The Eastern Kingbird is one of the first species I learned to identify when I first began birding in Maryland. One thing I love about kingbirds is their tendency to attack perceived rivals in their territory (at least while they are in the U.S.). I've seen them pursue birds many times their size, harassing them until they leave. On Merritt Island, I once saw one harass a Turkey Vulture for quite some time. Their aggressive behavior towards other birds is partly what earns Eastern Kingbirds their scientific name Tyrannus tyrannus. They also sometimes raise their crown feathers, and on occasion, you may see yellow or red feathers in their crown.