To hear a Common Loon in the wild during summer, you’ll need to find a northern, freshwater lake where a pair is nesting. But to find that same Common Loon in winter, you’ll likely need to look on a saltwater bay. This shift from fresh to salt water would kill most animals. But loons — along with many ducks and other water birds — have evolved to make that move. It’s possible that breeding adults nest on fresh water in order to save their energy for raising chicks.More info and transcript at BirdNote.org. Want more BirdNote? Subscribe to our weekly newsletter. Sign up for BirdNote+ to get ad-free listening and other perks. BirdNote is a nonprofit. Your tax-deductible gift makes these shows possible.