You may notice Eagles shiver causing them to fluff up. This movement and poofing is actually to trap and create air pockets within their thick plumage which helps them insulate during those extra cold times. Eagles don’t just come together following a food source, they will actually huddle up next to one another for warmth too. Sharing body heat, usually in a more sheltered perch for the night. But the most beneficial and effective way these incredible survivalists withstand frigid temperatures is movement. Constant flying, hunting, feeding, just like with us, keeps the blood circulating and creates warmth from within.