Initially, Byrd was interested in loons because of their unusually aggressive behavior. Loons will kill each other in fierce territorial clashes, which brings up a key question: Why defend one’s territory to the death when moving to another lake would seem simpler? That leads into Byrd’s research on why loons settle where they do, and how vulnerable the birds are to changes in their habitats and the climate.
“In Connecticut, for example, there are suitable lakes and habitat, but there are no loons,” she says. “There is something that’s limiting the edge of their range, whether it’s water clarity, lake surface temperatures, fish assemblages or dissolved oxygen levels. The question is: Are those the same things that are predicted to be affected by climate change?”
The research combines demographic analysis, physiological measures and behavioral observations of loons across a range of climatic conditions to predict how changes to lake characteristics could impact loon distributions.
To that end, Byrd spent the past two summers banding loons on lakes in the areas of Rangeley and Greenville in western Maine. She also traveled to Montana and Washington state, and recruited biologists in other regions with loon populations to gather behavioral observations of territorial loons.
Byrd will combine her more than 2,000 recorded observations with analyses of lakes — both with and without loons — to build a model that shows why loons locate where they do. That model will indicate what will happen to loons if there are climate change-related shifts to lake characteristics.