Smallmouth, big impact

Placid Lake angler caught a smallmouth bass last fall, prompting a fishing regulation change and a closer look
 

Last fall, Montana Fish, Wildlife & Parks fisheries biologists received a report that a smallmouth bass was caught by an angler in Placid Lake, marking the first confirmation of this non-native fish in the lake. The angler had a photo to verify the catch.

FWP fisheries biologists believe that an established population of smallmouth in Placid could have a significant negative impact on existing fish populations, particularly on native fish. Placid Lake has a lot of good habitat for smallmouth bass, so there is a risk of population expansion in the lake, depending on how many smallmouth are already living there.

Anglers play an important role in answering the question of smallmouth numbers and in population control. The Fish and Wildlife Commission approved an emergency fishing regulation for smallmouth bass in Placid Lake last December. The new regulation requires Placid Lake anglers to report any smallmouth bass they catch, and to kill and turn the fish into FWP for analysis.

Data collected from anglers will help biologists to detect additional smallmouth bass in the lake and answer questions about their age, numbers, viability and origin. Aside from angler reports, FWP is assessing what other population monitoring methods and responses might be warranted.

FWP believes that smallmouth bass were likely an illegal introduction into Placid Lake. To read more about illegal fish introduction, click here.

The lake is a popular kokanee, largemouth bass and westslope cutthroat trout fishery that would be impacted by an established smallmouth population. Migratory native bull trout would also be negatively impacted by a self-sustaining smallmouth bass population. 

This is not the first time new, non-native fish were detected in the lake in recent years. Northern pike were found in the lake in 2020, but no more pike have been sampled in follow-up surveys. The regulation for northern pike is the same as the new smallmouth bass regulation.