“Forevermore we are going to have to be hyper-vigilant. It came in once and it could come in again.”
—Grant Bogle, president of Twin Lakes Association
SALISBURY — An aggressive and costly three-year battle to rid East Twin Lake of a genetically unique strain of hydrilla that chokes lakes and obliterates native plants appears to have finally paid off.
“The good news is, the hydrilla is pretty much gone. We have not found anything,” George Knoecklein of Northeast Aquatic Research (NEAR), the Twin Lakes Association’s limnologist, reported during its fall coalition meeting of local, state and federal scientists, environmentalists and stakeholders on Tuesday, Oct. 8, at O’Hara’s Landing Marina.
The meeting’s location — several yards from where the first strand of the pernicious plant was discovered at the marina in May of 2022 and where a large sign now warns boaters of the threat — was a fitting backdrop for the 90-minute coalition meeting focused on managing the aquatic invader.
It is believed that the invasive weed, known as the Connecticut River Hydrilla, was introduced by hitching a ride with an unsuspecting boater.
Coalition partners included scientists and officials from the Connecticut Department of Energy and Environmental Protection (DEEP), the U.S. Army Corps of Engineers, local lake associations, town and state officials and other stakeholders.
Three years ago East Twin became the first lake to discover the novel Connecticut River strain of hydrilla in its waters. Since then, it has been identified in 10 additional state lakes.
Coalition member Gregory Bugbee, associate scientist at the Connecticut Agricultural Experiment Station’s Office of Aquatic Invasive Species (CAES/OAIS), reported that an effort to inspect all 84 boat ramps in Connecticut this year yielded only one site where hydrilla was found.
The threat nonetheless has lake associations rattled. Several groups from around the Northwest Corner have turned to the TLA and its coalition for guidance, as hydrilla — once established — is notoriously difficult to eradicate.
Herbicide’s impact
The meeting centered on this past summer’s success as well as collateral damage to a native plant, water marigold, following the TLA’s whole-lake treatment with the herbicide fluoridone.
Domenic Meringolo, environmental engineer and project manager with SOLitude Lake Management, said this summer’s treatment with Sonar, SePRO’s flagship aquatic solution, was more successful than prior spot treatments using the systemic herbicide ProcellaCOR.
While the ProcellaCOR failed to kill hydrilla, it was “beautifully effective” on ridding the lake of Eurasian watermilfoil, said Knoecklein. “It became pretty clear that the whack-a-mole strategy wasn’t going to work” on hydrilla.
The SOLitude project manager noted that the two-to-five parts per billion (ppb) concentration of fluoridone used throughout this summer at East Twin was to selectively control hydrilla while minimally affecting native aquatic plants at low concentration.
While the Sonar destroyed the hydrilla, it had an unintended ecological impact on one of the lake’s native aquatic species, Bidens beckii, commonly known as water marigold. The Bidens is a state protected plant that had been growing profusely in East Twin.
“This year, we couldn’t find it,” reported NEAR’S Knoecklein.
Of the 54 species of aquatic plants documented in East Twin Lake, the Bidens beckii was the only one adversely affected by the treatment, he explained. “We have more of it in Middle Twin, and there’s a very good indication that nothing else was impacted here.”
Knoecklein said he has been in contact with DEEP’s Natural Diversity Database (NDDB) regarding the loss of Bidens beckii.
“It was not completely unexpected, but we’ll be watching very closely next year,” he said. “I am hoping for some recovery.”
A diver is expected to re-inspect the lake this week.
“The hydrilla game has really become both surface visualization and looking for hydrilla in deeper waters,” said Knoecklein. “You can’t combat hydrilla in a lake without using these strategies.”
The TLA limnologist noted that prior dives found both young hydrilla plants and larger established ones.
“My suspicion is that this has been in the lake for four years and turned into a fort during that time, with massive plants six feet tall and lots of shoots. We had to move water lilies to find hydrilla growing under those plants.”
A sign warning boaters of the hydrilla threat at O’Hara’s Landing Marina stands in the location where the invasive weed was discovered at East Twin Lake in May of 2022. Debra A. Aleksinas
Lessons learned, lessons shared
The forum touched on the soaring costs of lake management, a concern to the TLA as well as smaller lake groups with limited funds and resources.
TLA’s annual lake management expenditures have increased tenfold — from about $50,000 per year to as much as $500,000 for the foreseeable future — as the association continues its intensive monitoring, testing, and prevention efforts.
Despite those costs, officials emphasized that East Twin’s experience offers valuable lessons for other lakes confronting hydrilla for the first time or preparing for an invasion.
Representatives from the Lake Wononscopomuc Association and Mt. Riga Inc., in Salisbury, attended the fall coalition meeting, along with officials from Mudge Pond Association in Sharon and Doolittle and Benedict Pond in northeastern Norfolk.
Christina Astrove, lake board president representing Doolittle and Benedict, was a first-time attendee. She was hoping to learn about how the TLA has been dealing with hydrilla and what steps are being taken to control and eradicate the worrisome weed.
While her lake community is private and prohibits motorboats, she is “very concerned” about the looming threat.
“I attended a Connecticut Federation of Lakes meeting this spring and have taken several webinars” on the topic, noted Astrove. “It’s scary.”
Mudge Pond representative Andrew Cahill said his group is bracing for hydrilla’s arrival due to high boat traffic.
“We have everything but hydrilla at this point, but I’m sure we will have it at some point.”
TLA President Grant Bogle said he is pleased to share information from lessons learned. “The goal is not only to support Twin Lakes, but to spread the word. It takes a village, literally, to address this threat.”
TLA officials said they have been fielding calls from lake associations throughout the United States seeking advice and guidance, and they are happy to share.
CAES’ Bugbee praised the Twin Lakes group’s aggressive response to the hydrilla threat, swift creation of its coalition of advisors and for sharing their collective knowledge. “This organization is second to none. It’s almost like a poster child for how things should be done.”
Knoecklein said despite vigilant surveillance of boat ramps and closing lakes off to the public, the hydrilla threat persists.
“In my opinion all possible vectors are on the table,” including recreational fishing and birds flying overhead dropping plant fragments.
Grant Bogle, TLA association president, agreed that “surveillance is key.”
“While we have good news to report in terms of hydrilla, this isn’t over. Forevermore we are going to have to be hyper-vigilant, no matter what happens down the road. It came in once and it could come in again.”
A mother bear and her cubs move through a backyard in northwest Connecticut, where residents told DEEP that bear litters are now appearing more frequently.
“We really want to hear from you,” said Justin Davis, DEEP’s bureau chief for natural resources, at the meeting. He said that DEEP is preparing a bear management report in early 2026 that evaluates the challenges the state is facing and the strategies going forward dealing with them. He said the report will include feedback from the public generated at the listening sessions. He urged attendees, however, not to turn the meeting into a discussion about whether there should be a hunt or not.
Davis called the return of black bears to Connecticut a “conservation success story,” but one that now comes with challenges. "They're large animals, they're powerful and they can become comfortable being around people--and they're opportunistic, and they love to eat."
DEEP shared data showing that black bears have been reported in nearly every Connecticut town and that conflicts involving trash, bird feeders, livestock and home entries have increased sharply in recent years. The state’s bear population was last estimated at roughly 1,100 to 1,200 animals, a number that DEEP recognizes has grown since the study was conducted in 2012.
Eric Hammering, the office director of Environmental Review & Strategic Initiatives at DEEP, told the attendees that since 2020 there have been 264 reported home entries in 38 municipalities in northwest Connecticut, citing data from the state's State of the Bears report released in March.
A home entry, he said, is defined as an event when a bear actually goes inside a resident's living space.
Attendees at the DEEP meeting in Sharon on Dec. 3By Christian Murray
DEEP officials stressed that bird feeders and unsecured household trash are the two biggest drivers of bear conflicts. They advise residents to remove feeders entirely and keep their garbage inside or in bear-resistant containers. DEEP representatives noted that once a bear discovers food, it is likely to develop habits and return.
Many attendees said they see widespread noncompliance in their neighborhoods — particularly among part-time residents and short-term rental guests who leave trash out for days. Several said they were frustrated that the people causing the problem are often not the ones who attend sessions like this.
As a result, a number of residents called for stronger statewide enforcement, including fines for leaving trash unsecured and penalties for repeated violations. Without consequences, they said, the same households will continue to attract bears and put neighbors at risk. Others described practical steps to reduce bear activity--including the use of secure dumpsters, food composting stations, and the placement of electric fencing around livestock and beehives.
Again and again, residents emphasized that the underlying issue is human behavior. One attendee summarized it succinctly: “There are 3.6 million people in Connecticut and far fewer bears. Human behavior is the problem.”
Lynn Levine, a Litchfield resident who enjoys seeing bears, said common sense steps are the answer. She said that when she first moved to the area, she mistakenly left her garage down open with a 15-pound bag of shelled peanuts inside. "A bear dragged the bag around the side of the garage, sat down and had a teddy bear picnic." She said she learned not to leave the garage door open, especially with food inside.
Not all the stories were lighthearted. An 82-year-old Sharon woman recounted repeated break-ins that left her shaken and facing thousands of dollars in repairs, including a bear walking into her kitchen while she was washing dishes. A veterinarian described livestock attacks, including an alpaca that was mauled and dragged. A farmer said bears caused about $160,000 in crop losses in one year and that cornfields across the region face similar damage.
Several speakers added that DEEP’s limited staffing means local police often end up responding when bears are struck by cars or behaving aggressively.
From the State of the Bears Report released March 2025CT DEEP
Cornwall First Selectman Gordon Ridgway, who attended the session, said afterward that he was troubled by how outdated the state’s population data is.
“My biggest personal take-away was surprise — that DEEP doesn’t have a handle on how many bears are here,” he said. “They said they haven’t surveyed them since 2012. How do you make a plan or policy without doing a survey?”
Ridgway said Cornwall has received about 40 bear-related reports this year, including home and vehicle entries and injuries to pets. “People are frightened by intrusions onto their property,” he said. “These are not happy stories.”
He noted that in 2012 -- when the state said it last did its population count -- “a bear was a novelty,” but sightings today are very common. “Today, most people see a bear every week. It’s no longer a novelty — it’s a real issue.”
Ridgway said he supports developing a statewide management plan and wants Connecticut to examine approaches used in other states, including reducing their numbers.
While most attendees at the Dec. 3 session indicated they opposed a hunt, Ridgway said that is not a true reflection of how his constituents in Cornwall view the issue. “If we had a vote, it would be close as to whether there should be a hunting season.”
Only one attendee — a longtime hunter from West Cornwall — advocated for a controlled bear hunt. He argued that the population is “exploding” and that education and bear-proof containers are “a band-aid.” In keeping with DEEP’s rules, other residents did not respond, and the session took place without conflict.
Much of the remaining discussion centered on unsecured trash, short-term rentals, and outdated dumpsters at state parks that residents say train bears to expect human food. Some questioned why the listening session was not better publicized, and Ridgway echoed that concern, saying it should have also been held at the high school to allow more residents to attend.
DEEP collected comment cards at the end of the session. Staff said all feedback will be reviewed as the agency drafts its statewide bear management report.
