Fall waterfowl migration at the Hinsdale Setbacks

As autumn settles across the Monadnock Region and temperatures begin to fall, an annual migration is unfolding along the Connecticut River. Ducks, geese and other waterfowl are making their way south, stopping along wetlands and waterways to rest and feed before continuing toward their wintering grounds. Among the region's most notable destinations for these migrating birds is the Hinsdale Setbacks, a sprawling stretch of open water and marshland along the Connecticut River that has become one of New Hampshire's premier inland birdwatching locations. On Sunday, Nov. 8, the Harris Center for Conservation Education and the Monadnock Bird and Nature Club will lead a guided waterfowl walk through the area, offering participants an opportunity to observe the seasonal migration and learn more about the birds that travel through southwestern New Hampshire each fall. For Phil Brown, bird conservation director at the Harris Center, migration is part of a much larger natural cycle that connects the Monadnock Region to ecosystems across North America. "Waterfowl consists of ducks, geese, and swans," Brown explained. "Generally, there are several dozen species in North America, and many of those have occurred at the Hinsdale setbacks over the years." Many of these birds are temporary visitors, stopping in the northeast as they travel between breeding grounds farther north and wintering habitats to the south. The Connecticut River plays a particularly important role in their journeys. "The Connecticut River in general is this major north-south highway," Brown said. "It's New England's longest river. It takes birds from close to their breeding grounds in Canada to places where they winter in the mid-Atlantic and the northeast." Along this natural migration corridor, wetlands, marshes and larger bodies of water offer places for birds to congregate before continuing their journeys. The Hinsdale Setbacks are particularly well suited for these stopovers because of their combination of open water and marshy habitats. Brown explained dams along the Connecticut River have created larger, lake-like areas that provide important habitat for waterfowl. The Hinsdale area includes one of these impounded stretches, along with extensive marshland. "It has different habitat features in close proximity," Brown said, adding that the area's size makes it suitable for large numbers of waterfowl to gather. The concentration of birds can be remarkable. During past spring migrations, Brown said, observers have counted more than 5,000 individual birds at the Hinsdale Setbacks, including large numbers of Canada geese, mallards and American black ducks. Fall migration generally brings smaller concentrations, as birds have more places to spread out before waterways begin freezing. Still, the diversity of birdlife makes the area especially valuable to birdwatchers. According to Brown, the birding database eBird lists 246 species recorded at the Hinsdale Setbacks, making it one of the most species-rich inland birdwatching locations in New Hampshire. "It's truly one of the best inland birding locations in New England, probably," Brown said. A changing migration calendar While waterfowl have traveled through the Connecticut River Valley for generations, the timing of their journeys has become less predictable. Brown, who has helped lead Harris Center birdwatching trips for decades, said shifts in seasonal temperatures have influenced when large concentrations of migrating birds appear. "It used to be a little bit more predictable as far as the time of the calendar year, as when you would see the larger gatherings of waterfowl, both in fall and spring," Brown said. "But climate change is making that a little more unpredictable and generally trending a little bit later in the fall for when we're seeing these concentrations of waterfowl. In the spring, it's trending earlier." The Harris Center has organized spring birdwatching trips for more than 30 years, and Brown said organizers have adjusted the timing of those outings in response to changing migration patterns. Unlike some migratory birds whose movements are strongly influenced by the length of daylight, many waterfowl respond directly to changing environmental conditions. As long as northern wetlands and lakes remain open and suitable for feeding, ducks and geese may delay their southward journeys. "If it's still warm up north in Canada come early November, we might not see a big influx of waterfowl at that point," Brown said. The relationship between water temperature and bird movement is especially apparent at the Hinsdale Setbacks. Brown recalled that when the Vermont Yankee nuclear power plant operated across the Connecticut River in Vernon, Vermont, warm water associated with the facility's cooling operations helped keep portions of the river ice-free for longer periods. That allowed some ducks to remain in the area later into the season. Following the plant's closure, Brown said, the river began freezing more regularly during winter, changing how long waterfowl could remain in the area. These observations illustrate how changes in local conditions can affect the movements and seasonal presence of migrating birds. Exploring the Setbacks The upcoming Harris Center walk will give participants a closer look at these migration patterns while introducing them to some of the region's most recognizable and less familiar waterfowl. Led by Harris Center ecologist Nate Marchessault, the outing will take place from 8 to 11 a.m. on Sunday, Nov. 8, beginning at the Hinsdale Boat Launch on Prospect Street. Participants will travel three miles or less along mostly wide paths, stopping frequently to observe birds and other wildlife. Organizers expect opportunities to see both dabbling ducks, which typically feed near the water's surface, and diving ducks, which submerge themselves to search for food. Depending on migration conditions, participants may also encounter sea ducks or loons. The outing is currently full, although interested residents can join a waitlist through the Harris Center. Brown said field trips like these remain popular because they combine outdoor exploration with opportunities to learn from experienced naturalists and fellow participants. "We've been leading these trips for many decades," Brown said. "Often, staff members and volunteer members of the public can kind of develop a following of people who enjoy coming on these trips for the camaraderie, for the knowledge that they get." He said the programs attract participants with a wide range of experience, creating opportunities for beginners and longtime birdwatchers to share their observations. The Harris Center offers nature programs throughout the year, including birdwatching excursions, guided hikes and slower-paced outings designed for people interested in exploring the outdoors without the demands of strenuous hiking. For those unable to attend the November walk, the Hinsdale Setbacks remain an important location for observing seasonal bird movements independently. Connecting with the natural world Beyond the opportunity to identify different species, Brown believes watching migration offers a deeper understanding of the natural processes taking place around us. Each fall, waterfowl travel hundreds or even thousands of miles between seasonal habitats, depending on the species and their breeding and wintering locations. Their presence along the Connecticut River offers a visible reminder that the Monadnock Region is connected to a much broader network of wetlands, rivers and wildlife habitats. For Brown, taking time to observe these movements can also strengthen people's appreciation for the environment. "Watching the seasonal phenomenon that occurs throughout our natural worlds is important because much of this has been going on since before humans have been here," Brown said. He believes opportunities to observe wildlife encourage people to recognize the importance of protecting the places these animals depend upon. "It's connecting to the more than human world that we often don't prioritize," Brown said. "But when we do, there are considerable health benefits to it. We feel more connected to the world around us."