Tree swallow
Tree Swallows, the earliest among swallow species to return to their nesting grounds, are the leading edge of early migrants this week arriving in New York, Minnesota and Washington state from their wintering grounds in Mexico, Central America and the Caribbean. They'll soon nest in tree cavities and human-made nesting boxes. These aerial acrobats are fun to watch as they swoop, twist and turn to dine on insects in flight.

JanetandPhil (CC BY-NC-ND 2.0)