Black-capped chickadees are omnivorous and have a varied diet that changes with the season. In summer, their diet primarily consists of insects, especially caterpillars, spiders, and larvae. In winter, the diet includes about half seeds, berries, and other plant matter and half animal food (insects, spiders, suet, and sometimes fat and bits of meat from frozen carcasses). At bird feeders, they take sunflower seeds, peanuts, suet, peanut butter, and mealworms.