Chimney Swift, Purple Martin and Swallows
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Wildlife Note — 53 LDR0103 Chimney Swift, Purple Martin and Swallows Chimney Swift by Chuck Fergus Swifts, martins and swallows are built for life in the air. They have long tapering wings and light- weight bodies. Their short, wide bills open to expose gap- Chimney Swift (Chaetura pelagica) — The common ing mouths for scooping up insect prey. The chimney swift name comes from the bird’s favorite nesting habitat and belongs to Family Apodidae, with 90 species worldwide. the speed of its flight. A chimney swift is sooty gray, about The purple martin and the swallows are in Family five inches long, and has a one-foot wingspan; the body Hirundinidae, also with about 90 species around the looks stubby between the long, narrow wings. The bird globe. The chimney swift has tiny, vestigial feet with four spends most of the daytime hours in the air; its flight is clawed toes facing forward, letting it cling to upright sur- bat-like, with shallow wingbeats and erratic stalls and faces; the feet of the purple martin and the swallows have turns as the bird singles out insects or sweeps through three toes forward and one to the rear, for perching on clouds of prey. A loud clicking call is uttered in flight. branches and wires. Chimney swifts eat flies, leafhoppers, flying ants, may- Many of these birds are social and breed in colonies. flies, stoneflies, beetles, leaf bugs and other flying insects. Purple martins usually nest in artificial boxes with mul- They take spiders, mainly small ones floating on strands tiple chambers, put up by people wanting to attract these of silk borne aloft by air currents. Chimney swifts drink insect eaters; the other swallows build or occupy differ- on the wing, skimming low over ponds, and they even ent sorts of nests, depending on their species. Most swal- gather materials for their nests while in flight, using their lows do not defend territories. The males sing mainly to feet to break tips off dead branches and carry them back attract and communicate with females. Both parents usu- to the nest site. ally share in incubating eggs and feeding young. Swifts, Chimney swifts are thought to be monogamous and martins and swallows often forage in groups, soaring to mate for life. Pairs sometimes glide in tandem with above forests, farms and urban areas. During wet weather their wings raised in a V. In the past, chimney swifts nested they hunt at lower altitudes, where insects fly under damp in hollow trees and caverns. Today they use manmade conditions. These birds undertake long migrations. The structures almost exclusively: factory and house chim- seven species that breed in Pennsylvania winter in the neys, silos, air shafts and old wells, where they are pro- Gulf states, Central America and South America. tected from storms and predators. The nest is shaped like a half-saucer and cemented to a vertical surface, the twigs Tree Swallow (Tachycineta bicolor) — Tree swallows held together by the adults’ glutinous saliva, which so- nest across Canada and most of the northern United lidifies and binds as it dries. Females lay three to six eggs States. They are five to six inches long, an iridescent (four or five are usual), which are white and unmarked. green-black or blue-black above and bright white be- Both sexes participate in the 18- to 21-day incubation. low. They nest in tree cavities, woodpecker holes and The newly hatched young are altricial and are fed regur- bluebird houses put up by humans. The gitated insects. Sometimes a third “parent,” probably a earliest of our swallows to return yearling offspring of the adults, helps to feed and brood north, they arrive in late March Tree Swallow nestlings. The young fledge a month after hatching and and April; unlike the other join feeding flocks. In late summer swifts gather in the species, tree swallows evening before flying into large factory chimneys, where switch to eating ber- they roost by the thousands. ries and seeds to Chimney swifts are not common in the densely survive cold wooded parts of Pennsylvania, where trees may not be periods when mature enough to offer cavities for nesting and roosting. insects become Swifts arrive in the Northeast in May, raise a single brood torpid. They of- in June and July, and head south in August and Septem- ten breed near ber. They winter mainly in the Amazon Basin. The aver- the still waters of age lifespan is four years. lakes, ponds and marshes, compet- Purple Martin (Progne subis) — At eight inches in ing for nest cavi- length, the martin is the largest North American swal- ties with blue- low. Adult males are a glistening blue-black; females and birds, starlings, yearlings are grayish with pale bellies. Both sexes have a house sparrows and notched tail. Martins, less maneuverable than other swal- house wrens. Orni- lows, glide in circles punctuated with short periods of thologists believe flapping flight. Before Europeans came to the New World, that individuals native Americans were hanging gourds around their vil- choose new mates lages to attract purple martins, which also nested in caves each year. Tree swal- and hollow trees. In lows are more aggres- Pennsylvania today, sive than other swal- the vast majority low species and defend of martins nest an area within a radius colonially in of about 15 yards from the nest. The female lines the nest cavity with grass, weeds, rootlets and pine needles; after the four to seven pink- ish-white eggs are laid, she often adds feathers (usually white ones) from other birds. Incubation takes 14 to 15 days. The young fledge three weeks after hatching. Tree swallows migrate in flocks to wintering grounds in the Gulf states and Cen- tral America. Northern Rough-winged Swallow (Stelgidopteryx serripennis) — This small Purple Martin (body length, about five inches), nondescript brown and white compartmented swallow is named boxes that people put up for them. Martins for small serra- inhabit open areas near water, meadows and farmland. tions in its outer- They feed on winged ants, wasps, bees, flies, dragonflies, most wing feath- beetles, moths and butterflies. Males arrive first in the ers. The species spring, followed by females. The call is a throaty, gur- breeds across the gling tchew-wew. One male may mate with more than one United States and female. The four or five eggs are white and unmarked, in Central laid on a nest of grass, twigs and leaves inside the nest America. Rough-winged Northern chamber. Flocks of martins gather by the thousands in swallows often forage in August and September prior to migration. The female flight above moving water. Rough- incubates them for 15 to 18 days. The species winters in The call is a short, harsh trit winged the Amazon Basin. bit. The birds nest in cavi- Swallow ties in rock faces, quarries and stream banks, frequently instance, 800 nests were clustered on the side of a barn. in abandoned kingfisher burrows, drainpipes and culverts; The adults line the inside of the nest with grass, hair and sometimes they excavate their own burrows. At the end feathers. The three to six eggs are white spotted with of a one- to six-foot tunnel, the birds heap up twigs, bark, brown. Both sexes incubate for about 15 days. A female roots and weeds, and line a central cup with fine grasses. cliff swallow will sometimes lay an egg in another swallow’s The four to eight pure white eggs hatch after about 16 nest, or carry an egg in her bill to a neighboring nest. Cliff days of incubation. Rough-winged swallows nest through- swallows winter in southern South America. The popula- out Pennsylvania, rarely in colonies. They winter along tion is thought to be increasing in North America. the Gulf Coast and in Central America. Barn Swallow (Hirundo rustica) — The flight of these Bank Swallow (Riparia riparia) — About 5½ inches sleek, long-tailed blue-and-buff swallows can look like long, this small brown-backed swallow has a dark band an aerial ballet, with the birds sideslipping, stalling, twist- across its pale breast. Although they have small feet and ing and turning low over water or fields in pursuit of their tiny bills, bank swallows usually dig their own burrows, prey: house flies, horse up to five feet deep in dirt banks, piles of gravel or sand flies, beetles, wasps, and roadcuts. Nest entries of neighboring pairs may be bees, winged ants and Barn Swallow only a foot apart. Colonies arise and die out as banks of others. In bad suitable burrowing weather, barn swal- materials be- lows may land and come available eat spiders, snails, Bank Swallow and then lose berries or seeds. qualities that Pairs nest on bank swallows their own, or near require, such a few other pairs. as steepness Barn swallows and height. are common, Bank swallows abundant breed- forage over ing birds in Penn- fields and wet- sylvania and the lands and along Northeast. They rivers and ponds, build bowl- taking flies, shaped nests out beetles, wasps, of mud and winged ants, drag- straw, fixing them onflies, stoneflies, to walls, beams and moths and other flying insects. They nest from May until eaves of barns and July. The clutch averages four or five eggs. In late sum- other outbuildings; in mer bank swallows may gather in large flocks before de- culverts and under bridges; and rarely on the cliff faces parting for wintering grounds in South America. The spe- and caves which were the species’ original habitat before cies also breeds in Europe and Asia, where Europeans settled North America.