistent lake trout fishing off Illinois shores, though anglers often need to plumb triple-digit depths to catch them in late summer. But ballooning lake trout numbers in Illinois waters have reinvigorated angler interest in the species. Spring shore fishing along the Chicago lakefront is now popular sport, and light tackle techniques have brought out the fighting best in a species often berated for its performance at the end of a lead core line in 100-foot depths. Many are finding the fish can fight!
So, welcome to Illinois, lake trout mecca!
Follow the Illinois pages of Share the Outdoors for more Lake Michigan news and how-to fishing information throughout the year.