How Bass Eat

This week we're going to talk about the different ways smallmouth and largemouth attack their prey.  Although the two species share similarities, they actually eat using different physical mechanisms.  For fishermen, this might- and I stress the word might- mean that certain lures will be more effective at catching smallmouth, whereas other lures will be more effective at catching largemouth.  Let's take a look at these differences.




Feeding postures of Smallmouth (A) and Largemouth (B)
See footnote (1)



The first difference between the two species is feeding posture.  As you can see in the drawing on the left, smallmouth tend to remain relatively horizontal when capturing prey, whereas largemouth have a more vertical approach (the video below seems to confirm this).  So, for example, the profile of a shaky head will match up nicely with the feeding posture of a largemouth.  Largemouth, relatively speaking, are not bottom feeders, so it's a good idea to give them something easier to grab.  Smallmouth, on the other hand, spend more time in rocks and are used to feeding on bottom dwelling prey like crayfish.  It'll be easier for them to pick up a plastic on a Carolina rig or a crankbait that's being dragged along the bottom.  I'm not saying you won't catch largemouth using these techniques -- but why not make it easier for the fish to get your bait in its mouth?

The second difference has to do with the reliance on suction feeding versus biting.  Largemouth bass have a tendency to exhibit "suction and engulfing, more frequently than the biting mode of prey capture" (1).  On the other hand, smallmouth have a tendency to bite their prey.  When fishing for largemouth, then, you should feel confident setting the hook as soon as you feel a fish take your bait, since the fish has probably inhaled it.  If, however, you're fishing for smallmouth and you find that you're getting hits but not getting any fish on, you might have to wait an extra 1/2 second or so to set the hook.  The fish may be biting your bait but not immediately taking it entirely into its mouth.

As I've mentioned, understanding these differences may not have a huge impact on your fishing success.  It's not a factor like water temperature or water clarity that we know influences how and when fish feed.  But on a slow day when nothing seems to be working and the fish are inactive, try messing around with different rigs, keeping in mind that smallmouth and largemouth eat differently.  And remember, knowledge is important, but it's no substitute for experience.