Species · Micropterus dolomieu
Smallmouth Bass
A hard-fighting bass that anglers moved into British Columbia, which the Kootenay rules now treat as a fish to remove rather than protect.
Family
Centrarchidae
Origin
Introduced
How to tell it
The smallmouth bass is a sunfish from central and eastern North America, and it is not supposed to be in British Columbia. The province’s invasive species alert says it got here mainly through deliberate introductions for sport fishing, and also by swimming: natural dispersal from the United States up the Columbia River and other rivers that cross the border. The Royal BC Museum dates the first arrivals to 1901, when fry and fingerlings went into lakes on Vancouver Island and the mainland. It is now established on Vancouver Island and the Gulf Islands and in the Kootenay, Okanagan, Thompson-Nicola and Cariboo regions.
It is a good fish on a rod, which is the whole problem. The museum puts it bluntly: smallmouths are a favourite of anglers, who illegally stock them in lakes and rivers. Once in, they eat what fits. The provincial alert lists aquatic invertebrates, juvenile fish, amphibians and even small birds, and warns that they can feed on juvenile salmon and carry parasites harmful to native fish. In the Kootenays the rules reflect that. Bass are closed to fishing across Region 4 except on named waters, and on most of those named waters there is no limit on how many you keep.
So this page is about recognizing one, knowing where the rules let you fish for it, and not helping it go anywhere new.
The quick read
A grey-green to brown bass with dark vertical bars on its sides, a white belly and a mouth that reaches only to below the eye. It likes clear water over gravel and rock, holds under logs and docks, and goes deep and quiet in winter. In the Kootenays you may fish for bass only where the Region 4 tables name a water; everywhere else bass are closed. Where it is open, the province is happy for you to keep them.
Range in British Columbia
The provincial alert names southern Vancouver Island, the Okanagan, Thompson and Kootenay regions, and the Beaver Creek watershed in the Cariboo. The Invasive Species Council of BC lists it as a Management species on the province’s priority invasive species list.
In the Kootenays
The guide lists smallmouth bass on the Pend-d’Oreille River, on Erie Lake west of Salmo, on Beaver Creek in the Lower Arrow Lake watershed, and on Edith Lake near Wardner, among others. Several more creeks on the lower Columbia carry the species only as an inference from connected water, which is a guess about where a fish could swim, not a record of one.
The rules point the same way. The 2025–2027 Region 4 tables set an unlimited bass quota on the Columbia River from Keenleyside Dam to the Washington border, on the Kootenay River from Brilliant Dam to the Columbia, on the Pend d’Oreille River including the reservoirs behind Waneta and Seven Mile dams, and on Erie Lake. That is the lower Columbia system, the route the alert describes bass using to come north.
Edith Lake is a caution. The guide lists smallmouth there, but the 2025–2027 tables give it no bass exception, so under the regional rule bass there are closed. A listing tells you a fish has been recorded; it does not tell you that you may fish for it.
Habitat and behaviour
The provincial alert describes smallmouth bass living in reservoirs, ponds, rivers and streams, in the clear water of the shallows over gravel with little vegetation, often under submerged logs and docks. FishBase describes adults on shallow rocky lake shores and in clear, gravel-bottomed runs and pools of rivers. In winter they lie dormant in colder, deeper water and move back to the shallows to feed and spawn as the water warms.
That habitat is the main way to tell a smallmouth water from a largemouth bass water. Largemouth in the Kootenays are the fish of warmwater lakes such as Duck Lake. Smallmouth want rock, gravel and clear water, in rivers as well as lakes.
FishBase gives the adult diet as crayfish, fish and aquatic and terrestrial insects. On the lower Columbia that means the sculpin, baitfish and fry and crayfish along rocky margins.
Confusing species
The alert says the two bass are separated by side pattern and mouth size. A largemouth has a dark horizontal stripe running from the gills to the tail and a mouth that extends past the centre of the eye. A smallmouth has vertical bars and a mouth that ends below the eye. The regulations treat both under one word, bass, so the same quota and closures apply whichever you catch.
The alert also notes that a smallmouth’s two dorsal fins are joined, spiny at the front and soft-rayed behind. On the lower Columbia the other introduced predators you may meet are walleye and northern pike, each with its own rules in the same tables.
A reliable first outfit
Nothing here is specific to British Columbia, and this section is general fly-fishing practice rather than agency advice. A six or seven weight rod with a floating line and a sinking-tip line covers it. Fish where the alert says the fish live: rocky points, gravel shoals, logs and docks. A weighted crayfish or sculpin pattern, or a dark Woolly Bugger, stripped along the bottom near rock is the starting point, and a Muddler Minnow fished higher covers the baitfish. The streamer fishing page has the method.
Spawning season
Male smallmouth build a nest along the water’s edge, and after the female lays her eggs she leaves; the male guards the nest and the young. The Invasive Species Council of BC says they spawn when the water passes 15°C, and that a female may spawn several times a year with up to 10,000 eggs each time. That is how a few illegally moved fish become a population.
Rules that apply
The 2025–2027 Region 4 Kootenay regulations set the regional bass quota at zero and close bass to fishing, with exceptions listed water by water. The notice to anglers says it is illegal to fish for bass, perch, pike or walleye in the region except on waters listed in the tables, as part of the province’s response to illegal fish introductions. On most listed waters the bass quota is unlimited; Duck Lake in the Creston Valley Wildlife Management Area has its own limit and a spring catch-and-release period. The province’s summary of changes for this edition lists an unlimited bass quota for Columbia Lake and the Columbia River.
The Freshwater Fisheries Society of BC explains the logic. Bass are game fish under the regulations, so where the rules allow, you may keep the invasive fish you catch. Where a fishery is closed, you must not target the species and should release any you catch by accident.
The general regulations apply everywhere: do not keep any live fish in your possession in the wild, do not move live fish or transplant them into any water, do not keep angled fish alive in a livewell or on a stringer, and never use live fish as bait. The provincial alert asks anglers to report smallmouth found in new places through the Report Invasives app or the province’s online form. Check the current regulations and in-season changes before you fish; this page is not the synopsis.
Frequently asked questions
Is this a smallmouth or a largemouth?
Look at the mouth and the sides. If the jaw ends below the eye and the sides carry dark vertical bars, it is a smallmouth. If the jaw runs past the middle of the eye and a dark stripe runs along the side from gill to tail, it is a largemouth.
Can I keep the smallmouth I catch?
On a water the Region 4 tables open to bass, yes, and on most of them there is no limit. On any water not listed, bass are closed: do not fish for them, and release one caught by accident. Never take one anywhere alive.
Why would the province want anglers to kill a sport fish?
Because it was put here. The alert links smallmouth bass to the decline and local loss of native fish and amphibians where they have been introduced, and to risks for juvenile salmon. An unlimited quota is a way to keep their numbers down where they are already established.