Connect with us

Report an Invasive Species

Smallmouth Bass

Smallmouth Bass

Smallmouth Bass

(Micropterus dolomieu)

Identification and Reproduction


  • Medium-sized, deep-bodied fish with green to olive back and sides and yellow to white belly.
  • Body often has dark vertical broken bars with 9 to 11 dorsal fin spines.
  • Shallow notch between dorsal fins.
  • Upper jaw does not extend beyond eye.


  • Smallmouth bass reproduce to bear a substantial number of offspring by spawning.
  • The smallmouth is a dioecious animal, with separate male and female individuals.  
  • The fusion of meiotically-produced haploid gametes, those being sperm from a male and eggs from a female, leads to the formation of diploid zygotes.

Habitat & Ecology

  • Clear, rocky lakes and rivers.
  • Shoreline rocks and points, offshore shoals, deep water.
  • Similar to trout habitat but with a wider range of temperatures.
  • Smallmouth Bass are considered top predators and can reduce native fish populations or alter their behaviour. 


  • Smallmouth Bass are considered top predators and can affect the native food web by reducing small invertebrates and fish.
  • It has been found to feed upon migrating salmon smolts and may pose a threat to salmon populations if the timing of the salmon run coincides with active bass populations.