Early Birds of Spring

A sure sign of spring in Forest Park is the return of Tree Swallows Tachycineta bicolor. These are one of 4 species of swallows that frequent the park, and are historically the first to return from overwintering grounds in Mexico, Central America, and the Caribbean.

The Tree Swallow is very commonly found close to larger bodies of water such as Post Dispatch Lake and Deer Lake in the park. With a blue-green iridescent back and snow white belly it is hard to mistake this species for any other swallow. They chatter as the fly low over open water eating small insects on the wing, usually flying in large circles and gliding.

Tree Swallows are cavity nesters, and in a natural setting, use hollowed out holes in dead trees. But with increased competition for these limited numbers of naturally occurring cavities they have adapted to nesting in man-made structures. They readily nest in boxes that are designed for Bluebirds and can be found specifically using them on Picnic Island in the park. Forest Park Forever has established 16 Bluebird boxes throughout the park and these can be used by as many as 4 different types of species.

A very distinct way of knowing if you have nesting Tree Swallows is that they line their grass and twig nests with large feathers from other bird species. They sometimes can be seen fighting for these feathers mid-air. Normally they raise one set (brood) of young each year with an average of 4-7 eggs laid. They can defend their nest quite vigorously when young or eggs are present.

So next time you are out walking on Picnic Island or around Post Dispatch Lake keep a lookout for these phenomenal fliers that call Forest Park home for the summer.