Long-Tailed Titmice: Aegithalidae

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LONG-TAILED TITMICE: Aegithalidae

BUSHTIT (Psaltriparus minimus): SPECIES ACCOUNT

PHYSICAL CHARACTERISTICS

Long-tailed titmice range in length from 3.5 to 6.3 inches (8.9 to 16 centimeters) and weigh 0.14 to 0.32 ounces (4 to 9 grams). The birds derive their name from their characteristic long tails, with the longest tail belonging to the long-tailed tit, whose tail makes up half of its length. Both male and female adults tend to be alike in their feathers, with dark gray or brown, and sometimes lighter shades, on top, and with white underneath. Some species have what looks like a black mask. Some have pink tints to their feathers on their tails and shoulders. Their feathers are arranged loosely all over their bodies, giving them a fluffy look. Given their size and appearance, they are often a favorite with birdwatchers.


GEOGRAPHIC RANGE

One species of titmice, the bushtits, can be found in western North America, from the northernmost parts of British Columbia to the southern regions of Mexico. Five species are found in the Himalayas, and mountainous regions of western China. Long-tailed tits, the species that is most common, have a range from Western Europe and Asia, to China and Japan. Pygmy tits, the smallest titmice species, can only be found on the Indonesian island of Java.


HABITAT

Long-tailed titmice can be found primarily inhabiting the shrub layers and edges of forests and woodlands among the leafy trees and dense thickets. Those inhabiting the Himalayas and mountains in China are normally found at elevations between 4,000 and 8,860 feet (1,200 to 2,700 meters). White-throated tits can be found living in the mountains at elevations as high as 13,100 feet (4,000 meters), up to the top of the tree line, the elevation where trees do not grow. North American bushtits are also at home in suburbs, parks, and gardens.


DIET

Long-tailed titmice are primarily insectivores, eating insects, their larvae, the newly hatched wingless form of insects, and eggs, spiders, and other invertebrates, animals without backbones, and sometime eating fruit, primarily berries, and seeds. They show remarkable skill in the use of their bodies and limbs. These titmice are at ease even when hanging from the thinnest branches, as they hold their food with one claw and nibble at it with their stubby bill.


BEHAVIOR AND REPRODUCTION

Most of the species of long-tailed titmice live most of the time in flocks of their own species. These small flocks usually number between five and ten birds. Occasionally, they might also be found in flocks of composed of related birds. The birds of this family tend to be sociable. Their chatter is usually heard before they are visible to observers. Some groups can be observed flying in a line of single birds from between the bushes. At night the birds roost, sleep, together, lining up on a branch, and huddling in order to preserve body heat. In that case, the birds that are the largest of the flock are most likely found in the middle of the line, the point at which most of the heat is held. Long-tailed tits can sometimes be found roosting in ground holes.

Long-tailed titmice have a breeding season from January to July. The pygmy tit of Java breeds from August to November. During the breeding season, the flocks break down into individual pairs, though if it is cold, the largest group still might roost together. If the nest has been built already, the individual pair roosts alone in their nest.

Long-tailed titmice build nests that are an enclosed oval shape, or possibly a more elongated structure. They are made from moss, lichen, spider silk, and plant material. The light color of the nests are most likely an attempt to protect the nest by making them the same color as the light background breaks in the tree canopy, upper layer of the forest. A hole is put at the top of the nest to serve as an entrance. Nests have been constructed with a soft lining that might include more than 2,000 feathers. These nests are usually found low in the woodland shrub layer, held up off the ground by branches. Clutch size, the number of eggs laid at the same time, is between two and twelve eggs. The clutch is incubated for a period of twelve to eighteen days. Both males and females, and sometimes other members of the flock will feed the young. Fledging, growing feathers needed for flight, occurs within three weeks of hatching. Chicks remain with the parents' flock for the first winter. The birds raise two broods, a group of birds raised at the same time, a year. The bird has a life span of up to eight years.


LONG-TAILED TITMICE AND PEOPLE

Bushtits are common visitors to garden feeders. Other long-tailed titmice do not visit feeders, but are often observed in garden trees and in parks and remain popular with birdwatchers.


CONSERVATION STATUS

Long-tailed titmice can be found in large numbers throughout their habitat range, and are not classified as a threatened bird family. However, up to 80 percent of the population can die during a hard winter. The species native to the Himalayas and Chinese mountains are also common locally, except for two species, the sooty tit and the white-throated tit. They are both listed as Near Threatened, close to becoming threatened with extinction. The pygmy tits of Java are also very common, however, the continual danger of deforestation, cutting down of forest, might be a concern for their survival in the future. As a species that relies on the dense forests for their habitat, the loss of such forests would definitely pose a threat.

BUSHTIT (Psaltriparus minimus): SPECIES ACCOUNT

Physical characteristics: Bushtits range in length from 4 to 4.5 inches (10 to 11.4 centimeters), with an average weight of 0.18 to 0.21 ounces (5 to 6 grams). They are tiny birds, and like other long-tailed titmice have loose feathers that can result in a fluffy appearance, especially when spreading their plumage. The bushtits that inhabit the interiors of their range are usually gray on top with paler gray undersides; the coastal birds have brown caps. Southwestern members of this species have black masks that go all the way to their ears. This variety was once considered a separate species, the black-eared bushtit, but is no longer categorized separately. Female bushtits are known for their cream to yellowish eyes, different from the males and young that have dark brown eyes.


Geographic range: The bushtit is commonly found in western North America, along the west coast from Mexico through the United States, and to the northern parts of British Columbia.


Habitat: The bushtit most commonly inhabits deciduous forests, where trees undergo seasonal change, and mixed woodlands, as well as parks and gardens. They can be found in suburbs and even in cities within their range.


Diet: As with other family members, the bushtit is primarily an insectivore, feeding on insects and spiders, as well as occasionally eating fruit and berries.


Behavior and reproduction: Bushtits are social birds that tend to live and travel in large flocks. They roost together, especially during the winter when they attempt to conserve body heat by huddling together. When spring arrives, the young leave the larger flock to establish their own colonies in another territory. Their song is a high thin call that resembles a buzzy, excited twittering sound. Some also are known to have a thin, trilled sort of call.

Breeding occurs from January to June, with courtships, mating behaviors, that are brief and include posturing, posing, and calling, with no particular song yet discovered. The nests they create are elaborate—a pendant nest that resembles a pocket. They can take from two weeks to almost two months to complete. Nests are hung from a hood of a woven spider web, which is hanging from a branch. They are monogamous (muh-NAH-guh-mus), having only one mate, with both male and female building the nest. Should the pair be disturbed while they are in the process of nest building, or laying or incubating, sitting on, eggs, it is not uncommon that they leave the nest site, even change mates, and build a new nest. The incubation of the eggs lasts for twelve days and is done by both sexes, with both of the pair roosting on the eggs in the nest at night. Each clutch averages five to seven eggs. The young are altricial (al-TRISH-uhl), helpless, blind and naked when hatched. The young stay in the nest for fourteen to fifteen days and are fed by both sexes. Sometimes helpers are present in caring for the young, but rarely are they from a previous brood. They have two broods a year.


Bushtits and people: Bushtits provide interesting entertainment to people and birdwatchers due to their cute appearance and fluffing of their feathers.


Conservation status: This species is not threatened, and has been known to be increasing in population in certain areas of its range. ∎


FOR MORE INFORMATION

Books:

Alsop, Fred J. III. Birds of North America. London and New York: DK Publishing, 2001.

Campbell, Bruce, and Elizabeth Lack, eds. A Dictionary of Birds. Vermillion, SD: Buteo Books, 1985.

Elphick, Chris, John B. Dunning Jr., and David Allen Sibley, eds. The Sibley Guide to Bird Life & Behavior. New York: Alfred A. Knopf, Inc., 2001.


Web sites:

"Bushtit Psaltriparus minimus." BirdWeb: Seattle Audubon's Online Guide to the Birds of Washington State. http://www.birdweb.org/birdweb/species.asp?id=332 (accessed on June 20, 2004).

"Family Aegithalidae (Long-tailed Tits)." University of Michigan Museum of Zoology Animal Diversity Web. http://animaldiversity.ummz.umich.edu/site/accounts/classification/Aegithalidae.html (accessed on June 20, 2004).

"Long-tailed Tits (Aegithalidae)." Bird Families of the World. http://www.montereybay.com/creagrus/longtailedtits.html (accessed on June 20, 2004).

Michaels, Patricia A. "Bushtit (Aegithalidae) Picture and ID." Green Nature. http://greennature.com/article908.html (accessed on June 20, 2004).