Around 200 pairs of Bald Eagles call Colorado home, with most breeding pairs remaining in the state year-round, rearing their young here in the spring and summer. Why, then, does Colorado’s Bald Eagle population surge to well over 1000 birds in the late fall and winter? Migration is the obvious answer, but as you might suspect, it’s a bit more complicated than that. Why do some eagles migrate while others do not? Here we’ll explore the answer to that question and more.