Swifts and Hummingbirds: Apodiformes
SWIFTS AND HUMMINGBIRDS: Apodiformes
The name Apodiformes is based on the Greek words "a pous," meaning "without foot." Apodiforms have small feet and their legs are short. Many birds in this order cannot walk, and they are unable to escape quickly by simply walking and then flying away if they land on the ground.
Although their feet are weak, apodiforms are strong fliers because they have thick shoulder bones and long, powerful breastbones. Because of their neck muscles, these birds can move their heads quickly.
Some physical differences and behavioral differences separate the three families in the Apodiformes order. A family is a group of birds that have similar characteristics.
Birds in the swift family (Apodidae) eat, mate, and sleep in the air. These birds, also called typical swifts, have long, pointed wings. Their head-to-tail length ranges from 3.4 to 9.6 inches (9 to 25 centimeters). They can weigh from 0.2 to 7.6 ounces (5 to 205 grams). The swift has a short bill and a large gape, which is the width of the mouth when it is open. The swift opens its mouth to catch prey, or insects hunted for food.
Swifts' feathers are brown or black, with white patterns in some birds. Male and female birds have similar plumage (feather color).
Tree swifts belong to the Hemiprocnidae family. Unlike swifts, these birds can perch in trees. Birds range in length from 5.8 to 11.5 inches (15 to 30 centimeters), and weigh from 0.8 to 2.9 ounces (21 to 79 grams). Tree swifts have small, flat bills, large gapes, and whiskers. They have long wings and forked tails.
Tree swifts are also called crested swifts because of the crest (clump of feathers) on their foreheads. Plumage is brown or light gray, other colors may include blue, green, and white. The plumage color of the male and female birds differs.
Hummingbirds belong to the Trochilidae family. They are named for the humming sound made by their quickly vibrating wings. Hummingbirds can fly backwards and hover, staying in one place by flapping their wings.
Hummingbirds range in length from 2 to 8.7 inches (5 to 22 centimeters), and weigh from 0.07 to 0.7 ounces (1.9 to 21 grams). These birds have long, thin bills and long, forked tongues.
The hummingbird family is the most colorful member of the Apodiforme family. Plumage colors include red, green, pink, blue, yellow, and purple. Usually, female birds are less colorful than males, which helps the females hide their young from predators, animals that hunt prey for food.
Swifts are found throughout most of the world. They live on every continent except Antarctica and do not live in polar regions.
Swifts and hummingbirds live in coniferous forests that do not undergo seasonal changes. They also live in deciduous forests where trees lose their leaves during cold or dry weather. Hummingbirds live in deserts, and members of both families inhabit grassland areas where there are few trees. Hummingbirds also live in wetlands, areas where the land is low and wet.
Tree swifts live in rainforests, areas where heavy rain produces abundant growth.
Members of all three families live in trees. Swifts sometimes make nests in chimneys and on cliffs. Some hummingbirds and swiftlets live in caves. In addition, some swifts and hummingbirds migrate, traveling to another area where food is more plentiful. The chimney swift lives in North America and spends its winters in Central and South America.
Swifts and tree swifts are insectivores, birds that eat insects. Swifts catch most prey while flying with their mouths open. The type of insects eaten depends on where the swifts are and the weather. On warm days, there are more insects in the air. Swifts' prey includes mayflies, termites, and ants, and sometimes even spiders.
Tree swifts perch in trees and watch for prey, such as flies, bugs, and ants. They fly after prey and after catching it, they swallow it whole.
Hummingbirds use their long tongues to drink nectar, a sweet liquid found in flowers. Since hummingbirds live in many countries around the world, members of this family drink nectar from thousands of different flowers. Hummingbirds are likely to feed on flowers that are red, orange, and yellow. The birds may also eat insects.
BEHAVIOR AND REPRODUCTION
Swifts are sociable and live in large groups of birds called colonies. Tree swifts are usually found alone or in pairs. They may, however, form a group of ten to twelve individuals. Both birds, swifts and tree swifts, are noisy birds and may create quite a bit of noise when congregating.
Hummingbirds are solitary, pairing up only to breed. Male hummingbirds are territorial and chase other birds away from the area where they feed. When food is scare, swifts and hummingbirds may hibernate.
Swifts and hummingbirds are active during the day. Tree swifts are crepuscular (kri-PUS-kyuh-lur), meaning that they become active at twilight or just before sunrise.
Apodiformes use various materials for their nests. The birds "glue" their nests together with saliva, a watery solution in their mouths, thereby hardening and holding the nest. Swifts make nests out of twigs, feathers, and other materials that they catch as it floats through the air. Tree swifts use feathers and bark from trees for their nests. Hummingbirds weave spider webs into their nests.
Collocalia swiftlets in Asia use only saliva to make their nests. People eat these nests in bird's nest soup.
Swifts and tree swifts are monogamous (muh-NAH-guh-mus), meaning that they mate with only one partner. Hummingbirds are polygamous (puh-LIH-guh-mus) and do not mate with the same partner, but instead have a number of different partners. After mating, the male hummingbird leaves and the female lays two eggs.
The tree swift lays one egg, while the swift lays a clutch of one to six eggs. Males from both families help care for the young.
Swifts spend so much time in the air that they are usually safe from mammal predators. The birds fly rapidly, but sometimes are caught by hawks. In addition, brown tree snakes eat swifts on some islands.
SWIFTS, HUMMINGBIRDS, AND PEOPLE
For thousands of years, people in Asia have used cave swiftlet nests as the main ingredient for bird's nest soup. There is no known significant relationship between people and tree swifts.
People place hummingbird feeders in their yards because they enjoy watching them fly about and drink flower nectar. The birds pollinate the flowers when they drink the nectar, by transferring flower pollen (male sex cells) from the stamen to the pistil, the organ that bears the seeds. This eventually leads to the production of more flowers.
FLIGHT PATTERNS OF MIGRATING BIRDS
Migratory swifts and hummingbirds fly great distances, often without stopping until they reach winter homes where there is more food. In the wild, swifts may travel at a speed of more than 100 miles (160 kilometers) per hour. The smaller hummingbirds timed in laboratories flew at speeds ranging from 30 to 53 miles (48 to 85 kilometers) per hour.
Swifts alternate between wing movement and gliding, allowing the wind to assist in moving them along. Hummingbirds can stop in mid-air by flapping their wings up and down, allowing them to hover and feed.
Some species of swifts and hummingbirds face threats to their survival, according to the World Conservation Union (IUCN). Nine hummingbird species are Critically Endangered, facing an extremely high risk of extinction, as their habitat is lost due to development, farming, and logging. Six hummingbird and swift species are Endangered, facing a very high risk of extinction. Brown tree snakes accidentally brought to Guam by ships ate many of these birds on the island. Other swiftlets died when pesticides were sprayed to kill insects.
FOR MORE INFORMATION
Attenborough, David. The Life of Birds. Princeton, NJ: Princeton University Press, 1998.
Baicich, Paul J., and Colin J. O. Harrison. A Guide to the Nests, Eggs and Nestlings of North American Birds. San Diego, CA: Academic Press, 1997.
Sibley, David, Allen. The Sibley Guide to Birds. New York: Alfred A. Knopf, 2000.
Wells, Diana. 100 Birds and How They Got Their Names. Chapel Hill, NC: Algonquin Books, 2002.