Muskie magic? North Branch has it
Harrisburg — Beginning in 2017, the Pennsylvania Fish & Boat Commission will no longer stock muskies in the North Branch of the Susquehanna River.
They don’t need to.
Sampling conducted by agency staff on the river throughout 2016 determined the muskie population is supported through natural reproduction and the stocked fingerlings simply aren’t surviving.
Rob Wnuk, area fisheries manager for the Pennsylvania Fish & Boat Commission’s Northeast Region, said there is a lot to like about the river when it comes to muskies.
“There is good nursery habitat in the river and a good forage base of suckers and young carp. Muskies grow really well in the river,” Wnuk said, adding both the catch rates during sampling and growth rates of muskies in the river were high.
“The North Branch of the Susquehanna River was right up there with some of the best muskie rivers known in the country,” Wnuk said. “It was very impressive.”
Wnuk’s numbers back up the claim.
During 13 days of sampling on the river Wnuk and his crew captured 24 muskies, plus three more while sampling for other species for a total of 27. The adult muskies ranged in size from 14 to 44 inches in length.
Things are just as good for yearling muskies as well.
During 13 days of sampling in 2015, 31 wild young-of-the-year muskies were captured and six others were missed, for a catch rate of 2.85. The North Branch also has .48 young-of-the-year muskies per mile, exceeding the .24 figure Wisconsin uses to define a self-sustaining muskie population in its lakes.
Not only are the muskies in the river numerous, they’re also growing rapidly.
Wnuk’s data shows that the mean length on wild one-year-old muskies in the river is 13.5 inches, greater than the 6- to 7-inch length of the fingerlings stocked by the agency.
And that’s one reason why the stocked muskies aren’t surviving in the river.
“The wild fish are 10 inches by the end of August, and 14 to 16 inches by the end of October. The stocked fish are 6 to 7 inches by October, and muskies are known cannibals so when they are released and go to that nursery habitat, they’re being preyed upon by the larger muskies,” Wnuk said.
While natural reproduction will be the method of choice to sustain the muskie population in the North Branch, what will happen to the hatchery fish that were previously earmarked to be stocked in the river?
Wnuk said the muskie stocking program across the state is being revised and stocking rates will be cut.
But, he added, that decrease is designed to allow the hatcheries to produce bigger muskies to be stocked, a move that will help them survive. Considering that muskies are an apex predator that exists in low densities, Wnuk said it makes sense to cut stocking rates yet increase size.
“One reason why we want to stock bigger muskies is because of predation, particularly from bass,” Wnuk said. “The larger fish have a better chance, but if you stock them at too high of a rate they won’t grow above 30 inches. You have to give them space.”
Because the sampling was conducted in the spring, most of the fish captured on the river were males that instinctively wait at spawning areas for females to arrive. Wnuk said male muskies are smaller than females, yet his crew did capture a 44-inch female muskie in Northumberland.
Wnuk said there’s evidence that wild muskie populations increase following the termination of stocking, and both adult and young-of-the-year fish will be monitored throughout 2017. If the population unexpectedly decreases, he said, the agency can easily resume stocking to augment the fishery.
“It might take a few years for anglers to see the benefits of these changes, but I’m very impressed with the muskie population on the North Branch,” Wnuk said. “As far as Pennsylvania being a muskie state, I don’t think we’re on par yet with Minnesota, but we can get there.”