Kingfishers are very interesting birds. Illinois is the native home to one special variety: the belted kingfisher. In the summer, these especially easy to spot!
The belted kingfisher is a medium sized, blue and white bird. The female looks slightly different than the male pictured above, with orange patches on her white stomach. Belted kingfishers can be seen along rivers and lakes in Illinois, although their range is big enough that they have also been seen near the ocean, outside of Illinois.
Kingfishers are coraciiformes — they have large, plier-like beaks, and they make burrows when they nest. There are many kingfisher species other than Illinois' belted kingfisher, and all of them are known for having similar traits: a small body, and a very large beak compared to their body size. This large beak lets kingfishers catch larger fish than they would otherwise, and is sort of like a set of needle-nosed pliers. Birds as a whole have evolved many different kinds of beaks as they have diverged into different species, and the kingfisher's beak is certainly one of the more specialized examples.
Kingfishers also have incredibly good vision, superior to many birds (other than birds of prey). Their vision is this good so they can see underwater prey from a far distance. They also have fairly good color vision, which is rare for birds. They can judge underwater depth with their exceptional eyes, which is important for their hunting style. When they swoop down, they're able to judge whether the water is deep enough to hunt without injury. Kingfishers' depth perception also helps them see how deep their prey is in the water.
Instead of making a nest in a tree, like most birds we see in Illinois, the belted kingfisher digs a burrow with its mate alongside a water source, and lays its eggs there rather than up in a tree or on a post. The next time you're out on the river or lake in Illinois, keep an eye out for the flash of a belted kingfisher's blue beauty!