In January 2025, over 90 critically endangered North Atlantic right whales congregated on Jeffrey's Ledge, prompting Maine lobstermen to take voluntary measures — including lowering endlines — to reduce entanglement risk. Researchers led by Camille Ross improved habitat models by adding prey (Calanus) data, which increased predicted whale density for November through January. Strong cooperation between fishers and scientists, supported by programs like NOAA’s Study Fleet, helped prevent entanglements and points to better prediction and communication systems going forward.
Maine Lobstermen and Scientists Unite to Protect 90+ Critically Endangered Right Whales
North Atlantic right whales sometimes gather at Jeffrey’s Ledge, a 62-mile-long underwater ridge about 25 miles off the coast of Portsmouth, New Hampshire.
On a cold, windy week in January 2025, more than 90 critically endangered North Atlantic right whales (Eubalaena glacialis) unexpectedly gathered on Jeffrey's Ledge — a 62-mile-long underwater ridge roughly 25 miles off Portsmouth, New Hampshire. The unusual aggregation forced Maine lobstermen to leave traps in the water and prompted rapid, cooperative action between fishers and scientists to lower entanglement risks and improve future early-warning systems.
A Rapid, Voluntary Response
After confirming they had followed all state and federal rules — using breakaway ropes, extending trawls to reduce vertical endlines, and marking gear with purple tracers — local lobstermen held an emergency meeting. Acting voluntarily and against routine practice, fishermen lowered their northeast endlines to reduce the number of vertical ropes in the water. That simple but swift measure, combined with communication among crews, helped ensure the whales remained unharmed that month.
Illustration of how North Atlantic right whales get entangled in fishing gear. Entangled whales sometimes tow fishing gear for hundreds of miles.Image: WHOI Graphic Services, Woods Hole Oceanographic Institution via NOAA.
“We had to do something more to lower the risk. No fisherman wants to harm a right whale, so we’re willing to bend over backwards to make this work,” said lobsterman Chris Welch.
Science Improves Prediction
Researchers led by Camille Ross and colleagues at the New England Aquarium, Bigelow Laboratory for Ocean Sciences, Duke University, and the University of Maine published a study in Endangered Species Research that shows how including prey data — specifically krill-like zooplankton in the genus Calanus — improves habitat models for right whales. Calanus are tiny, rice-grain-sized animals whose distribution is highly sensitive to small changes in ocean temperature. As the ocean warms and currents shift, the prey moves, and the whales follow.
By incorporating prey-location data, the team found increased predicted right whale density on Jeffrey's Ledge from November through January — information that, had it been available and communicated in advance, could have alerted fishermen to heightened risk and allowed them to take precautionary measures earlier.
A North Atlantic right whale mother and calf as seen from a research drone called a hexacopter. Hexacopters allow researchers to conduct right whale photo identification and photogrammetry studies. Photogrammetry techniques allow scientists to get body measurements from aerial photographs.Image: NOAA Northeast Fisheries Science Center/Lisa Conger and Elizabeth Josephson.
Why This Matters
The North Atlantic right whale population is precariously small — roughly 380 individuals with about 70 reproductively active females — so every avoided injury or death is critical to the species' survival. In January 2025, because of concern, communication, and cooperation, zero entanglements were reported on Jeffrey's Ledge.
Communication Gaps and Collaborative Solutions
Despite the successful outcome, communication remains fragile. Fishermen relied on an informal phone chain to spread the alert because the state lacked a quick group-text or alert system for on-the-water crews. Programs such as NOAA’s Cooperative Research in the Northeast and the Study Fleet demonstrate effective scientist–fisher collaboration: commercial fishers collect environmental and fishery data that improve models and management decisions.
Ross and her team plan to refine models by using more recent, year-to-year prey and whale sighting data so predictions become timelier and more actionable for managers and fishers as the ocean continues to change.
Takeaway
The Jeffrey's Ledge event illustrates how stewardship by working fishers, improved scientific models that include prey dynamics, and better communication systems together can reduce risk to endangered whales. It also highlights a roadmap: integrate recent ecological data into predictive tools and establish rapid alert channels so fishers can make informed, voluntary choices to protect marine life while maintaining livelihoods.
Help us improve.
