MILTON — On a gray April morning, with occasional snow flurries swirling, three fisheries specialists gathered on the Lamoille River to catch some of the river’s walleye for sampling.
This year, the Vermont Fish & Wildlife Department will do something it hasn’t done for more than two decades: stock walleye in the Lamoille.
The week prior, a similar group had set out to catch breeding pairs to bring back to the hatchery. There, staff can oversee the growth of fertilized eggs, raising the walleye to 5-millimeter fry and then 2-inch fingerlings before returning the fish to the river in the summer.
In the 1990s, more than a hundred cars used to sit parked along the Lamoille on walleye opening day, with anglers lining the river, hoping to catch and cook the native fish, according to Bernie Pientka, a fisheries biologist with Fish & Wildlife. Back then, a stocking program had helped revive the river’s walleyes, Pientka said. So the state stopped raising fish for the river, letting nature run its course.
But that positive trend gradually slowed. Now, angling pressure has dwindled — an indication, Pientka said, that the fish have dwindled, too.
“It was mostly recurring angler comments” that alerted biologists to the Lamoille’s struggling fishery, Pientka said.
In 2021, a survey of anglers estimated that on opening weekend, only one walleye was caught per 20 hours of fishing. In 1994, the peak catch rate was about 10 times higher on the Lamoille. The findings led state fisheries officials to conclude that “it may be time to carefully consider including Lamoille River in the Lake Champlain walleye stocking rotation.” This year, that program began.
The walleye, also called the yellow pike or yellow pickerel, is a freshwater fish native to most of Canada and the northern United States. It can grow to about 30 inches in length, weigh up to 20 pounds and, aficionados say, make a tasty meal.
Vermont already stocks walleye on a rotational basis in the Poultney, Missisquoi and Winooski rivers — all of which flow into Lake Champlain — every three years. Each river contains genetically distinct fish, Pientka explained, so the state harvests breeding pairs in each individual river, keeping the strains distinct. After transporting the fish to a hatchery, biologists care for the fertilized eggs as they grow into fingerlings.
When originally hatched, walleye are less than a centimeter, making them vulnerable to predation, Pientka said. Hardly able to swim, the newborn fish float higher in the river late at night, letting the current push them toward the lake before settling onto the river bottom during the day.
By letting the fish grow a couple of inches, biologists allow the fish to live out their most vulnerable stage in captivity. Transported back to their home waters a few months later, the fish have a much higher chance of survival. At that point, they’re already “little predators,” Pientka said, able to hunt for smaller fish.
But on this day, with the spring’s peak spawn already past, mostly males lingered upriver, hoping they might just get lucky once more.
Stunned fish
Pientka piloted a boat toward the Peterson Dam and the fast-moving water below it. As he worked toward a stretch of water below some small rapids, Dan DeLucia, a fisheries technician, served as his eyes.
“Rock 10 feet straight in front of you,” he called back to the captain in an effort to avoid bouncing the boat off the boulder. “We always go through a few propellers every spring.”
Two booms, adorned on their ends with a spider of wires, hung out over the front of the boat and draped into the water. When Pientka gave the signal, DeLucia stepped on a metal pedal on the boat’s bow, sending an electric pulse of five to seven amps into the water and stunning fish in the boat’s vicinity.
White and redhorse suckers floated in the current, temporarily incapacitated. Some, attempting to escape, shot out of the water in spasms. Other species mixed in, too. Hefty smallmouth bass, a couple of salmon, some pike, and a rainbow trout all appeared on the dreary April morning.
The walleye, a deep, earthy green and gold, all muscle with strong, wide tails, floated interspersed with the more prevalent suckers. Scooping with a long metal net, DeLucia plopped the fish into a holding tank in the center of the boat. In only a minute, they snapped out of their stupor, moving slowly in the 50-or-so-gallon tank.
With the boat steered to the riverside, Pientka, DeLucia and Dave Gibson, a fish specialist with Fish & Wildlife, got to work collecting data. Together, they measured and recorded sex, length and weight, as well as any diseases the fish might be carrying.
As Pientka explained, during mating season in the spring, the male walleyes swim around, waiting for females to arrive.
“It’s just like the bar,” DeLucia joked.
“The ladies come around 10 p.m.,” Gibson quipped.
Which fish were stocked?
Handling each walleye individually, Gibson scanned the fish for irregularities.
One of the fish contained a circular scar from a lamprey — a parasitic, jawless fish that latches onto its prey with its toothy mouth.
With every fish, Gibson carefully snipped a spine from its back using wire cutters, depositing the sample into little manila envelopes for further inspection. The spines contain rings that allow biologists to age the fish, he explained. By understanding the age distribution of the walleye population, scientists can better understand where in the fish’s life cycle it might be most vulnerable.
It was a dearth of young walleyes, Pientka said, that informed fisheries staff that the species needed extra care as fry, rather than angling pressure — which affects larger fish — being the cause of the decreased population.
Before distributing the hatchery-raised walleyes into the river, fish sit for six hours in a chemical dye. The dye, when put under a certain wavelength of light, glows. That way, when biologists later catch and observe the Lamoille’s fish, they know which fish were stocked and consequently how successful the stocking had been.
Come June or July, Pientka plans to return to the Lamoille, fingerling walleye in tow. Given time, he said, he hopes the state’s hand will bolster the river’s population. Walleye season opens the first Saturday in May, with fish 18 inches and over acceptable to harvest. If — or when — the walleye return in force, the anglers will, too.
