Chordeiles acutipennislesser nighthawk

Last updated:

Geographic Range

Chordeiles acutipennis ranges in small numbers from parts of California and Nevada, to larger populations in southern New Mexico, Arizona, and Texas.

(Sauer, 1997)

Habitat

The Lesser Nighthawk prefers large open areas. They like relatively level topography and naturally open land, as opposed to disturbed open lands with weeds. They are ground nesters. They make their nest on vernal pool soils in large, open areas with low human and pet disturbances. (PRBO, 1965)

Physical Description

The adult Lesser Nighthawk averages twenty centimeters in length. It has a short bill, and the upper parts of the body have a gray and white patterning. Its head and chest are brown, with white patterning. The underside of the bird has dark bars that run across its stomach. The wings are dark with conspicuous pale patches on the bend of the wing. The tail has thin white bars across the top. An adult male will have a white throat, while the female will have a buff throat and buff spots on inner parts of the wings.

(Robbins et al. 1966)

Reproduction

Lesser Nighthawks breed from early spring to mid summer. The females lay two speckled eggs in a nest constructed on the ground or on a gravel rooftop. The mother will incubate the eggs for eighteen to twenty days. Once hatched, the mother brings food to the newborn nighthawks. Once able to fly, the young nighthawks leave the nest and their mother. (Sauer, 1997)

Behavior

The Lesser Nighthawk is nocturnal. It ranges far on its nightly forays for food and social interaction. A crucial element for a nesting nighthawk is the seclusion from human disturbance. The Lesser Nighthawk will flush the ground when an intruder approaches within a few meters of their nest. They then perform a low circling flight with accentuated wing beats. Nighthawks mostly nest in May or June, which is later than most lowland species. Males attract females using a series of calls. (Robbins et al., 1966)

Communication and Perception

Food Habits

The diet of the Lesser Nighthawk includes small insects such as winged ants, mosquitoes, beetles, moths, and grasshoppers. They catch these insects while flying high in the air, and near trees and brush along springs and streams. (Bent 1940; Harrison 1978)

Economic Importance for Humans: Positive

The Lesser Nighthawk helps to keep the insect population under control. These are a very rare bird to see, making them desirable for bird watchers to see and photograph. (Bent 1940; Harrison 1978)

Economic Importance for Humans: Negative

The Lesser Nighthawk does not have any negative influences on humans or the environment.

Conservation Status

The conservation status of the Lesser Nighthawk is uncertain near the Pacific coast. From the Mexican border to the San Joaquin Valley, the bird is scarce. Most of its natural habitat has already been lost. (Lovio, 1998)

Contributors

Patrick Phillips (author), Milford High School, George Campbell (editor), Milford High School.

Glossary

Nearctic

living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.

World Map

acoustic

uses sound to communicate

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

chemical

uses smells or other chemicals to communicate

desert or dunes

in deserts low (less than 30 cm per year) and unpredictable rainfall results in landscapes dominated by plants and animals adapted to aridity. Vegetation is typically sparse, though spectacular blooms may occur following rain. Deserts can be cold or warm and daily temperates typically fluctuate. In dune areas vegetation is also sparse and conditions are dry. This is because sand does not hold water well so little is available to plants. In dunes near seas and oceans this is compounded by the influence of salt in the air and soil. Salt limits the ability of plants to take up water through their roots.

endothermic

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

motile

having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

oviparous

reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

tactile

uses touch to communicate

threatened

The term is used in the 1994 IUCN Red List of Threatened Animals to refer collectively to species categorized as Endangered (E), Vulnerable (V), Rare (R), Indeterminate (I), or Insufficiently Known (K) and in the 1996 IUCN Red List of Threatened Animals to refer collectively to species categorized as Critically Endangered (CR), Endangered (EN), or Vulnerable (VU).

visual

uses sight to communicate

References

Bent, A., C. Harrison. 1940 and 1978. "California Wildlife Habitat Relationships Systems" (On-line). Accessed (Date Unknown) at http://www.dgf.ca.gov.

Knopf, A. 2000. "Nature Guides" (On-line). Accessed (Date Unknown) at http://www.eNature.com.

Lovio, J. 1998. "San Diego County Bird Atlas" (On-line). Accessed (Date Unknown) at http://www.sdnhm.org.

Point Reyes Bird Observatory, 1965. "Point Reyes Bird Observatory" (On-line). Accessed (Date Unknown) at http://www.prbo.org.

Robbins, C., B. Bruun, H. Zim. 1966. "U.S. Geological Survey" (On-line). Accessed (Date Unknown) at http://www.usgs.gov.

Sauer, J. 7/29/97. "USGS Science for a changing world" (On-line). Accessed (Date Unknown) at http://www.mbr-pwrc.usgs.gov.