Northern cardinals get their red color from carotenoids, which are pigments found in many foods, including red and purple fruits, carrots, ripe tomatoes, and autumn leaves. When cardinals eat these foods, their bodies convert the yellow carotenoids into red. The quality of a cardinal’s red color can indicate how well it’s eating, and brighter plumage can be a sign of overall fitness.

Northern Cardinal with Flattened Crest