Tag Archives: Lake Champlain

A fish points to the future in Lake Champlain

This is the final installment in a five-part series that follows an Atlantic salmon on its journey upstream to spawn in a tributary of Lake Champlain driven by its instincts (and a pickup truck). Learn why this species disappeared from the lake in the 19th century, and how it is making a comeback today thanks to collaboration by partners in the basin.

“Clinton County New York has a seal, and there is a fish on that seal,” noted Bill Wellman, a Board Member for the Lake Champlain Chapter of Trout Unlimited. “That fish is a salmon.”


In salmon we trust: The official seal for New York’s Clinton County, which borders Lake Champlain, bears a familiar fish.

Wellman, whose organization has been instrumental in supporting all aspects of salmon restoration in the basin, explained that two hundred years ago, salmon would have been a logical choice for the emblem of a county that abuts the lake. “They were so prevalent in these rivers that people could just wade into the middle of a stream and catch them with a pitchfork,” he said.

Although native Atlantic salmon disappeared from the lake in the late 1800s, the restoration effort has gradually reintroduced new generations of this species to the streams where its ancestors once spawned, and the communities they once symbolized. The proof is in the parking lots.

“When salmon are running in the spring and fall, you will see cars with license plates from all over the Eastern United States and Canadian Provinces,” he said. “There is an obvious economic benefit that goes along with this fish.”


For communities in the Lake Champlain Basin, salmon are both a cultural icon, and a natural asset. Credit: E. Peter Steenstra/FWS

In rural communities with relatively little industrial development, it’s a valuable natural asset. Last December, the nonprofit Boquet River Association invited the supervisors and public works superintendents from the five towns that border the river in Essex County New York to meet for an update on the development of a comprehensive management plan for the watershed.

“We went through all of the planning activities, and then I brought up the issue of salmon restoration, and the importance of a fishery to economic development,” said Vic Putnam, the retired planning director for Essex County New York who serves on the association’s Board of Directors.

Given that most of those in attendance also happened to be fishermen, Putnam knew salmon would be the perfect bait. “They readily perceived it as a good thing,” he said. “Everyone wants to work together to promote water quality so we can re-establish the salmon fishery.”

But Putnam knew the plan would also appeal to them as municipal agents, and members of the community.

“We are really trying to support town needs, whether that’s for flood-zone management, erosion control, riparian restoration, recreation, training employees, sewer and septic upgrades, monitoring and assessment, salt contamination…”

The list went on. It seems communities need a lot of help to address a variety of different issues that can impact both ground and surface water, and salmon are both a motivator and an indicator. They are an effective way to attract anglers, writers, and funding to the Boquet and other tributaries of Lake Champlain, but they are also a way to measure progress in improving the overall health of a watershed that many other species depend upon.

“Salmon have a lot of notoriety, and there is a strong following among fishermen, but I am excited to see how other species respond,” said Putnam. “Certain kinds of minnows, white suckers — they are also tuned into the river environment at specific times of year. It’s about the ecosystem in its entirety, not one fish alone.”


The return of salmon to tributaries like the Boquet River indicates progress for this species and others that make their home in the Lake Champlain Basin. Including people. Credit: Bridget Macdonald/FWS

I guess that means this story isn’t really about one fish either. After all, the different partners that have played a vital role in the salmon restoration effort didn’t just come together because of salmon; they came together because they share a geography and a stake in its future.

The final installment in the series was supposed to be about salmon habitat restoration, but it turns out none of the habitat restoration work led by the Service in the Lake Champlain Basin is explicitly focused on salmon. Rather, it’s about sustaining the surrounding landscape and communities.

“We work on projects that have a holistic focus,” said Chris Smith, Supervisory Fish and Wildlife Biologist at the Lake Champlain Fish and Wildlife Conservation Office. “When we do a culvert restoration, a dam removal, or plant trees on a stream bank, it benefits salmon and numerous other native species, but communities also benefit from greater flood resilience.”

Improved flood resilience means less damage associated with flooding, which will amount to significant financial savings for town, state, and federal government agencies. That cost benefit creates important buy-in for work in which every acre counts. “Riparian restoration is one of the tools that you gives you maximum bang for your buck: it addresses bank erosion, overland flow, nutrient inputs, and provides habitat benefits.”

It’s also a great way to involve the community. Smith oversees the Partners for Fish and Wildlife Program in Vermont, which focuses on the restoration of wetlands, woodlands, and riparian areas through voluntary actions by private landowners, watershed organizations, and non-profits. “It’s hard to engage the public in a hands-on way for a dam removal or culvert replacement,” he said. “We can’t have the public run heavy equipment, but we can have them plant trees.”


Volunteers plant trees along the Winooski River in Marshfield, Vt. Credit: Katie Kain/FWS

Can they ever. The nonprofit group Friends of the Winooski plants about 1,500 to 2,000 trees every year in efforts to benefit the Winooski River watershed, many of which are done in partnership with FWS. Project manager Shawn White gave an example a project completed recently in the headwaters of the Winooski in Cabot, Vt. “We identified a property with no buffer at all, that turned out to be a hayfield, so we reached out to the landowner and he decided he could spare some land that didn’t have to be hayed,” she said. “It turned into a three-acre restoration.”

Partners Program staff member Katie Kain, a Fish and Wildlife Biologist for the Service, emphasized that in Vermont, a small state with a rich agricultural heritage, agricultural producers are key partners in conservation.

“We do a lot of our work with farming communities through USDA programs where farmers voluntarily agree to give up their riparian areas for habitat restoration in exchange for annual rental payments,” she said, adding, “Just getting one farm in the area to come around to looking at their land management from a different perspective makes a difference.”

Kain pointed to a project completed last year in partnership with the Vermont Land Trust, the Vermont Agency of Agriculture, and the USDA Farm Service Agency to convert seven acres of farmland along the banks of the lower Winooski River into a forested riparian buffer.

“Because there are dams upstream, the Winooski in this section is what you would call a ‘hungry river’: It’s starved for sediment, it’s starved for wood inputs, so there is not much going on for habitat right now,” she explained. Over time, having trees back on the river bank will provide both shading, and a source of insects and woody debris that offer in-stream habitat benefits for salmon.


A new fence keeps livestock out of a riparian buffer at Dalestead Farm in Vermont. Credit: Katie Kain/FWS

In terms of water quality benefits for wildlife and people, she said, “We’ve already reduced the agricultural runoff into the river by convincing one farm that had been applying manure right up to the riverbank to step back.”

Riparian restoration helps reduce the non-point source inputs of phosphorus and sediments into the lake and its tributaries, which is particularly important in Vermont. The U.S. Environmental Protection Agency recently released new phosphorus pollution limits for Lake Champlain by establishing Total Maximum Daily Loads for twelve Vermont segments of Lake Champlain.

Conservation partners including the U.S. Fish and Wildlife Service, USDA’s Farm Service Agency and Natural Resources Conservation Service, Vermont Agency of Agriculture, Vermont Department of Environmental Conservation, The Nature Conservancy, the Intervale Center,  and Lake Champlain Basin Program, are working together to identify places and approaches that are both a priority for reducing phosphorus inputs and for enhancing fish and wildlife habitat while supporting farms and sustainable agriculture. Not just to benefit Atlantic salmon, but also Eastern brook trout, Monarch butterfly, migratory birds, Indiana bat, wood turtle, and more.

It’s clear the partnership is thinking about the big picture, but I admit I’m still thinking about my salmon. When I visited the Boquet River last fall, Senior Fish Scientist for the Service’s Lake Champlain Fish and Wildlife Conservation Office Bill Ardren told me, “A lot of things need to be right for salmon to have a full life cycle.”

And every week, I heard from different partners who are working to address historic wrongs in an effort to give this species a second chance in the basin, through dam removal, tactical control of a parasitic species, managing around an invasive species, refining hatchery production, dispensing vitamins, and of course, instituting a public transportation system for salmon, like mine, who need a lift.

To be sure, there is more work to be done, and more partners to enlist. For example, a budding effort by the Service and partners to assess potential spawning and rearing habitat in the watershed through a combination of habitat stream surveys and models that predict which tributary watersheds and stream reaches have the right characteristics for rearing and spawning. Characteristics like gravel size, water depth, velocity, and temperature.

But while the prospects for my salmon remain uncertain (at least at the time of publication) the outlook for the species seems increasingly clear.

“Dam removal, sea lamprey control, habitat restoration — all of that is now in place,” said Ardren. “We are getting big salmon back, they are digging their nests, they are providing a fishery again, and providing a connection for people in the local communities to return to the rivers.”


Senior Fish Scientist Bill Ardren from the Lake Champlain Fish and Wildlife Conservation Office talks with local fishermen on the banks of the Boquet River in Willsboro, N.Y. Credit: Nancy Milliken

After all, the recovery of salmon signifies more than just a comeback for fish. “These fish helped sustain the people who settled this valley,” said Putnam. “They are part of our history.”

And the reestablishment of the salmon population in the lake is itself history in the making.

In the book Lake Champlain: A Natural History, naturalist Mike Winslow observed, “The lake does not reflect today’s actions so much as yesterday’s.” If tomorrow’s lake reflects the actions partners are taking today, I have a feeling there will be plenty of salmon swimming beneath the surface.

Taking cues from nature to advance salmon restoration

This is the fourth feature in a five-part series that follows an Atlantic salmon on its journey upstream to spawn in a tributary of Lake Champlain driven by its instincts (and a pickup truck). Learn why this species disappeared from the lake in the 19th century, and how it is making a comeback today thanks to collaboration by partners in the basin.

“I want you to see this structure out here because it has really informed our thinking about the effects of barriers on fish movement,” said U.S. Geological Survey Research Ecologist Theodore Castro-Santos as we walked across the snow-covered grounds of the Silvio O. Conte Anadromous Fish Research Center in Turners Falls, Mass., to check out what appeared to be a swimming pool connected to a long cylinder wrapped in plastic.

“This is the Aquatic Biomechanics and Kinematic Research Station. We call it ABiKiS.”


USGS Research Ecologist Theodore Castro-Santos with ABiKiS, one of several structures used by scientists at the Silvio O. Conte Anadromous Fish Research Center to learn how fish respond to barriers.

Although ABiKiS was battened down for the winter, Castro-Santos helped me picture what it would look like in action. “Imagine this is something like a culvert,” he said of the cylinder. “We introduce fish into the tank, feed in lots of water, and then drive flows through the system at different velocities.”

Then they just wait, and watch. For what? Initially, the researchers intended to use ABiKiS to study the biomechanics of swimming — how fish move — to figure out how to design structures that would be easier for them to navigate. But something else caught their attention during the trials. Regardless of their swimming ability, it took some fish much longer to enter the culvert than others. That is, if they entered at all. “We realized that when designing these structures, we had to consider motivation: Not just what can fish do, but what do fish do?”

This evolving understanding of fish behavior and physiology is helping partners advance a long-term goal for salmon restoration in the Lake Champlain Basin. “We are reemphasizing the recolonization of rivers by natural populations in all of our management decisions,” said Bill Ardren, Senior Fish Biologist for the Lake Champlain Fish and Wildlife Conservation Office.


This flexible facility at the Conte Anadromous Fish Research Station in Turners Fall, Mass., allows researchers to study how fish respond, or don’t respond, to different passage scenarios.

As such, the research in Turners Falls using ABiKiS and several other structures has offered valuable perspective on the conditions salmon need to succeed in Lake Champlain. Castro-Santos worked with graduate student Daniel Nyqvist from Karlstad University in Sweden to apply the movement theory informed by simulations to a real problem with downstream passage in the Winooski River in Vermont.

While adult salmon migrating up the Winooski to reproduce in the fall have had assistance reaching spawning habitat thanks to the collaborative “Trap and Truck” program, it appears juvenile salmon attempting to migrate out to the lake in the spring are not getting the help they need to navigate the series of three dams on the river.

“One third of the fish in our study failed to pass the first dam they encounter going downstream from their spawning areas — Essex 19 — and those that did pass spent weeks trying,” said Castro-Santos. Why? In part, they lacked motivation — literally, a reason to move.

“If you put a dam across a river, it stops the flow of current, and fish no longer have the natural cue to keep swimming,” he explained. More than just an inconvenience, this loss of momentum can be life changing. When a migratory fish encounters a barrier that it cannot pass safely, it will actually lose the physiological mechanisms that compel it to swim downstream in the first place. In other words, said Castro-Santos, “They stop being migrants.”


Hydraulic Engineer Brett Towler inspects the bypass at the Essex 19 dam after research indicated fish were having difficulties navigating the fishway.

Or, they get eaten by a predator that takes advantage of the salmon bottleneck. Either way, not what the salmon had in mind. Or the scientists.

“What we found following Ted’s study was that there were a number fish-passage issues with the existing facility,” said Brett Towler, a Hydraulic Engineer for the Service who crawled inside the dam’s intake area in the wake of the findings to take a closer look at the bypass. Towler provided the operator Green Mountain Power with recommendations for improvement, and the company is currently considering implementing some or all of them to help them achieve Low Impact Hydropower Certification for the dam.

To be fair, Towler pointed out that the problem has only surfaced because the salmon restoration program is seeing such strong returns. But that’s all the more reason to redouble fish passage efforts on the Winooski and other rivers. “The ability for smolts to migrate out is incredibly important to the natural life cycle of salmon.”

And enabling salmon to complete their natural life cycles is incredibly important for all aspects of a program focused on recolonization. Including in hatcheries. Ardren said that about six years ago, program managers started to wonder: “Would small changes in the way the fish were cultured increase the numbers that returned to rivers on their own?”

They decided to experiment with switching the water supply for half of the raceways at the Dwight D. Eisenhower National Fish Hatchery from well water to water from nearby Furnace Brook.


All of the salmon at the Dwight D. Eisenhower National Fish Hatchery are now raised in water supplied by Furnace Brook, rather than in well water.

While the well-water raised salmon, which were kept a comfortable 50 degrees Fahrenheit, continued to eat and grow throughout the winter, the brook-water raised salmon were literally frozen in time. “They were stuck at the size they had been in the fall,” said Ardren, explaining that in the dead of winter, Furnace Brook is a relatively “low energy” system. “Bridget, you could play hockey on it.”

After one year, all of the fish, big and small, were stocked in the Boquet and Winooski Rivers at the “smolt” stage, when salmon naturally want to swim downstream into the lake, to feed.



Salmon at the parr stage (top), compared with salmon at the smolt stage (bottom), when they experience the physiological changes that cue them to swim downstream.

After three years, when the experimental program ended, Ardren said, “We were surprised to find that the return rate of fish raised in brook water was three to five times higher than the return rate of fish raised in well water, even though the well-water raised fish were much larger when released.”

Scientists believe the smolt stage is also when imprinting occurs, enabling salmon to find their way back to their natal streams years later when it’s time to spawn. In a river, the bacteria and biofilms on rocks give off chemical cues that a salmon can key into. In well water, there’s no biofilm to speak of, which is good for drinking, but not so much for imprinting.

It seems fish that grow up in a more natural brook-water environment head out into the wild with their olfactory senses calibrated to recognize a river so they know where to go when nature calls. The finding was so strong, that now all of the fish at Eisenhower are raised in water from Furnace Brook, including my fish. She was stocked as a smolt in the Boquet River primed to imprint, and sure enough, found her way back there when it was time to reproduce. My fish may have needed a ride to get to the spawning grounds, but she didn’t need directions.

With each new finding, scientists are developing a better picture of the salmon life cycle, but there’s still the big picture. No matter how much we know about the cues that nature gives salmon to swim downstream to feed, or upstream to spawn, the long-term success of the salmon in the lake and its tributaries depends upon what happens on the surrounding landscape.

During my visit to the fish research station in Turners Falls, Castro-Santos made an observation about the shift in conservation priorities from individual species, to entire systems: “People often think about salmon when they think about fishways and fish passage, but the focus is now moving toward passing entire communities, not just salmon.”

I know he meant aquatic communities, but metaphorically, the idea goes beyond the river. My salmon passed a major obstacle in the Boquet thanks to partners who care about its future. In order for my salmon’s offspring to have a future in Lake Champlain, the restoration program has to address barriers for communities too.

And it is. Learn how next week, in the final installment.

Hatching a plan to save salmon


Assistant hatchery manager Scott Frost explains the research behind these trays of larval salmon at the White River National Fish Hatchery.  Photo: Bridget Macdonald/FWS

This is the third feature in a five-part series that follows an Atlantic salmon on its journey upstream to spawn in a tributary of Lake Champlain driven by its instincts (and a pickup truck). Learn why this species disappeared from the lake in the 19th century, and how it is making a comeback today thanks to collaboration by partners in the basin.

“You have to step on this footpad to come in and out of this area,” cautioned Scott Frost as we crossed into a roped-off section of the White River National Fish Hatchery. “It has a disinfectant to make sure we don’t drag any contaminants in on our boots.”

Once our boots were clean, Frost, who is the assistant hatchery manager, led me over a row of rectangular structures and rolled up a black curtain to reveal racks of trays alternately labeled with plus and minus signs. Each tray contained hundreds of recently hatched larval salmon.

“These eggs were spawned from fish caught migrating from the lake to spawn in Hatchery Brook last fall,” he said. “We incubate the eggs until they get to the ‘eyed’ stage, where you can see the eyes inside the eggs,” he explained. “They are very fragile up to that stage.”

When I visited, the eyes had appeared, but the young salmon still warranted special treatment. They weren’t just stock for the lake; they were research subjects.

“They are all from the same parents, but half of them have been treated with Vitamin B1, and half of them have not,” he explained. “We are trying to determine if treatment is effective in stopping the Thiamine deficiency problem.” Hence the labels, and the precautions.


Larval salmon in the “eyed” stage of development. Yes, that means they have eyes. Photo: Bridget Macdonald/FWS

The study at White River is just one of many research projects being undertaken by partners in the Lake Champlain Basin to get a handle on a growing challenge for the collective effort to restore salmon: alewife.

Quick recap: Introduced in 2003, alewife gradually crowded out rainbow smelt, the primary native food source for salmon, and salmon began eating alewife instead. That’s bad because alewife carry an enzyme called Thiaminase that digests the Vitamin B1 inside salmon, which suffer the consequences of losing an essential compound used to metabolize energy. For perspective, a deficiency of Vitamin B1 in humans leads to a disease called beriberi that interferes with the nervous system and causes heart failure.

For Lake Champlain salmon, the Vitamin B1 deficiency seems to be interfering with the entire reproductive cycle. It is known to make eggs inviable and inhibit the development of juveniles, and it may be interfering even earlier in the process by having physiological impacts on adults.

This week we’ll look at a snapshot of the research taking place in the basin to ensure that salmon have a future in the face of a threat that is likely here to stay. “We’ll never get rid of alewife,” said U.S. Fish and Wildlife Service Fish Biologist Nicholas Staats. “We just have to manage around them.”

So how do you manage around a problem that affects salmon throughout its life cycle? You start by assessing it at every stage.

Adult Swim


Concordia University graduate student Andrew Harbicht prepares to release a salmon into the Boquet River after giving it an injection of Vitamin B1. Or was it a placebo? Photo: Bill Ardren/FWS

The question: In 2014, Concordia University doctoral student Andrew Harbicht noticed that very few salmon were being tallied at the counting station at the fish ladder in the Willsboro Dam (which was removed the following year) even though fishermen in the Boquet River were seeing large numbers of salmon in the pool at the base of cascades below the dam.

“We knew fish were in the river, but they weren’t making it up the rapids: Is that because they couldn’t?” he asked. “Since we know the Thiaminase can cause motor dysfunction among juveniles, we wondered if it might be affecting adults too.”

The approach: Harbicht and his colleagues set up a trap about a mile downriver from the cascades to intercept salmon on their way upstream. They gave half of them an injection of saltwater and Vitamin B1, and the other half a placebo injection of salt water.

Before the researchers released the fish back into the river to continue their upstream migration, they tagged them with transponders that could be detected by a series of six antennae set up at different points within the cascades to monitor their progress. In other words, the salmon were being timed.

Who won? It appears that the treated fish took much less time to reach the top of the rapids, compared to untreated fish, and that they spent less time in the pools within the rapids before continuing their ascent. Although Harbicht cautioned that the results are only preliminary, the study suggests that the Vitamin B1 deficiency is keeping adults from performing their best. “Either because they are less motivated, or need more time to recover.”

The implications: The findings could support a short-term workaround for the alewife problem: Vitamin B doping. “If we can strategically intercept fish as they enter tributaries, not only will it help adults reach stream habitat, it puts Vitamin B in their system that they can pass down to their offspring, giving them a better chance of survival.”

Scrambled Eggs 

The question: Although scientists have been finding lots of salmon nests, called redds, in rivers in the fall, they have not been finding as many juveniles emerging in the spring as would be expected. Bill Ardren, Senior Fish Scientist for the Lake Champlain Fish and Wildlife Conservation Office,said that has led to them to wonder: “Is it due to a lack of Vitamin B1 in the eggs, or is due to the quality of the habitat?”


There are ten of these egg boxes, and one scientist, in the photo below. Can you see them?


The approach: This fall scientists collected eggs from adult salmon migrating from the lake during spawning season to serve as the research cohort for a study on Vitamin B1 deficiency, much like those Frost showed me at the White River hatchery. Except that after the Vitamin B1 treatment was applied (or not applied) to these eggs, they were returned to the wild.

Concordia University graduate students Nicole Hill and Ashlee Prevost constructed artificial redds in the Winooski River and Huntington River and placed the eggs in boxes to track their survival. “The eggs are incubating right now,” said Ardren. Who will survive? Tune in this spring to find out.

The implications: The findings could confirm suspicions. If none of the eggs hatch, it’s possible habitat conditions are to blame. If only the treated eggs hatch, all signs point to Thiaminase.

It Runs in the Family 

The question: As reported last week, scientists found a natural-born salmon fry in the Winooski River last summer for the first time in 200 years. “That gives us hope that at least there are some females out there that did have enough Vitamin B1 to pass onto their offspring for them to survive,” said Ardren. “We want to know: Are some fish through natural selection, or some other means, able to combat this enzyme?”


Purdue University graduate student Avril Harder tends to her research subjects: salmon eggs. Photo: Bill Ardren/FWS

The approach: Graduate student Avril Harder from Purdue University is conducting a genetic study looking at the response of different salmon families to Thiaminase. “She is taking eggs from the same salmon families that Nicole and Ashlee planted in the wild, rearing the eggs in tanks on a Thiaminase diet, and looking at response that different families have to the deficiency,” explained Ardren. It may be that some families are more tolerant to Thiaminase, giving them the ability to digest and still maintain good Vitamin B1 levels.

The implications: The findings could be game changing. Let me back up a bit. Last fall, scientists took eggs from salmon caught returning from Lake Champlain to Hatchery Brook at Vermont’s Ed Weed Fish Culture Station and transported them to White River Hatchery. Some of those eggs are the research subjects that Frost showed me when I visited the hatchery. The rest of them represent an exciting new future for the Lake Champlain salmon restoration effort.

How so? First, it’s important to know a little more about where these eggs came from. The Ed Weed hatchery is located on the shores of Lake Champlain in the town of Grand Isle, Vt. Salmon are reared in water from the lake which drains out of the hatchery in a man-made brook. When young salmon at Ed Weed become “smolts” — the developmental stage when hormonal changes cue them to migrate to the lake to feed — they are released to the lake.

Guess where these salmon will turn up in about a year and a half when hormonal changes cue them to migrate back upstream to spawn. Hatchery Brook, where the water from the hatchery where they were raised drains into the lake.

The salmon that return to Ed Weed thus are prime specimens for breeding: We know they have what it takes to survive in the lake, and we know their homing ability is spot on. Not to mention, they’re easy targets. Check out this footage of salmon crowding into the brook in 2015. It’s like natural selection on demand.

“The idea is to produce eggs from salmon that have adapted to the lake and shown themselves to be successful in returning to their natal stream,” said Frost. “We will grow those eggs all the way to mature adults that are ready to spawn, and those salmon will be become the production fish for stocking the lake.”

What does have to do with the project at Purdue? If scientists can identify salmon families that are genetically equipped to resist Thiaminase, they can fortify the broodstock by selecting eggs from those parents.

“We have done a lot of work in the hatchery program to improve on the quality of fish across the basin, looking at differences in water temperature regimes, growth rates, and timing of stocking,” said Henry Bouchard, manager of the Dwight D. Eisenhower National Fish Hatchery, where my salmon was born. “Now there may be opportunity for us to use wild eggs to develop a broodstock that is more tolerant to the alewife situation.”


Dan Wong (FWS), Tom Chairvolottie (Vermont), and Henry Bouchard (FWS), spawning a salmon at the Ed Weed Fish Culture Station in Grand Isle, Vt. Photo: Bill Ardren/FWS

You can probably see where this is going: Future generations of salmon raised in hatcheries to have a natural resistance to Thiaminase are stocked in the Boquet River at the smolt stage, and then swim out into the lake to mature, and when nature beckons them to spawn, they will have the endurance and/or motivation to ascend the cascades, find the pristine spawning grounds, and pass on those desirable genes to their offspring.

And that may have implications beyond Lake Champlain: a salmon that is resistant to Thiaminase could provide a new strain to support conservation of at-risk landlocked salmon populations in other systems, like Lake Ontario, where alewife have also become a problem.

But there’s still work to be done to make sure this system can support future generations of salmon partners hope to see returning to natal streams on their own. For one, ensuring that the streams they return to are in good enough condition for them to spawn. It might help to figure out exactly what leads salmon back to these streams in the first place. My salmon is evidence that we are making progress on that front. Learn why next time.