Byrd took blood samples from loons in Maine, New Hampshire, Montana and Washington state. Part of Byrd’s funding and her long-term dataset, which contains historical banding records and site fidelity information, comes from the Biodiversity Research Institute (BRI), a Gorham, Maine-based nonprofit whose mission is to assess emerging threats to wildlife and ecosystems through collaborative research. Byrd uses the blood samples to look at metabolite measures that indicate how well an individual loon is preparing for its winter migration. BRI is also interested in assessing the effects of mercury on ecosystems.
Because loons are usually near the top of the food chain in their environment, they are a good bioindicator of the accumulation of mercury in a system.
Spending so much time around loons, Byrd has learned something else about the species. Those loon calls we associate with the tranquility of summer on a Maine lake are actually, for the loon, an indication of something a lot less tranquil.
“When they call out in the middle of the night, it’s thought that they’re doing that because it’s quieter or the sound will travel farther, saying, ‘Here’s where I am, this is my territory,’” Byrd says. “If you hear the yodel, that beautiful sound that is so iconic, and if you look around, there might be another loon or an eagle flying overhead. They even respond sometimes to low-flying airplanes. What they’re saying is, ‘I’m ready to take you on if I need to.’”