After a four-mile hike through overgrown thimbleberry bushes, Jessica Mejia and Tina Zenzala arrived at Lake Mokowanis in Glacier National Park’s Belly River. The two walked to the water’s edge and quickly spotted a pair of loons swimming in the middle of the lake. The mottled black and white plumage and iridescent black head of the birds make them easy to spot.
Upon closer inspection, the loons’ red eyes are evident – indicative of the breeding season. In a few months, the birds will return to their gray and white color pattern and the vibrant crimson of their eyes will fade to a dull reddish brown.
Zenzala dropped her backpack and watched the pair through her binoculars as Mejia marked the sighting in the citizen science app on her phone. “It doesn’t look like these two have any chicks,” Zenzala noted.
Zenzala and Mejia are part of the Common Loon Citizen Science Project in Glacier National Park, which began in 2005 to provide park biologists with a better understanding of Glacier’s loon population. Their trip was during breeding season and they hoped to find a pair of loons with chicks at one of their survey sites. Loons have slow reproductive rates and a pair will only have two eggs per season. Only six loon chicks are born at Glacier each year – of these, half will survive.
In addition to slow reproductive rates, loons need protected habitat to survive and produce offspring. With expanded access to remote lakes, humans are causing more disturbance to loons, which must nest along the shoreline due to their inability to walk far on land. Loons evolved over a million years ago, which makes them well adapted to a specific environment, but unfortunately, this makes it difficult for them to adapt to environmental changes. Data collected by citizen scientists helps park managers better understand threats to loon population health and how best to respond to them.
“I can’t gather all this data alone,” said Kelsey Cronin, who leads the project. “Citizen scientists make it all possible.” Zenzala is in her fifth year as a citizen scientist and doesn’t plan on quitting anytime soon. “We have stars who have been with us for over 15 years,” Cronin said.
The citizen science project not only helps park biologists better understand loon reproduction and population numbers, but also creates advocates for the bird. “Citizen science makes it much more accessible,” Cronin said. “With more attendees, there’s increased public awareness and more people who care about what’s going on with these birds.”
Zenzala and Mejia’s trip to the belly was part of a larger statewide project called “Loon Days,” in which every lake in Montana known as a loon breeding ground is surveyed. The project is a collective effort of the National Park Service, Fish Wildlife and Parks, Forest Service, Department of Natural Resources and Conservation, Confederated Salish and Kootenai Tribes, and Blackfeet Nation. Each department has its own citizen scientists who venture into the backcountry in search of loons, with high hopes of finding a pair with chicks.
The next morning, back at base camp, Zenzala and Mejia pitched their tents near the waterline of Lake Cosley. As the sun slowly crept over the jagged peaks and clouds settled inches above the still water, a haunting cry broke through the silence: the whine of a loon seeking its mate. Mejia and Zenzala stopped to listen before venturing into the water – they had seen a couple of loons on the lake the day before, but now the loon’s cries went unanswered.