Tree Swifts: Hemiprocnidae

Physical characteristics: Crested tree swifts range in length from 8.2 to 9 inches (21 to 22.6 centimeters) and weigh 0.7 to 1.0 ounces (20 to 26 grams). They have long, narrow wings and forked tails. All birds have blue-gray plumage, green-blue crests on their foreheads, and coloring that looks like black eye patches.

Male crested tree swifts have a pale rufous, brownish red, patch below the eye. That coloring extends to ear coverts, small feathers near the ears. On male bodies, feathers are white below the breasts. Wings are mainly blackish brown. Some wing feathers are pale gray and blue. Tails are blue-gray on top and pale gray on the back side.

Female crested tree swifts have black plumage in the area between their eyes and bills. That black coloring extends to their ear coverts. Below the black plumage is a thin line of white plumage that looks Crested tree swifts live in forests and gardens in Southeast Asia. (Illustration by Bruce Worden. Reproduced by permission.) like a moustache. The line extends from the face to the sides of the head below the ears. Female crested tree swifts have dark gray throats.

Crested tree swifts were once thought to belong to the same species as the gray-rumped tree swift. However, the crested swifts do not have pale gray plumage on their rumps.

Geographic range: Crested tree swifts live in India, Nepal, Sri Lanka, Bangladesh, Myanmar, Thailand, China, Cambodia, and Vietnam.

Habitat: Crested tree swifts live in deciduous forests, in open areas near trees, and in home gardens. Most birds live in areas with altitudes, heights, of no more than 1,197 feet (365 meters). However, birds also range at higher altitudes of 3,937 to 4,593 feet (1,200 to 1,400 meters).

Diet: Crested tree swifts eat flying insects like the small, two-winged midge.

Behavior and reproduction: While crested tree swifts are sedentary, don't migrate, the birds in India sometimes fly to different parts of the country when seasons change. Crested tree swifts are nocturnal and are active in the later part of the night. Birds look for food in pairs or in small groups of six to twelve birds. They fly in circles to feed, and their call is described as harsh.

Crested tree swifts often perch upright on branches with no leaves. They have favorite perches and stand with the tips of their wings crossed.

The breeding season varies by location, but birds usually mate between December and July. The male and female birds build a tiny nest out of pieces of bark, feathers, and saliva. Birds attach the nest to a branch with saliva, and the female lays one gray egg. Both parents incubate the egg. They do this by perching upright and covering the egg with their feathers.

The egg hatches after about three weeks. Both parents care for the chick. The young bird fledges approximately fifty days after the egg was laid.

Crested tree swifts and people: Since the crested tree swift population is large and found in many countries, they are often studied to learn more about the family.

Conservation status: Crested tree swifts are not at risk of extinction. ∎