Lake Mary Ronan pike population threatens salmon fishery
LAKE MARY RONAN – Cast your line out in Lake Mary Ronan and you’ll likely find a northern pike on the other end.
On Dec. 4, Montana Fish, Wildlife and Parks fish biologists Kenneth Breidinger and Sam Bourret held a forum at the Mountain Meadow Resort located along the shoreline of Lake Mary Ronan to discuss the lake’s invasive non-native northern pike population.
Northern pike are a long muscular fish with a beak-like mouth full of extremely sharp teeth. They tend to be dark green to olive-brown with light-colored spots and dark banding on the tail and fins.
Being an aggressive apex predator, northern pike primarily dine on other fish, although they have been spotted chomping on anything that gets close enough, including frogs, birds and small mammals. These powerful fish grow between 10 and 25 pounds.
In June of 2019, the population of northern pike in Lake Mary Ronan increased to the point where FWP enacted an emergency regulation change. All anglers are now required to turn in any northern pike caught in the lake within 10 days of capture.
Addressing the group of more than 40 Lake Mary Ronan residents who gathered for the forum, Bourret said that data collected from the pike caught and turned in by anglers will assist FWP researchers establish population size, the fish’s viability within the lake and help the department determine the best possible management opportunities. Northern pike were first officially documented in Lake Mary Ronan back in 2014 after an angler caught one and turned it over to FWP officials.
Non-native game fish don’t just show up in a lake’s ecosystem Breidinger said. Based on the sudden appearance of adult northern pike in the lake he added that he is quite certain “bucket biologists” illegally transplanted the invasive species by the buckets full into Lake Mary Ronan.
Residents are concerned with the development. “I don’t see why these guys seem to think every lake has to have pike in it,” said Lake Mary Ronan resident Curtis Reber. “It’s nice to have a little diversity in a lake that’s not dominated by pike.”
In 2018, using forensic geochemistry and the otoliths (a calcium carbonate structure in the inner ear bones of fish that contain unique geochemical identifying tracers much like a tree’s concentric growth rings) from a northern pike turned in by an angler, Bourret was able to confirm and document the first reproductive northern pike population in Lake Mary Ronan. While the population density of northern pike is currently unknown, Bourret believes there is a high risk of population expansion in the lake.
An expanding northern pike population would have a significant negative impact on the rainbow trout, largemouth bass and yellow perch fisheries, but the danger posed by the pike to the prized kokanee salmon fishery is particularly troublesome to both FWP officials and Lake Mary Ronan residents.
With 400,000 kokanee salmon planted annually into the lake by the FWP, Lake Mary Ronan is one of the most popular and productive salmon fisheries within the state. Kokanee in Lake Mary Ronan also serves as the sole source for eggs used for kokanee restocking programs throughout Montana.
According to Bourret, FWP will continue its data gathering by radio tagging pike in the spring to find out where and when they spawn. Anglers who catch northern pike in Lake Mary Ronan are required to report the catch to FWP within 24 hours by calling 406-752-5501 and submitting the entire fish to a Montana Fish, Wildlife and Parks office within 10 days. Edible portions of the fish may be returned to the angler upon request.
Anyone who witnesses a fish and game violation or property vandalism anywhere in Montana can report the crime by calling 1-800-TIP-MONT (1-800-847-6668). Callers will remain anonymous and may be eligible for a cash reward.