Smallmouth Size Increasing?

This one was taken yesterday, and we're catching smallmouths so big, they won't fit in the frame. (Actually, a little better camera work would help immensely, but it's no biggie.) Jesting aside, they do keep getting bigger every year. Suddenly, multiple 6-pounders are being weighed in at tournaments that never had any over 6 weighed in during previous decades — the Sturgeon Bay Open on Lake Michigan serving as a prime example.

Last year was undoubtably my best ever for smallmouth size over 6 pounds, and we caught them in a number of venues, including Chequamegon Bay, where my friend, guide Chris Beeksma plies his trade. "If it's over 21 inches long, it typically weighs over 6 on the Bay," he says. "They're pretty stout, here. They grow rounder instead of longer." The Bay is on Lake Superior, of course. Most people think lake trout and steelhead when the subject turns to Superior, but the smallies grow huge in several places along the South Shore.

It takes 22 inches or more on most of the inland lakes I frequent to top 6 pounds, with the possible exception of late fall and early spring.  But why are we suddenly seeing so many more that size than at any point in the past?

Some people say it's the gobies, but we have no gobies on these inland lakes. In fact, there are no invasive species of minnows on any of the lakes I'm talking about.

My theory is, smallmouths have had longer growing seasons over this past decade than at any previous point during my lifetime. Spring has been arriving earlier and winter setting in later than ever before. According to NASA, the 10 hottest years on record have occurred in the past 14 years, on a global basis, with 2005 being the hottest ever recorded. It certainly seems like smallmouths are putting on more inches and pounds per year in a band stretching from the northern reaches of Iowa north into Canada, to the far northern extremes of the natural range of smallmouth bass. In that part of the world, the weather is making conditions closer to optimum for growth. Too much heat may have the opposite effect, but in places like Michigan, Minnesota, and Wisconsin, extremes on the cold end of the scale — along with shorter spring and fall periods — historically worked against optimum growth.

Just a theory. Whatever's causing it, I'm not complaining. The chances for catching a smallmouth over 8 pounds in this part of the world certainly seem better than ever.