For the Love of Loons: Increasing Our Conservation AwarenessMar 22, 2023 11:49PM ● By Story and photography by Lisa Ballard
There’s something about the quavering wail of a loon across a lake that touches one’s soul. Loons have returned to Vermont, but 40 years ago, it was rare indeed to hear them yodel. In 1983, only 29 known loons were found on bodies of water in the Green Mountain State. Today, there are about 350 of them, a conservation success story, but not one to take for granted.
“Loons are a great example of a community science program,” says Eric Hanson, conservation biologist with the Vermont Center for Ecostudies (VCE), who has coordinated the Vermont loon program since 1998. “We have over 400 volunteers statewide. They are the eyes and ears across the 200 lakes in Vermont, monitoring these birds, starting with nesting. They record nest failure, hatchings, and chick survivorship. Then we [biologists] ask, why are nests failing? Why are chicks dying? Why are adults dying?”
Loon Life Story
To understand the challenges that loons face, you first need to understand the bird. Formally known as the common loon (Gavia immer) though it has a waterfowl-like appearance, it is more closely related to an albatross than a duck. Vermonters think of it as a freshwater native, but it’s really a saltwater bird that comes inland for a few months each summer to mate, nest, and raise its young. Loons are more noticeable during the summer due to their showy plumage and frequent vocalizations. On the coast, they shed their distinctive black and white feathers, turning plain gray and white. Even their dagger-like bill turns gray, and they keep a lower, quieter profile.
Because a loon’s legs are positioned way back on its long torso, it moves awkwardly on land and typically comes ashore only to nest close to the water’s edge. As a result, loon nests are highly susceptible to changing water levels during their nesting period, mid-May to mid-June. Nests are also vulnerable to predators, such as raccoons, fox, mink, and other egg-eating wildlife, which is a big problem for loons because they don’t reproduce prolifically.
A mother loon typically lays only two eggs. After hatching, the loon chicks quickly take to the water with their mother and then separate from her by early fall, about the time migration back to the ocean begins. But they’re not adults. If they survive, the chicks won’t be mature enough to mate for six to seven years, sometimes longer. Whereas two wild turkeys multiply into 200 wild turkeys in six years, two loons are probably still two loons. The key to their reproductive success is getting to adulthood.
“A big part of nest success is due to the nesting signs that have been put up, telling boaters to stay away,” explains Eric. “Last summer, almost half, 52 of the 106 nest sites around the state, had signs.”
Loons and Lead
What loons eat may have the biggest impact on whether they reach reproductive maturity or not. Loons are masterful fishers, built for the underwater chase. They swim with torpedo-like speed, using their feet for propulsion and maneuvering. Unlike most other birds, their bones are not hollow, and they can quickly exhale the air in their lungs and flatten their feathers, which helps them dive efficiently, but their prowess underwater can also lead to their demise. Some loons become entangled in discarded monofilament (fishing line) and drown, but many more die from lead poisoning that they get from ingesting lead sinkers and jig hooks. Lead sinkers are often mixed into the gravel loons scoop off the bottom of a lake to aid their digestion. They might swallow a lead jig hook attached to fish they eat, and sometimes they’ll mistake a trolling lure for a fish.
“In 2007, the state of Vermont banned lead sinkers under a half ounce, but we still see loons dying from this,” says Eric. “For 15 years it made a difference, but there’s been an uptick in loon mortality in the last five years. We don’t know why exactly. It might be because there are more loons.”
Starting this summer, the VCE is implementing a lead fishing gear reduction project, which includes collection spots around lakes and a PR campaign asking anglers to look inside their grandfather’s tackle box. “We’ll try to reach out to anglers through the lake associations, the media, and advertising,” says Eric. “Twenty to 30 birds aren’t dying annually any more, but one or two are. With only 350 loons in the state, it makes a difference.”
Beyond lead fishing tackle and discarded monofilament, loons face two other threats—diseases and climate change. In 2014, a loon loaded with malaria was discovered at the New Hampshire Veterinary Diagnostic Lab. Since then, there have only been a half dozen or so confirmed mortalities from malaria in the region, but researchers in Vermont are starting to look for it, wondering if malaria is moving farther north.
Loons can also die from aspergillosis, a fungal infection. “Stressed birds get it, which is why exhausted, injured, or malnourished loons don’t do well in rehabilitation facilities,” explains Eric. “It used to be more of a winter thing on the ocean, but it’s now on lakes.”
Climate change impacts loons too. More of them are sticking around longer in the fall and sometimes into the winter. On big lakes like Lake Champlain, freeze-up is happening much later, in January or February, which is when loons molt, and then they can’t fly.
On the bright side, most of the big lakes in Vermont have loon activity now, though not all for nesting. Within the last five years, loons have begun appearing in west-central Vermont, including Lake St. Catherine near Poultney and Lake Bomoseen near Castleton. Eric credits the lake associations and numerous volunteers around the state for much of this good news. “People like loons and talk to other people about them,” says Eric. “We’ve got a huge crew of people watching. Vermont is one of the most loon-aware states around.”
On a loon report card, Eric grades loons an A-. “My biggest concern is the one to two birds per year that die from lead, but on the whole, they’re doing well. They’ve expanded statewide. They might not nest on Lake Willoughby, but singles will hang out there. They’ve learned to survive on busy lakes, like Lake Dunmore, on just a quarter-mile stretch of island or lakeshore. They don’t need wilderness, but they do need cover, meaning marshes and riparian areas. People are aware to not allow sediments and phosphorous into their lake, but they’ll mow to the water’s edge, which means loons won’t nest there.”
It’s hard to imagine Vermont without loons. There’s something evocative and mournful about their cry. Perhaps they’re really calling to us to care about them. “Loons are a way to increase awareness of lake health,” concludes Eric. “It’s not just about the loons, though the loons are the rock stars!”
Vermont Center for Ecostudies