Bluebirds are primarily insect eaters but do eat a lot of fruit in colder months. Some dedicated bird lovers have taken to feeding birds live insects, especially during the nesting season. Several species will eat mealworms when offered but the primary bird that people are hoping to attract is the Eastern Bluebird. Since mealworms are dry and have legs, they can easily crawl out of feeders that are made of wood or other rough material. Glass, metal or a hard plastic feeder work the best.