Monday, July 23, 2012

Eastern Kingbirds




Eastern Kingbirds -- © Dave Spier

Eastern Kingbirds are easy to recognize; they are charcoal above, black around the eyes and crown, and white underneath including a white throat. The clincher is a black tail with a white tip. They are smaller than robins and often fly across a field with wings fluttering. If you are familiar with its relative, the phoebe, another type of flycatcher, the kingbird is larger. The Great Crested Flycatcher is about the same size as the kingbird.

Eastern Kingbirds (Tyrannus tyrannus) show a slight preference for nesting near open wetlands, but can be found in many rural settings with open areas and nearby trees. Given a choice, they favor the edges of ponds, streams and marshes. If there’s an island with trees, this is prime real estate because the water affords protection from four-legged predators. There are no islands at Lock Berlin Park (beside the old Erie Canal in Wayne County, NY), but I found a pair of kingbirds nesting high in a dead tree between the old canal and a small wetland east of the picnic area. The nest was in a fork of the trunk and partly hidden by Virginia Creeper vines.

Lousy photo of a kingbird nest...

Their scientific name, Tyrannus, is the same as tyrant and refers to their aggressive behavior, even toward birds as large as hawks and crows which are potential nest predators. The name "Kingbird" refers to a seldom-seem patch of golden or orangish feathers on the crown. The color resembles flowers and may be used to attract insects which the kingbird eats. The birds are members of the flycatcher family and often hunt from an exposed branch or wire. When an insect buzzes by, the kingbird flies out, grabs it in its beak and returns to the perch or takes it to the nest.

There’s a kingbird in the fields around the Montezuma Audubon Center (Savannah, NY) and it sometimes sits on top of the Purple Martin house to watch for insects. The martins tolerate its presence, but it would do little good to try and chase it. In fact, kingbirds are essentially bullies and have been known to attack other insect-eating birds and steal their prey.

Kingbirds are known to eat over a hundred species of insects. Unfortunately, dragonflies are on their menu. The dragonfly’s nickname, "mosquito hawk," will tell you why we’d prefer them to be left alone. About a third of the kingbird’s diet is from the order Hymenoptera (bees, wasps, flying ants, etc.). The kingbird’s nickname of "bee martin" refers to its habit of hanging around beehives and eating honey bees as fast as they can. Before songbirds became protected, there was a bounty on kingbirds. It turns out that kingbirds eat primarily drones, the stingerless males, with little consequence to the colony. Drones are identified by being darker and larger than worker bees (which can sting).

Eastern Kingbird at Montezuma National Wildlife Refuge, Seneca Falls, NY.

A quarter of the kingbird’s intake is beetles, including types we consider harmful. Grasshoppers and crickets average 12% of the summer diet. Yes, flycatchers eat flies, but those only amount to 10% or less – little more than appetizers. If there’s a shortage of insects, then frogs, snails and small fish might become prey. Perhaps as a last resort, small fruits and seeds (like wild grapes and pokeberries) are eaten.

The Eastern Kingbird's summer range covers the eastern half of the United States and extends northwest across the upper Plains and Rockies well into Canada.  They are mostly absent from the Southwest. The eBird range map shows a concentration down through the Great Plains.  Migration takes them down through eastern Mexico and Central America to their winter range across a large portion of South America, including the western Amazon, and as far south as the Argentine Pampas. During our winter (South America's summer), kingbirds are much more dependent on eating fruit.

Corrections, and questions always welcome at northeastnaturalist@yahoo.com or connect with me on Facebook and my photo page.

1 comment:

Edward Cordes said...

Thsnks for the great info. I wish we had more around here. They can eat all the beetles they want around our flowers.

Ed