Common Nighthawk

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(New page: Image:CommonNighthawk.jpg '''Common Name:''' Common Nighthawk<br> '''Scientific Name:''' Chordeiles minor '''Size:''' 8.7-9.8 inches (22-25 cm); '''Wingspan:''' 20-24 inches (51 to 6...)
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Revision as of 22:16, 7 December 2015


Common Name: Common Nighthawk
Scientific Name: Chordeiles minor

Size: 8.7-9.8 inches (22-25 cm); Wingspan: 20-24 inches (51 to 61 cm)

Habitat: The Americas; summering in North America and wintering in South America. They migrate by day or night in loose flocks; frequently numbering in the thousands,no visible leader has been observed. The enormous distance traveled between breeding grounds and wintering range is one of North America's longer migrations. The northbound journey commences at the end of February and the birds reach destinations as late as mid-June. The southbound migration commences mid-July and reaches a close in early October.

Common Nighthawks, which have one of the longest migration routes of all North American birds, sometimes show up far out of range. They have been recorded in Iceland, Greenland, the Azores, the Faroe Islands, and multiple times on the British Isles.

The common nighthawk may be found in forests, desert, savannas, beach and desert scrub, cities, and prairies, at elevations of sea level or below to 3,000 m (9,800 ft). They are one of a handful of birds that are known to inhabit recently burned forests, and then dwindle in numbers as successional growth occurs over the succeeding years or decades. It is also drawn into urban built-up areas by insects.

Status: Least Concern. Global population: 16,000,000 adult individuals with a decreasing population trend. Common Nighthawk populations declined by almost 2 percent per year between 1966 and 2010, amounting to a cumulative decline of 59 percent, according to the North American Breeding Bird Survey. Canadian populations experienced declines of up to 4 percent, and recent data suggest the species’ numbers may have dropped by as much as half in Canada since the mid-1960s. Hard numbers are difficult to come by because the Common Nighthawk's cryptic colors and nearly nocturnal habits make them difficult to count during standardized surveys. Partners in Flight estimates the global breeding population at 16 million, with 88 percent breeding in the U.S., 5 percent in Canada, and 4 percent in Mexico. The 2014 State of the Birds Report listed them as a Common Bird in Steep Decline, and they rate a 11 out of 20 on the Partners in Flight Continental Concern Score. Across North America, threats include reduction in mosquitoes and other aerial insects due to pesticides, and habitat loss including open woods in rural areas and flat gravel rooftops in urban ones. Nighthawks are also vulnerable to being hit by cars as they forage over roads or roost on roadways at night. People have had some success creating nesting habitat by placing gravel pads in the corners of rubberized roofs and by burning and clearing patches of forest to create open nesting sites.

Diet: Twlight-hour flying insects are its preferred food source. The hunt ends as dusk becomes night, and resumes when night becomes dawn. Nighttime feeding (in complete darkness) is rare, even on evenings with a full moon. The bird displays opportunistic feeding tendencies, although it may be able to fine-tune its meal choice in the moments before capture.

Nesting: Adults have a large, flattened head with large eyes; facially it lacks rictal bristles. They have long slender wings that at rest extend beyond a notched tail. There is noticeable barring on the sides and abdomen, also white wing-patches. In the yearly molt, all bodily plumage and rectrices are replaced in the post-juvenile molt. This molt commences in September at the breeding grounds; the majority of the body plumage is replaced but wing-coverts and rectrices are not completed until January–February, once the bird arrives at the wintering grounds. There is no other molt prior to the annual molt of the adult.

The female probably selects the nest site, usually on unsheltered ground, gravel beaches, rocky outcrops, and open forest floors. Nests are typically out in the open, but may also be near logs, boulders, grass clumps, shrubs, or debris. In cities, Common Nighthawks nest on flat gravel roofs. They lay eggs directly on the ground, which may consist of gravel, sand, bare rock, wood chips, leaves, needles, slag, tar paper, cinders, or living vegetation, such as moss, dandelion rosettes, and lichens. Usually 2 eggs are laid and incubated for 16 to 20 days. Cool Facts: Many Late Pleistocene fossils of Common Nighthawks, up to about 400,000 years old, have been unearthed between Virginia and California and from Wyoming to Texas. While the Common Nighthawk is arguably the most studied nightjar in North America and one of the best known in the world, the Common Nighthawk remains poorly understood. Most studies of this species have been short-term and anecdotal in nature and specific data about much of its life history remain scarce, particularly from the southern part of its breeding range and especially from its South American wintering grounds.

The common nighthawk is sometimes called a "bull-bat", due to its perceived "bat-like" flight, and the "bull-like" boom made by its wings as it pulls from a dive. Another name is "goatsucker", from an archaic, erroneous idea that the birds would fly into barns at night and suck dry the teats of goats.

Nighthawks fly in looping patterns in mornings and evenings. During the day, they roost motionless on a tree branch, fencepost, or the ground and are very difficult to see. When migrating or feeding over insect-rich areas such as lakes or well-lit billboards, nighthawks may gather in large flocks. Their buzzy, American Woodcock-like ‘peent’ call is distinctive.

There are 9 currently recognized subspecies:

  • C. m. aserriensis. First reported by Cherrie in1896: breeds from south central Texas to north Mexico. It is darker than C. m. sennetti and paler and less cinnamon than C. m. henryi.
  • C. m. chapmani. First reported by Coues in 1888. It breeds from southeast Kansas to east North Carolina and southwards to south east Texas and south Florida. It is the darkest of the subspecies.
  • C. m. henryi. First reported by Cassin in 1855. It breeds from south east Utah and south west Colorado through mountains of west Texas, Arizona and New Mexico (less north east) to east Sonora, Chihuahua, and Durango. It is unique with ochraceous to deep cinnamon feather edges on upper parts.
  • C. m. hesperis. First reported by Grinnell in 1905. It breeds in south west Canada (British Columbia and Alberta), the western interior of United States (Washington, Montana, Nevada, interior California, Utah, extreme north Colorado, west Wyoming). It is darker than C. m. sennetti and paler and less cinnamon than C. m. henryi.
  • C. m. howelli. First reported by Oberholser in 1914. It breeds in west central United States (north Texas, west Oklahoma, and Kansas to east Colorado, less typical form in central Colorado, north east Utah and Wyoming). It is darker than C. m. sennetti and paler and less cinnamon than C. m. henryi.
  • C. m. minor. First reported by J.R. Forster in 1771. The nominate species breeds from south east Alaska to Vancouver Island, British Columbia, Canada, and south Canada/northern United States (Minnesota, Indiana) to Virginia, North Carolina, Georgia and Oklahoma. Considered by some as the darkest subspecies.
  • C. m. neotropicalis. First reported by Selander & Alvarez del Toro in 1955. It breeds in south Mexico and Honduras.
  • C. m. panamensis. First reported by Eisenmann in 1962. It breeds on the Pacific slope of Panama and north west Costa Rica. It is noted to depart Panama during winter for points in South America.
  • C. m. sennetti. First reported by Coues in 1888. It breeds in the north Great Plains: east Montana, south Saskatchewan, Manitoba, southwards to North Dakota, Minnesota and Iowa. It is the palest of the subspecies.

Nighthawks have a life span of 4 to 5 years; the oldest Common Nighthawk on record was 10 years old.

Found in Songbird ReMix Frogmouths, Nightjars & Goatsuckers

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