Summer Smallmouth

OK, so we all enjoy the post-spawn smash fest.  But when the dog days of summer come, sometimes it gets harder to catch 'em.  And the first step to catching smallmouth in the summer is finding them.

Luckily, biologists can offer some clues as to where smallmouth go in the summer.  A study was done on Lake Opeongo in Algonquin Park to figure out exactly what these fish do when the weather gets hot.  Of course, you should take these results with a grain of salt- the fish in Opeongo may not act quite the same as those in big lakes like Erie and Simcoe.  But I think that some of the observations made by these researchers can at least give us some clues that can help us find these beasts.

The study found that during warm summer months, smallmouth inhabit deeper water during the daylight hours than at night- which comes as no surprise.  The fish generally stay in depths of around 5m during the day (~16 feet).  Interestingly, the range of inhabited depths across 1 hour intervals was relatively large (1).  This means that even during the day, some smallmouth are going to be in relatively shallow water at some point- presumably to feed.  The benefit of fishing shallow during the day is that you know the fish that are there are looking to eat, and so they tend to be easier to catch.

At night, smallmouth bass in Opeongo ascend to shallow water and remain there until sunrise.  The fish generally stay in depths less than 2m (~6 feet).  The study also found that larger smallmouth remain deeper in the water column relative to smaller ones at this time.  Try throwing some top-waters at night when the fish are shallower, especially if there's a moon out.  This makes it easier for the fish to see (keep in mind, bass are predators that rely mainly on sight).

Finally, the study found that smallmouth remain above the thermocline in the summer in Opeongo (1). Anglers often debate whether bass will ever go below this line.  Some say they won't, but many guys swear that they'll go below the thermocline, at least in some lakes.

I'll have a chance to test out some of these theories on Simcoe this weekend, and I'll post the results next week.  Just remember, knowledge is important, but it's no substitute for experience.

(1) C.D. Suski & M.S. Ridgway, "Seasonal pattern of depth selection in smallmouth bass" (2009) 279:2 Journal of Zoology 119.

Share this post