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- New Hampshire Restoration Project Manager | ctriver.org
< Back New Hampshire Restoration Project Manager Classification: Full-time, salaried, exempt Deadline to apply: Applications are now closed, the deadline to apply for this position was January 2nd, 2026 Start Date: Flexible Office Location: Fully remote, preferably based in New Hampshire Health benefit eligible: Yes Retirement benefits eligible: Yes Supervisor: Stream Restoration Specialist Starting Salary Range: $55,000 - $70,000 Position Description The Connecticut River Conservancy (CRC) restores and advocates for clean water, healthy habitats, and resilient communities to support a diverse and thriving watershed. Through collaborative partnerships in New Hampshire, Vermont, Massachusetts, and Connecticut, CRC leads and supports science-based efforts for natural and life-filled rivers from source to sea. The primary focus of this role is to provide project management and technical expertise to develop and complete stream restoration projects in New Hampshire under CRC’s 5-year funding program through USDA NRCS (with other projects likely as grant funding becomes available). Restoration projects can include streambank bio-stabilizations, dam removals, floodplain restorations, riparian buffer plantings, aquatic habitat improvements, and culvert/road crossing upgrades. This position will be responsible for maintaining a portfolio of grants to support their restoration work in New Hampshire. This position will report to the Stream Restoration Specialist (based in New Hampshire), and work with the CRC Restoration Program team, the Director of Programs, and the Grants Strategist. This position is remote with travel as required for CRC staff meetings throughout the watershed, as well as site visits, project implementation and overnights in NH. Restoration Activities Oversee the development, design, permitting, implementation, contracting, and funding for restoration projects, with a focus on projects in NH under the NRCS RCPP 3446 award. Can manage other non-RCPP projects as time and funding allows. Project management duties include, but not limited to, working with NRCS NH to plan and implement restoration projects according to NRCS standards, contracting engineering firms and subcontractors, reviewing permits, managing grant budgets, coordinating with project partners (including agencies like NHDES, NHFGD, USFWS, and NRCS), assisting with annual reporting, and maintaining internal and external project databases. Act as a landowner liaison for potential and on-going restoration projects. Be on-site and conduct daily construction oversight activities during the construction phase of your projects. Participate in regular CRC Restoration Program meetings to review current projects, strategize about potential new projects, and coordinate field season needs and staff coverage. Assist with annual grant reporting and maintaining online platform(s), as needed. Outreach Activities Conduct outreach with local advisory committees, conservation commissions, town, state, and federal officials, and other NGO partners to share information on CRC restoration efforts and the RCPP funded work. Use outreach outcomes to develop a list of priority restoration projects. Work with the CRC communications team to share the story and impact of our restoration work. Direct Reports No direct reports. However, this position will be overseeing external consultants. Qualifications We are dedicated to building a diverse, inclusive, and authentic workplace. We understand that many folks who may be impacted by biased hiring standards, such as women, individuals with disabilities, LGBTQIA+ and BIPOC applicants, may only apply if they meet every requirement listed in a job posting. If you are interested in this opportunity and believe you meet most of the job requirements, we encourage you to apply. Postgraduate or Bachelor’s degree in the natural resources field (ecology, biology, geology, hydrology, environmental engineering, etc.) Demonstrated experience working effectively both as part of a team as well as independently. Ability to be on a project site Monday-Friday for multiple weeks in a row for construction oversight, including being outside during summer months. Excellent written and verbal communication skills, and organizational skills. Passion for ecological restoration. Commitment to equity and inclusion. Previous experience managing restoration projects, including contracting, permitting, engineering design review, construction oversight and public outreach. Demonstrated ability to communicate effectively and professionally with a diverse group of partners, stakeholders, funders, and members of the public. Experience with grants, including writing, managing, and final reporting. Ability to do work in-stream, including navigating pools, ledges and rocky areas Ability to lift up to 25 lbs. Salary and Benefits The starting salary range for this position is $55,000 – 70,000. CRC provides a comprehensive benefits package. The New Hampshire Restoration Project Manager position will be a hybrid position located remotely working from your home office in or near NH with project-related site visits and meetings across Coos, Grafton, Sullivan and Cheshire counties. Applicants must be able to travel within the Connecticut River watershed and regularly attend staff meetings and regional events. Some overnights will likely be required. Application instructions To apply for the position, use the form below. Please name the file with your first and last name. Deadline to apply January 2nd, 2026 Overview of the Organization The Connecticut River Conservancy (CRC) restores and advocates for clean water, healthy habitats, and resilient communities to support a diverse and thriving watershed. CRC has been a steward of the Connecticut River and its tributary streams since 1952. Our programs include advocacy, aquatic invasive species management, dam removal, habitat restoration, migratory fish surveys, recreation, trash cleanups, and water quality monitoring. Through collaborative partnerships in New Hampshire, Vermont, Massachusetts, and Connecticut, CRC leads and supports efforts for resilient and life-filled rivers from source to sea. We are uniquely positioned to leverage local, state, regional, and federal resources as the only science-based nonprofit working throughout the entire watershed. Our values of inclusion, collaboration, resilience, and stewardship guide our ongoing work to address the climate crisis, biodiversity loss, and pollution. Together through community engagement and education, we’re helping to ensure healthy rivers for all. Learn more at ctriver.org . Connecticut River Conservancy is an Equal Employment Opportunity and Affirmative Action Employer and will engage in an inclusive recruiting and hiring process. It considers all applicants for employment without regard to race, color, religion, sex, sexual orientation, national origin, age, disability, veteran status, or any other characteristic protected by state or federal law. Apply Now First name Last name Email Phone Applying for Choose an option How did you hear about this job? Please upload your resume and cover letter as a single PDF file. 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- Events | Connecticut River Conservancy
The Connecticut River Conservancy restores and advocates for clean water, healthy habitats, and resilient communities to support a diverse and thriving watershed. Upcoming Events CRC's events bring the people to the river and the river to the people! Join us to learn, connect, and engage with all that the watershed has to offer. Events may be virtual or in-person and are added throughout the year. Upcoming events are listed below. You can also sign up for email updates to hear about new events as they are scheduled, and view our library of LiveStream recordings. No events at the moment Event Calendar View January 2026 Today Sun Mon Tue Wed Thu Fri Sat 28 29 30 31 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 1 2 3 4 5 6 7 For questions about CRC's events, or to recommend future events, contact Stacey at slennard - at - ctriver.org.
- Connecticut River Conservancy
The Connecticut River Conservancy restores and advocates for clean water, healthy habitats, and resilient communities to support a diverse and thriving watershed. We protect, restore, and advocate for the Connecticut River Our Mission Get to Know Our Mission, Vision, & Values Upcoming Events Register to Learn & Connect Get Involved Volunteer, Participate, or Donate Connecticut River Conservancy is a 501(c)(3) nonprofit organization dedicated to the Connecticut River watershed in New Hampshire, Vermont, Massachusetts, and Connecticut. We collaborate with regional partners to restore and advocate for your rivers, and educate and engage communities. We bring people together to prevent pollution, improve habitat, and promote enjoyment of the river and its tributary streams. Join us to support healthier rivers today! Clean Water Through advocacy to prevent pollution and water quality monitoring to track data. Healthy Habitats Through dam removal, tree planting, and migratory fish programs. Resilient Communities With river recreation access, community science, & Source to Sea Cleanups. Our Mission & Programs Sign Up for River News! Sign up to get emails about river news and events. Choose Your Newsletter Watershed Snapshots Photo Raffle Learn More 1,182 Tons of trash removed from rivers 32 Old dams & culverts removed 100K+ Trees planted in the watershed 150+ Sites annually tested for bacteria No Simple Swim: The Mysterious Migration of the American Eel (Anguilla rostrata) Tracking the migratory life cycle, obstacles, and research related to American eel in the Connecticut River watershed. Action Alert: OPPOSE the Proposed Rule Change for Waters of the United States This rule change would reduce protections for wetlands, vernal pools, and other waterbodies with groundwater connections—all of which are abundant in the Connecticut River watershed and important for flood resiliency and aquatic habitat. Currents at the Conservancy: 2025 River Highlights LiveStream This end-of-year livestream highlighted the significant accomplishments achieved throughout the Connecticut River watershed in 2025. River Stories from Around the Watershed Latest News More River News We envision a future where people and wildlife can enjoy a clean, free-flowing Connecticut River. Upcoming Events No events at the moment Learn About: Migratory Fish Migratory fish are essential to healthy river ecosystems. The Connecticut River hosts 8 species of migratory fish that travel thousands of ocean miles and over 200 miles upriver annually. CRC's migratory fish restoration efforts include advocating for and expanding fish passage and raising awareness through community science and education. Learn More
Events (171)
- July 10, 2024 | 8:30 PMNorth Thetford, Thetford, VT, USA
- July 16, 2024 | 8:30 PMPerkins Landing Rd, Littleton, NH 03561, USA
- August 4, 2023 | 1:30 PM82 French King Hwy, Gill, MA 01354, USA
Blog Posts (134)
- No Simple Swim: Tracking a Complicated Year for Migratory Fish (Sea Lamprey & American Shad)
Sea Lamprey in the Saxtons River, a tributary of the Connecticut River, in June 2025 by Jill DeVito. When CRC Aquatic Ecologist Dr. Kate Buckman led a sea lamprey nest survey of the Ashuelot River in southern New Hampshire toward the end of July 2025, she explained to the gathered volunteers and CRC staff that the cobble constructions she had seen in Massachusetts tributaries were not quite up to the lamprey’s typical building standard. Beyond that, she had seen lampreys still spawning during the late June and early July surveys—which were intended to happen after the nesting season. Our group of community scientists didn’t end up seeing any live lampreys, as it turned out, that day on the Ashuelot. But we found very few freshly built nests compared to previous years, and that made us curious. Was 2025 a “bad year” for sea lampreys in the Connecticut River Valley? If so, why might that be? And how did other migratory fish species fare? The answer, it turns out, is pretty complex. So I asked Ken Sprankle, the USFWS Connecticut River Fish and Wildlife Conservation Office project leader, to help tease apart what happened this spring and early summer. Ken compiles the fish counts reported at each of a dozen fishways designed to allow passage beyond hydro dams on the main stem and major tributaries of the Connecticut River. And he noted that overall, 2025 was actually a pretty good year for our migratory fish. But there were a few exceptions (including the sea lamprey), so we’ll come back to that later. Spring 2025 Was Cold and Wet The region experienced abundant rainfall during key points in the spring migration season, which decreased water temperature and increased river flow levels. As Lael Will, a Fisheries Biologist at the Vermont Fish and Wildlife Department, explains, “This is not a bad thing for fish, as water, and cold water are a good thing as opposed to drought years.” Ken Sprankle agrees that a cold, wet spring like this one may prolong the nesting season, which might even help some migratory species. This year, for example, American shad had a pretty good run. Better Than Average For American Shad More than 324,000 American shad passed through the Holyoke Fish Lift in 2025. That may not come close to last year’s banner year over 437,500, but it’s above the long-term average of 320,500 over the past four decades. Those that made it all the way into New Hampshire and Vermont started passing through the Vernon fishway in the middle of May, about a week later than they did last year. We’re looking forward to finding out how many fish ultimately made it past the Vernon Hydro Dam, where the count is still being tallied for shad—as well as for the sea lamprey we searched for in the annual CRC lamprey nest surveys. A Strange Year For Sea Lamprey Last year in the Ashuelot, CRC volunteers tallied over 150 lamprey nests, including multiple large community nests. Kate reports that while she is still finalizing the data, this year’s excursion resulted in far fewer, with a preliminary estimate of just over 20 that could be confidently identified as new nests. “Based on our observations of late, messy nests in the MA and CT rivers we survey annually, as well as the reduced number of nests in NH, I am curious as to whether the spring rains and higher flows delayed lamprey enough that they were running out of energy and just didn’t travel as far, or if there were just a lot less lamprey in this year’s migration.” says Kate, “Passage numbers and dates can help tease out some of those year to year patterns as well.” Fewer than 16,700 sea lamprey were counted at the Holyoke fish lift this year. That’s roughly half the long-term average of almost 32,000, and it’s a dramatic drop from last year’s remarkable total over 53,600. So what’s going on here? We’re not quite sure. One thing we do know is the lampreys that made it past the Vernon fishway arrived about two weeks later than they did in 2024. Lael Will notes that “when we have high flows,” it can be “harder for the fish to find the entrance to the ladder.” But she also points out that “sea lamprey numbers are highly variable and can be influenced by both instream and ocean conditions as well as how the fish ladders perform under varying flows.” Ocean studies of sea lamprey are few and far between, but the population size in a given year may be influenced at least as much by other factors (for example, the availability of host fish species they feed on in the ocean) as by the conditions in the river when they head upstream to spawn. Not only that, but the lampreys that start their lives in the Connecticut River might end up spawning anywhere else along the Atlantic Coast of North America; and in turn, the lampreys that come here to spawn each year could have been hatched in any other East Coast watershed, making predictions of yearly returns more challenging. Sea lamprey building a nest below the Wiley-Russell Dam in Greenfield, MA. To Be Continued A large number of ecological factors influence the population size of each generation of a migratory species – from the condition of juvenile habitat to the availability of food in the ocean, to the obstacles we humans throw into their path. In fact, it’s worth noting the same hydro dams that make the upstream (and for some species, downstream) river passage more challenging for our migratory fish provide us with the best opportunity for counting them as they funnel through each fishway. So we take advantage of this opportunity to keep our finger on the pulse of migratory populations. And we’ll be back with more information about how our other migratory species fared this year – the alewife herring, blueback herring, American eel, and shortnose sturgeon. This article was the first in a series related to documenting 2025 fish migration in the Connecticut River. You can also read the second article about alewife and blueback herring or the third about American eel.
- No Simple Swim: Tracking Population Declines in Alewife and Blueback River Herring
Ken Sprankle and his team at the U.S. Fish and Wildlife Service track river herring through electrofishing surveys, otolith age analysis, and scale collection. Video by Alix Kaplan. Meet the alewife and the blueback herring–but don’t feel bad if you have trouble telling these two species apart. The alewife typically has a bigger eye relative to its body size, but even an expert can’t confirm a species identification without cutting the fish open. And these two have a lot more in common than their looks. Together known as “river herring,” the alewife and blueback were once spectacularly abundant here in the Connecticut River watershed. They both spend most of their lives in the Atlantic ocean, and they each got their start in a river. Alewife (top) and blueback herring at the Connecticut River Fish & Wildlife Conservation Office (photo by Jill DeVito). You may be familiar with other anadromous fish—like sea lampreys and many species of salmon, which migrate to the ocean as juveniles and swim upstream as adults to spawn. River herring are anadromous too; but unlike the sea lamprey, alewife and blueback herring can survive the upstream spawning journey and swim back downstream. Ideally, a river herring in the prime of its life will return to its saltwater habitat after laying or fertilizing eggs. This round trip is too exhausting for an individual fish to complete every year—but it might return to spawn twice or even three times over the course of its life. In fact, in healthy populations of alewife or blueback, many adults should be doing just that. But here in the Connecticut River, river herring populations are imperiled. Not many fish are making it back from the ocean to spawn, and only a tiny fraction of those have made the journey more than once. Like our other migratory species, they are challenged by obstacles like hydro dams and habitat degradation in river systems. But alewife and blueback herring may be in even greater danger from the human-made hazards they face in the ocean. Ken Sprankle and his team at the USFWS Connecticut River Fish and Wildlife Conservation Office, along with other members of the Connecticut River Migratory Fish Restoration Cooperative, are trying to help change that. A Terrible Year for Blueback Herring I was curious how the river herring had fared during this year’s migration in the Connecticut River, so I turned to Ken Sprankle for help with understanding their situation. Ken compiles annual fish count reports from hydro dam passage facilities to keep track of how many individuals of each species are coming through each fishway on their way upstream. But river herring populations are in such precipitous decline here, he says the fish passage counts “are not really informative to us anymore.” For example, this year only 144 blueback herring passed through the Holyoke Fish Lift. Thirty-five years ago (before the sudden collapse of the commercial river herring fishery in southern New England), Holyoke passed around 400,000 bluebacks in a typical spring. And alewife herring have not passed through Holyoke at all in recent decades. Both species are “functionally extirpated” from that part of their historic range; they’re just not making it that far upriver anymore. 2025 Electrofishing research expedition in Wethersfield Cove (photo by Alix Kaplan). Fortunately, Ken Sprankle has another way to track the river herring populations. His team spends most of each spring out on the water, using an electrofishing boat to survey for migrating alewife and blueback herring on major tributaries in the southern portion of the Connecticut River valley. But Ken reports that 2025 was not a great year for these fish. “My blueback herring catch rate across all monitored sites in 2025 was higher than the 12-year low of our program last year, but still well below the same time period mean rate. We also sample alewife but at much lower levels; approximately 15% of our sample data is comprised of alewife. Given the lower sample sizes, inferences are more difficult to make." Blueback herring fishing success rate per minute of electrofishing effort has been low in recent years (courtesy of Ken Sprankle, Connecticut River Fish and Wildlife Conservation Office.) How Many, and How Old? To understand how a population is doing, the first thing a biologist wants to measure is abundance over time. How many herring made the migration each year compared to previous years? It takes a lot of work to gather this type of data over the long term. Researchers need to get past year-to-year fluctuations to identify a trend of growth or decline. But this work is crucial to help inform fisheries management decisions and potential restoration measures. Ken’s team has been sampling for twelve years now. And when they calculate the number of blueback herring captured relative to their sampling effort (how much time is spent trying to catch the fish), they find that in the past few sampling seasons their catch rate has been low. That picture could be complicated by high river levels resulting from heavy spring rains in recent years, because it’s harder to find fish in a larger volume of water. But the team has other clues they can use to solve the mystery of what’s happening with the herring. These clues are hiding in the bodies of the sampled fish. Ear bones (right) are used to determine the age of sampled river herring (photos by Alix Kaplan). Beyond tracking how many fish swim upriver each year, the key to understanding the future of a population is to reveal its age structure. In other words, Ken’s team needs to know how many of these fish are coming upriver for the first time, and how many have survived to make the journey more than once. So how does a scientist measure the age of a herring? “To do that,” Ken says, “we need to extract bones out of their skulls.” The sampled fish are put on ice and brought back to the lab. There, a researcher removes two tiny, flat, Pac-Man shaped ear bones from each fish and prepares them for analysis under a microscope. These ear bones are called otoliths, and—much like a tree—they contain growth rings that can be counted to reveal how many seasons the fish survived. That’s how we know that most of Ken’s sampled fish are young. About 60% of the blueback herring collected in his study are age four or younger, and fewer than 7% are at least seven years old. Ken says the maximum life span of a river herring is about fifteen years, but his team doesn’t catch fish older than ten. The age structure of this population is concerning because older, larger female river herring often lay more eggs than younger females. The super survivors are the ones with the greatest potential to help grow the population. And these days, in our region they’re not living long enough to do that. Ken Sprankle leads an electrofishing expedition on the Farmington River in 2023 (photo by Jill DeVito). Deadly Encounters with Ocean Fisheries It’s been almost twenty years since the Atlantic States Marine Fisheries Commission (ASMFC) banned commercial and recreational fishing for river herring in southern New England. And in the intervening years, habitat restoration projects have made the Connecticut River watershed a safer place for fish to swim and spawn. So why haven’t these stocks recovered? As it turns out, river herring appear to be coming up against the greatest obstacle to their survival in the habitat where they spend most of their lives: the ocean. While alewife and blueback herring are no longer targeted by fishing operations, they are still captured accidentally by nets intended for other fish. And they rarely survive the experience. The Atlantic States Marine Fisheries Commission acknowledges that bycatch is a serious problem for river herring populations that are already severely depleted, and the New England Fisheries Management Council had proposed a now paused amendment process to help address this issue in our region (See the Connecticut River Conservancy's 2024 comments on the amendment here ). So, based on their own studies along with data collected by fisheries, members of the Connecticut River Migratory Fish Restoration Cooperative are advocating for new regulations in the southern New England fishery. These would include stricter limits on bycatch, and increased monitoring efforts to enforce them. They also recommend fishing prohibitions in specific areas during certain times of year. And they have reason to hope such efforts will succeed, because similar measures have helped restore river herring stocks in Maine. "These two species are resilient and have responded well to restoration measures under the right set of conditions,” Ken says. “As resource managers we are trying to better define limiting factors that are difficult to study in the marine environment.” Dr. Kate Buckman, Aquatic Ecologist at the Connecticut River Conservancy, is hopeful too. “River herring play important ecological, economic, and social roles in our watershed, and we’d like to see those roles regain the prominence they historically had. The work of the Cooperative is critical to understanding what is impeding river herring population recovery. I’m hopeful that the time-series data in the river, combined with knowledge of what they are facing in other ecosystems, will lead to effective management changes that enhance survival and spawning success for these beautiful fish.” This article was the second in a series related to documenting 2025 fish migration in the Connecticut River. You can also read the first article about sea lamprey and American shad or the third about American eel.
- No Simple Swim: The Mysterious Migration of the American Eel (Anguilla rostrata)
An American eel ( Anguilla rostrata ). Photo by Kayt Jonsson/USFWS. A Storybook Sleuth on a Slippery Trail When I learned that 6,481 juvenile American eels had passed through the eel ramps at the Holyoke Dam fishway in 2025, I wanted to understand what that meant for the Connecticut River population. It seemed like a straightforward question, but the more I learned about eels, the more I started to feel like a storybook sleuth on a slippery trail. For starters, there are not many fishes more elusive than the American eel. You might very well have eels in a river near you, but they’re hiding under cover during the day and hunting at night, so you’re not likely to meet one. When I finally tracked one down at an aquarium exhibit, I looked into her huge blue eyes—and I found it really hard to look away. American eel (silver phase) at ECHO Leahy Center for Lake Champlain (photo by Jill DeVito). This individual was a silver phase eel—an adult American eel at the final stage of its epic life cycle. The sinuous body of a silver eel has changed from yellow-brown to mostly gray. And its eyes have grown from ordinary size to enormous, in preparation for navigating the dark ocean depths ahead on its harrowing journey. If this one were swimming in a river instead of a tank, she would be on her way downstream toward the Sargasso Sea in search of the mysterious place where the life of every American eel begins (and the life of the hardiest and luckiest among them will end). Illustration by Salvor Gissurardottir via WikiMedia Commons. The Sargasso Sea is a two million square mile swath of the eastern North Atlantic Ocean bounded by ocean currents rather than land. Scientists have been unable to identify the exact spawning location of the American eel (or that of its close cousin, the European eel, which also spawns there) despite more than a century of searching the Sargasso Sea. What we do know is that both of these species are catadromous – that’s the opposite of the anadromous life cycle you may be familiar with in salmon, sea lamprey , and other migratory fishes that spawn in rivers and grow large in the ocean. Instead, catadromous species like the American eel spawn in marine systems and migrate to fresh water to feed and grow for the majority of their life. When eel eggs hatch in the Sargasso Sea, the resulting larvae are tiny, transparent, and flat (think: flat like an angelfish rather than flat like a stingray ). They are called leptocephali, and they drift on ocean currents and feed on the organic particles they encounter there, until finally their bodies take on a more familiar tubular, eel-like shape. These “glass eels” are still nearly transparent, but they’re large enough to swim toward their next destination. For the American eel, that could be an estuary or river mouth anywhere from Guyana to Greenland. Glass eels photos by Creative Commons. When it reaches coastal habitat and begins to feed, it takes on a brownish body color; the now-earthworm-sized eel is called an elver. In places like the Connecticut River system, juvenile eels will make their way upstream in search of the slow-moving, soft-bottomed habitats where they’ll grow for years (or sometimes decades) as “yellow eels” before their transformation to the reproductively mature and migratory silver phase. Onward and Upward (the Upstream Obstacle Course) As you might imagine, eels face challenges to their survival at every turn along this vast migration route. If a larval eel survives running the gauntlet of predators and other hazards (such as climate change altering conditions and productivity) in the open ocean, it may gather with other glass eels on their way toward a river mouth. At this point, they are vulnerable to commercial harvesting for human consumption. Locally, the Atlantic States Marine Fisheries Commission has measured dramatic declines in glass eel stocks. As a result, they’ve banned fishing for this life stage in all New England states except for Maine (but even there, quotas have been reduced in recent years). The eels that make it into freshwater as elvers won’t just be swimming against the current; they’ll find their path obstructed by dams of all sizes. These one-to-three-year-old juveniles are surprisingly good climbers, so they’ll crawl over smaller dams on warm, wet nights from spring through fall. Sooner or later, though, they’ll come to a substantial barrier like the Holyoke Dam where those 6,481 elvers were counted this year. So how do these very small fish find their way to the other side of a very big dam? A few juvenile eels somehow wriggle around or climb over large dams without help; and they may swim through fish ladders and lifts designed for other species. But for elvers to pass upstream in significant numbers, a barrier must be fitted with ramps for eels to climb. The climbing ramps come in many designs, but in general imagine a Rube Goldberg style pegboard made of rubber and tilted like a ramp; the elvers wind their bodies around the pegs and slither over. From there they fall into a tank (the “trap”) where they can be counted before being released upstream of the dam. Left: a ramp designed to help eels over barriers like dams. Center: a juvenile eel climbs a wetted ramp. Right: Alex Haro works with American eel in the lab (source: Alex Haro, US Geological Survey). You can’t see these eel ramps as a visitor to the public viewing areas at the Holyoke fishway, so I asked an eel expert for help understanding them. Dr. Alex Haro is a scientist emeritus at the USGS Conte Anadromous Fish Research Laboratory in Turners Falls, Massachusetts. And he’s enthusiastic about sharing what he’s learned over the course of more than forty years spent studying his favorite “forgotten fish.” About twenty years ago, Alex was involved with the complicated process of trying to figure out how to pass elvers effectively at Holyoke. Finally, after almost a decade of improving the functionality of the ramps and figuring out the best places to put them, the facility passed up to 50,000 elvers in a single year. Annual American eel ramp/trap counts reported by Holyoke Gas and Electric, at Holyoke Dam, for the period 2003-2024 (Ken Sprankle, US Fish and Wildlife Service Connecticut River Fish and Wildlife Conservation Office). Fish biologists like Alex hoped the number of elvers passed at Holyoke would continue to trend upward over time, leading to a healthy population of yellow eels growing large in the northern portion of the Connecticut River system—and the potential for an increasing number of silvers to make their way back to the ocean. But the upstream passage counts over the past decade have fluctuated from year to year in a trend that has been generally downward. A low count year could result from local flooding events that force a temporary shutdown of the passage facility. Or there could be fewer elvers arriving at the dam due to environmental factors that affect larvae and glass eels in the ocean, before they enter the river. Even year to year variation in Atlantic Ocean currents can affect larval survival—or it could simply redirect larvae to other river systems across the Eastern Seaboard. One thing Alex Haro is careful to explain is that the annual fish count at Holyoke only tells us how many eels passed the dam . We don’t know how many showed up below the dam trying to make it upstream in the first place because to determine that would require a “massive mark recapture study over five to ten years.” In science speak, massive translates to labor intensive and expensive. Finding funding and multi-year commitments for science research is generally difficult; it’s even harder when the study is massive and the subject is a forgotten fish . Until then, we just won’t know what proportion of the juvenile population is able to make it north of Holyoke, or the subsequent barriers at Turners Falls/Great Falls, Vernon, Bellows Falls, Wilder, and onwards. Historically, American eel were found all the way to the Connecticut Lakes in northern NH, but getting there now requires a much more challenging journey, often without dedicated eel ramps like those at Holyoke. Yellow phase American eel spend five to fifteen years growing larger in freshwater habitats like the Connecticut River (source: Ken Sprankle, US Fish and Wildlife Service). Double Jeopardy (the Downstream Obstacle Course) Once they’ve taken up residence in the Connecticut River and its tributaries, yellow eels will spend roughly five to twenty years foraging and growing; sometimes reaching lengths of more than three feet. But their biggest challenge may still be ahead of them. Eels that have made it this far in life don’t face as many dangers as they did when they were young but they won’t contribute to the future population unless they transform into silver eels and find their way back to the Sargasso Sea. To do this, first, they have to pass through every barrier they climbed as juveniles again ; this time in the downstream direction. At Holyoke, Alex Haro explains, there are several routes they can take. A silver eel may spill over the dam (at Holyoke, that’s a thirty-foot drop). A plunge pool at the foot of the dam increases the chances that a fish will survive the fall. Or an eel may pass through the intake to the spinning turbines that generate power. Since this has the potential to result in injury or death, some facilities (like Holyoke) have reduced the spacing between bars intended to prevent large objects and animals from being sucked into the turbines. But some eels still manage to wriggle between the bars, putting them at risk. Finally, an eel that finds its way into the adjacent Holyoke power canal may be diverted through a special downstream fish bypass, away from the intakes of several smaller turbine units that draw water from the canal. From the bypass eels are transported via a pipe to the pool below the dam and released to continue their journey downstream. The Hidden Life of a Forgotten Fish Alex Haro explains that there’s no single program in place for collecting eels throughout the watershed to study how many there are (or how fast they grow, or even where they live). “Counting all of them or even developing an accurate habitat-wide estimate is virtually impossible because there’s so much habitat.” At present, eels occupy virtually all the freshwater habitat in Connecticut, the mainstem and larger tributaries in Massachusetts, and the mainstem and lower portions of the larger tributaries in Vermont and New Hampshire, a total area of about 4,000 to 6,000 square miles. As a result, he’s had to be creative about using the upstream elver count at Holyoke to predict how many yellow eels are swimming around the northern portion of the watershed, and how many of those will turn into departing silvers like the ones that can be sampled at the power canal filter. He's produced a model that incorporates the Holyoke passage counts with survivorship information from other eel populations where scientists have documented how many elvers make it to adulthood. Using the model, Alex estimates there are 50,000 eels upstream of Holyoke. At 25 eels per square mile across 2,000 square miles of occupied habitat, that’s quite a low density for a fish that was once abundant. One thing that improves the accuracy of this population model is knowing at what age our local eels are coming and going at Holyoke. Alex has gleaned some of that information from the otoliths (ear bones) of elver and silver specimens collected at the fishway in past years. But wait, how does a scientist figure out the age of an eel from ear bones? I recently visited the USFWS Connecticut River Fish and Wildlife Conservation Office to find out. Dr. Corey Eddy, a fish biologist, explained that his more recent collection of elver and silver specimens from Holyoke would beef up the data set Alex Haro is using in his model. “You know how you can cut a tree to see how old it is? We can do the same thing with otoliths.” Because, like trees, fish ear bones have annual growth rings. First, however, the ear bones extracted from each specimen need to be prepared for viewing under a microscope—and this is a painstaking task. Fortunately, the project is able to move forward with the help of a local volunteer through Veterans Affairs named John McLaurin. John has taken over the processing of the otoliths; first he embeds them in epoxy resin, then he cuts a thin section to mount on a microscope slide. Finally, he adds a blue stain that makes the rings more visible. Then he’s ready to estimate the age that eel had reached when it was collected at the dam. USFWS biologist Corey Eddy (left) and volunteer John McLaurin, Jr. (right) count microscopic growth rings on ear bones to estimate age in American eels (photos by Jill DeVito). “We’re aging American eel,” Corey explains, “so we can begin to understand the relationship between age and size. We’re going to take that data and give it to Alex so he can put it into his population assessment model, which will give us an estimate of how many American eel there are above the Holyoke Dam.” This should help scientists use future annual counts at Holyoke to estimate the total eel population above the dam, so they can make more informed management decisions, including improving passage at upstream dams. “Today there are substantially more barriers to American eel migration than in pre-colonial times," notes Kate Buckman, the Connecticut River Conservancy's Aquatic Ecologist. "There is dedicated upstream eel passage at Holyoke, but between Holyoke and the Connecticut Lakes there are ten hydroelectric dams on the mainstem, none of which have passage facilities designed for eels. The research being conducted helps us to better understand how many eels there are, where they are, and what they are doing currently. Yet impediments to habitat access will continue to negatively impact survival and reproduction, and prevent us from reaching population targets outlined in management goals. Working to require the installation of both upstream and downstream eel passage is a critical component of rebuilding the population of American eel in the Connecticut River and something that both CRC and the Connecticut River Migratory Fish Restoration Cooperative are actively addressing.” I, for one, would love to see people care enough about the fate of the American eel to advocate for its conservation. But I’ve learned firsthand that inspiring affection for this forgotten fish can be a challenge. When I told a family member they might have eels in the small river that runs behind her backyard (fully expecting her to be delighted), her response was “eew.” As Alex Haro points out, “They’re slimy, they’re ugly, and nobody around here eats them, so why should we care about them?” American eels are a vital keystone species that enhance aquatic ecosystems, act as a crucial link in nutrient cycling between oceans and freshwaters, and provide food for predators such as birds and otters. “Appreciating eels isn’t hard once you know more about them,” says Alex. Perhaps, after learning more about the epic adventure that is the life of the American eel, you might agree? This article was the third in a series related to documenting 2025 fish migration in the Connecticut River. You can also read the first article about sea lamprey and American shad , or the second about alewife and blueback herring.







