Smallmouth bass

Smallmouth bass

Micropterus dolomieu

Common name:

Smallmouth bass

Scientific name:

Micropterus dolomieu

Alternative common names:


The smallmouth bass is a small predatory fish, reaching up to 60mm in length and 2kg in mass. It is an olive to coppery-yellow colour above, with darker olive vertical stripes and a dusky white underneath. Breeding usually occurs in early summer in shallow waters. Smallmouth bass has caused a decline in indigenous species through environmental degradation and predation.

Additional Information

Where does this species come from?

North America

What is its invasive status in South Africa?

NEMBA Category 1b in National Parks, Provincial Reserves, Mountain Catchment Areas and Forestry Reserves declared in terms of the Protected Areas Act. NEMBA – Category 2 for release into damns within descrete catchment systems in which it occurs. NEMBA – Category 3 in all rivers, wetlands, natural lakes and estuaries in which it occurs.

Where in South Africa is it a problem?

Throughout South Africa, widespread in temperate regions (Eastern and Western Cape)

How does it spread?

Why is it a problem?

The smallmouth bass has had a devastating effect on indigenous species, the main factor of the decline in indigenous species, being environmental degradation. Predation on indigenous organisms has also had a significant effect on ecosystems.

What does it look like?

Predatory fish, with a large head and mouth, reaching up to 5kg in weight and 60cm in length. Olive to coppery-yellow colour above, with darker olive vertical bars, dusky white underneath and red eyes.

Habitat: Freshwater, preferring rocky pools and dams.

Breeding: Occurs in early summer. Nest built in shallow waters.

Leave a Reply