Bird of the Month by Russ Chappell
Agile aviators, tree swallows prey on flying insects near fields and wetlands, their blue-green feathers flashing in the sun.
When not flying they perch on utility wires and shrubs, scouting for prey. A vocal species, you can often locate them by their cheerful chirping calls while pursuing insects.
They are streamlined songbirds with pointed wings, short, squared or slightly notched tails and black bills, nearly six inches long with wingspans reaching over 13 inches. Males have blue-green backs and white fronts, dark flight feathers and thin black eyemasks, females are duller, with brown upper parts, and juveniles are completely brown above.
They supplement a primary diet of insects with berries from fruit-bearing shrubs, and prior to breeding may visit backyard compost piles looking for eggshell to add calcium to their diet.
Named for their custom of nesting in tree cavities, they are also attracted to nest boxes, allowing scientists to make them one of the best studied species in North America. Note: if you install a nesting box, attach a guard to restrict access to the eggs and young. Nest predators include snakes, raccoons, bears, chipmunks, mink, weasels, mice and cats. During migration and non-breeding periods they live in the open, without nests or nesting boxes.
The female may complete her nest in a few days or as long as two weeks. It routinely consists of grass, pine needles, mosses, rootlets, aquatic plants, animal hair and materials like cellophane or cigarette filters, and is lined with feathers from other bird species, usually provided by the male. Parents share nesting duties evenly.
A clutch consists of four to seven pale-pink eggs that fade to white in three or four days. Incubation takes up to 20 days, with chicks hatching helpless, eyes closed, their pink skin covered with down, and able to leave the nest in 15-25 days.
Not on the 2014 State of the Birds Watch List, and rated eight out of 20 on the Continental Concern Score, tree swallows are not considered endangered.
The Prescott Audubon Society is an official chapter of the National Audubon Society. Check it out online at PrescottAudubon.org.
Bird of the Month by Russ Chappell
This colorful green-and-gray species is an infrequent migrator and may visit your backyard year round.
Males display an iridescent patch on the throat called a gorget extending over the head, while females have a small red patch. Both genders have short legs, slender bills and broad tails.
Anna’s hummingbirds dine on nectar from a variety of flowering plants, tree sap leaking from holes created by sapsuckers, and a variety of small insects, often captured in flight. If you don't see them at a feeder or flowers, check out nearby trees and bushes, where they often perch and announce their presence with song.
During courting a male attracts the attention of a potential mate by climbing high into the sky and diving straight down at full speed, stopping abruptly a few feet in front of her, announcing his arrival with a distinctive sound created with his broad tail. Males and females are not exclusive, and either sex may mate with more than one individual per season, while the females build nests and care for the young.
Nests are constructed with an assortment of plant parts, feathers, down, and spider webs as mom sits inside the inch-high by one-half inch diameter, cup-shaped bowl, forming it around her. There are up to three broods per year, each with two half-inch by one-third-inch white eggs. Incubation lasts 16 days, and nesting time 20 days. The chicks hatch with minimal down and are virtually helpless.
They maintain a body temperature as high as 107 degrees Fahrenheit, but will enter torpor to slow down breathing and heart rate when the weather cools, then magically return to full activity once the weather improves.
Anna’s hummingbirds are a welcome addition to any birder’s list, and bring an upbeat atmosphere to any backyard. To attract them, simply fill your feeder with one part sugar to three parts water, without honey or coloring, and stand by to be entertained with energetic and exciting flight demonstrations!