For Immediate Release:
Environmental DNA (eDNA) Analysis Confirms the Presence of Shortnose Sturgeon in the Connecticut River Between Turners Falls MA and Bellows Falls VT
[Aug 29, 2024, Alstead, NH/Greenfield, MA] An ongoing investigation led by the Connecticut River Conservancy (CRC) has for the first time detected DNA from the endangered shortnose sturgeon (Acipenser brevirostrum) in the Connecticut River between Turners Falls, MA, and Bellows Falls, VT/Walpole, NH. The study was initiated by CRC’s River Steward for New Hampshire, Dr. Kate Buckman, in partnership with James Garner, a PhD candidate at the University of Massachusetts with expertise in environmental DNA (eDNA) techniques.
In this investigation, CRC used existing research by Micah Kieffer, a sturgeon biologist at the USGS Eastern Ecological Science Center S.O Conte Research Laboratory, as well as information from Annette Spaulding of Rockingham, VT, and Joseph Graveline of Northfield, MA, regarding sturgeon behavior and previous sightings of this rare fish. This helped Buckman and Garner narrow down the stretches of river to target for eDNA sampling. Critical to the sampling efforts was the involvement of numerous volunteers who provided field support to conduct the work. The first round of samples was collected in June and July, with positive “hits” detected in water collected in Northfield, MA, Vernon, VT, and Westmoreland, NH.
Shortnose sturgeon are a federally endangered species, and it is illegal to intentionally target, catch, or disturb them. Historically, shortnose sturgeon would have been found throughout the Connecticut River watershed as far north as Turners Falls, and possibly as far north as Bellows Falls. However, the presence of numerous dams on the mainstem, habitat degradation, and commercial fishing have negatively impacted populations of this fish, as they have for many native migratory species.
“While a breeding population of shortnose sturgeon is known to exist downstream of Turners Falls, from a regulatory standpoint, shortnose sturgeon do not exist upstream of there,” noted Dr. Buckman. “Community members have reported anecdotal sturgeon sightings in New Hampshire and Vermont waters, but to date, only two of those observations have ever been verified in photographs,” continued Dr. Buckman. “This means that management actions to protect the species and their habitat have not been implemented north of the Turners Falls dam. These initial eDNA results are the first hard evidence supporting these anecdotal observations and are an important step in ensuring that shortnose sturgeon receive the protection they deserve in the more northern reaches of the Connecticut River.”
UMass Amherst PhD Candidate James Garner adds, “Our results demonstrate that there are detectable levels of shortnose sturgeon DNA at multiple locations within the reaches of the Connecticut River upstream of the Turners Falls and Vernon dams. The strength of the hits relative to our positive controls signals to me that these endangered fish are present throughout these upstream reaches, but likely at lower numbers than where they exist farther south. This collaborative project demonstrates the power of a wonderful team and a well-designed use of eDNA techniques for the monitoring and conservation of endangered species.”
eDNA techniques are particularly useful in detecting rare species, as they require less intensive time and people investments than traditional netting or fishing efforts. Put simply, if a fish is active in a water body, it is shedding genetic material contained in slime, excrement, scales, etc. That DNA is collected as part of a water sample which is filtered, and the DNA extracted from the material retained on the filter. Special probes that are designed to bind only to DNA from the species of interest (in this case shortnose sturgeon) are used in a reaction called qPCR that amplifies the targeted DNA strand and makes multiple copies of it. How quickly the copies accumulate in the reaction can be measured and the strength of the signal correlates with how much DNA was initially present in the water. Lots of fish lead to lots of DNA and a very early (strong) signal in the qPCR reaction.
Image captions: #1: James Garner hands a collected water sample to a colleague on the boat. Photo credit Kate Buckman. #2: James Garner works in Dr. Jeremy Andersen’s insect lab at UMass Amherst to extract DNA from filters. A fish-free space is ideal for keeping low concentration samples uncontaminated. Photo credit Kate Buckman. #3: Dr. Kate Buckman uses a YSI to collect water quality data at a sample site while volunteer boat support Julian Burgoff looks on. Photo credit James Garner.
“It is still remarkable to me that using this technique we can detect sturgeon DNA in a river the size of the Connecticut River by sampling only two liters of water, but we can, and we did,” says Dr. Buckman. Equally important is ensuring that the ecology of the species of interest is considered when designing a sampling strategy. Shortnose sturgeon are typically benthic fish, so Buckman and Garner focused their efforts on sampling water from the bottom of the river, something that was not done in an eDNA survey six years ago with no positive hits.
What remains unknown is how the shortnose sturgeon got above Turners Falls, given the prevalence of dams on the Connecticut River since the 1800s, or how long the fish have been there. There are many possible routes through which sturgeon could have accessed these upper reaches, but Buckman and Garner are content to let that remain a mystery. For now, providing preliminary but compelling evidence that shortnose sturgeon are there is exciting enough.
Sampling efforts will continue over the fall and winter. While the positive results from water samples taken earlier this summer indicate shortnose sturgeon presence in the Connecticut River in Vermont, New Hampshire, and Massachusetts waters upstream of Turners Falls dam, additional positive hits throughout the year will provide even more robust evidence that these fish are living north of Turners Falls year-round. “I am extremely grateful for James’ enthusiasm and knowledge in implementing this project, as well as to our funders and volunteers. The work we have done so far and what we plan to continue doing would not be possible without their support,” Dr. Buckman added.
This ongoing work was funded by generous grants to the Connecticut River Conservancy from the Lucy Downing Nisbet Charitable Fund, Bank of America, N.A., Co-Trustee and the Jack and Dorothy Byrne Foundation. Lucy Downing Nisbet Charitable Fund provided funding that allowed for planning discussions and project design, purchasing supplies, and the initiation of field sampling and qPCR analysis. This and additional support from the Jack and Dorothy Byrne Foundation will allow for the continuation of the sampling and analysis efforts into 2025.
For additional Information please contact:
Kate Buckman
River Steward, NH
Connecticut River Conservancy
603-931-2448
Diana Chaplin
Director of Communications
Connecticut River Conservancy
413-834-0079
James Garner
PhD Candidate
UMass Amherst
Environmental Conservation Department (ECO)