Here’s what Maine Audubon learned from decades of loon counts

The No. 1 killer of Maine’s most iconic summer bird is boat strikes for the first time ever, pushing lead fishing tackle down to No. 2. Waves from the wakes of boats, which are more numerous than ever on lakes and ponds, can flood out nests, and development and the effects of climate change continue to pose challenges.

But in spite of the human-made dangers they navigate, the state’s common loon population has nearly doubled in the last 40 years in southern Maine, said Hannah Young, the Maine Audubon Society’s loon count coordinator.

The loon’s success is credited to restoration projects, better monitoring of stresses on the population and changes in laws related to lead fishing tackle and boating, Young said.

Maine Audubon holds the count for a half hour each year with more than 1,500 volunteers tallying loons at the same time on hundreds of lakes and ponds, mostly in southern Maine. This year’s 41st annual loon count will be held from 7 to 7:30 a.m. Saturday, July 20.

Maine’s loons are iconic to residents’ and visitors’ summer experiences, their distinctive wails piercing the stillness of the state’s lakes and ponds. Maine Audubon, along with state biologists, has been monitoring and studying loons for decades, tracking populations and health trends, and giving the birds a little help when they need it, such as providing artificial nesting sites. Maine has the largest population of loons in the eastern United States.

Although the loons have overall healthy totals, last year showed a decrease from the year before in the number of adults.

“If that happens again this year, it will be the third in a row, but there was an increase in chicks last year,” Young said. “We’re not worried yet because everyone is still producing.”

The southern Maine population was estimated at 2,892 adults and 411 chicks after last year’s count. Volunteers tallied loons on 374 lakes and ponds, of which 69 were north of the 45th parallel (roughly the midline of the state), Young said. Northern volunteers counted 522 adults and 31 chicks, under the direction of the Biodiversity Research Institute, based in Portland.

There isn’t as much count data from the northern parts of the state because there are fewer volunteers, although organizers are working to increase the number.

One of the biggest threats to nesting loons is boat wakes, the waves from which can flood out a loon nest perching on the shoreline of a lake or pond, Young said. There are more boats on the lakes and ponds now, increasing that threat.

Maine’s new law requires boats involved in wake surfing to be in at least 15 feet of water and 300 feet or more away from shore to protect the loons. All boats must travel at no-wake speeds within 200 feet of shore.

Loons also are susceptible to land predators and they lose nesting sites to development and to water level fluctuations from climate change. There is also still a lead poisoning problem from fishing tackle.

Although loons can get avian flu, none has been found in Maine birds to date. New Hampshire reported a loon that died of avian malaria, which also has not been seen in Maine birds.

Maine Audubon helps loons nest successfully by monitoring adult pairs. If no chicks have been produced for 3-5 years or if they keep getting killed, the Audubon, through its loon restoration program, provides an artificial nesting site called a raft.

More than 100 of them are scattered around the state’s lakes and ponds. The Audubon has to be careful to not overpopulate a body of water and make the loons compete for food.

“It literally is a raft made of cedar logs and other materials,” she said. “But it takes commitment to build, monitor and put them out.”

There are injured loons and abandoned eggs every year, but the overall population is healthy, she said.

Loons aren’t necessarily lone pairs on a lake or pond. Big groups of about 40 loons have been reported on Sebago Lake.

“They visit other lakes. That’s why loon count is a certain period of time. We tell volunteers not to count loons flying over the lake for that reason,” Young said.

She said the statewide loon count couldn’t happen without its volunteers, and in some areas, it has become a community-building event with meals and other activities.