Animal Diversity Web

Ge­o­graphic Range

Chuck-will's-wid­ows breed in suit­able habi­tat through­out the south­east­ern United States, from Florida to Long Is­land, New York and west to Kansas, Ok­la­homa, and east­ern Texas. They also breed in iso­lated areas of south­ern On­tario, north­west­ern In­di­ana along Lake Michi­gan, and in cen­tral and south­ern Ohio. They win­ter mainly in Cen­tral Amer­ica from Tamauli­pas, Mex­ico south to Colom­bia east of the Andes and in the An­tilles Is­lands. They also win­ter in south­ern Florida and oc­ca­sion­ally along the Gulf of Mex­ico in Texas, Louisiana, and Al­abama. They have been re­ported in areas north of their breed­ing range as well, as far north as the Cana­dian mar­itime provinces and north­ern Cal­i­for­nia. (Straight and Cooper, 2000)

• Biogeographic Regions
• nearctic
  • native

Habi­tat

Chuck-will's-wid­ows are found in open wood­lands, in­clud­ing de­cid­u­ous, mixed, pine (Pinus), and oak-hick­ory (Quer­cus-Carya) forests. Open­ings and edges are im­por­tant habi­tat fea­tures and these birds can be found in sub­ur­ban areas with the ap­pro­pri­ate char­ac­ter­is­tics. Where they co-oc­cur with whip­poor­wills (Caprimul­gus vo­ciferus), Chuck-will's-wid­ows are found in more open habi­tats. Dur­ing mi­gra­tion and in win­ter they can be found in a wider va­ri­ety of forested habi­tats and scrub­lands, in­clud­ing mixed agri­cul­ture areas. They have been found at el­e­va­tions up to 2600 m in Colom­bia. (Straight and Cooper, 2000)

• Habitat Regions
• temperate
• tropical
• terrestrial

• Terrestrial Biomes
• forest
• scrub forest

• Other Habitat Features
• suburban
• agricultural
• riparian

• Range elevation

  0 to 2600 m

  0.00 to 8530.18 ft

Phys­i­cal De­scrip­tion

Chuck-will's-wid­ows are larger than their well-known cousins, whip-poor-wills (Caprimul­gus vo­ciferus), but sim­i­lar in over­all ap­pear­ance. They are the largest species of night­jar in North Amer­ica. Chuck-will's-wid­ows are cryp­ti­cally col­ored in mot­tled, cin­na­mon-brown, cream, and black feath­ers that help to cam­ou­flage them when they roost dur­ing the day on tree branches or the ground. They are from 28 to 32 cm long, with wings from 20 to 22.5 cm long, and weigh­ing ap­prox­i­mately 110 g. Their tails are long, pro­ject­ing be­yond the wings when they are at rest, from 12.8 to 15.1 cm long. Males have white on the outer 3 tail feath­ers and a ru­fous with white col­lar on the throat. Fe­males have a buffy col­lar on the throat and lack the white on their tail feath­ers. Males are also slightly larger than fe­males. Im­ma­ture in­di­vid­u­als re­sem­ble fe­males and there is no sea­sonal vari­a­tion in plumage. No sub­species are rec­og­nized. Chuck-will's-wid­ows are most often rec­og­nized by their voice, they are rarely seen. Chuck-will's-wid­ows may hi­ber­nate like their west­ern cousins, poor­wills (Pha­laenop­tilus nut­tal­lii), but this has yet to be con­firmed. (Straight and Cooper, 2000)

• Other Physical Features
• endothermic
• bilateral symmetry

• Sexual Dimorphism
• male larger
• sexes colored or patterned differently

• Average mass

  110 g

  3.88 oz

• Range length

  28 to 32 cm

  11.02 to 12.60 in

Re­pro­duc­tion

Chuck-will's-widow males de­fend mat­ing ter­ri­to­ries, chas­ing other males away. They use their songs to at­tract fe­males and ad­ver­tise ter­ri­to­ries. Males also per­form courtship dis­plays where they spread their tail, puff them­selves up, drop the wings, and hop around on the ground near the fe­male, com­ing along­side her when fin­ished. They may also growl and "dance" near a fe­male. There is some ev­i­dence that males and fe­males re­join to breed again from year to year in the same place. (Straight and Cooper, 2000)

• Mating System
• monogamous

Most pop­u­la­tions ar­rive on breed­ing grounds in March and begin breed­ing in April. Pairs form within 10 days of fe­males ar­riv­ing on the breed­ing grounds. Fe­males lay one neu­tral col­ored egg every other day for 3 days, re­sult­ing in a clutch size of 2 (al­though 1 to 4 is pos­si­ble). Eggs are laid in a sim­ple scrape on the ground, usu­ally under some kind of veg­e­ta­tion. In­cu­ba­tion takes 20 days and starts with the first egg laid. Adults do not flush eas­ily from nests, pos­si­bly be­cause their cryp­tic col­ors help to cam­ou­flage the eggs and young. There is no in­for­ma­tion on how long nestlings or fledg­lings are de­pen­dent on par­ents, but es­ti­mates based on whip­poor­wills (Caprimul­gus vo­ciferus) and nighthawks (Chordeiles minor) sug­gest young are de­pen­dent on par­ents for about 50 days after hatch­ing. They can fly at 17 days and re­main de­pen­dent on par­ents for an­other 14 days. Chuck-will's-wid­ows will con­tinue to re­place eggs or clutches that are preyed on up to 4 times in a sea­son but gen­er­ally raise only 1 brood each year. The age of sex­ual ma­tu­rity is not known. (Straight and Cooper, 2000)

• Key Reproductive Features
• iteroparous
• seasonal breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual
• oviparous

• Breeding interval

  Chuck-will's-widows breed once yearly.

• Breeding season

  Chuck-will's-widows breed from April through June.

• Range eggs per season

  1 to 4

• Average eggs per season

  2

• Average time to hatching

  20 days

• Average fledging age

  17 days

• Average time to independence

  14 days

Fe­males only de­velop an in­cu­ba­tion patch, but males have also been ob­served in­cu­bat­ing eggs. Both adults are pro­tec­tive of the nest. Some ev­i­dence sug­gests males may feed fe­males on the nest. Young are al­tri­cial at hatch­ing, can fly at 17 days, and re­main de­pen­dent on adults for an­other 14 days after fledg­ing. (Straight and Cooper, 2000)

• Parental Investment
• altricial
• pre-fertilization
  • provisioning
  • protecting
    • female
• pre-hatching/birth
  • provisioning
    • female
  • protecting
    • male
    • female
• pre-weaning/fledging
  • provisioning
    • male
    • female
  • protecting
    • male
    • female
• pre-independence
  • provisioning
    • male
    • female
  • protecting
    • male
    • female

Lifes­pan/Longevity

There is lit­tle in­for­ma­tion on lifes­pan in Chuck-will's-wid­ows, the longevity record based on band­ing is 14 years and 10 months old. (Straight and Cooper, 2000)

• Range lifespan
  Status: wild

  14.83 (high) years

Be­hav­ior

Not much is known about be­hav­ior in Chuck-will's-wid­ows be­cause of their very ef­fec­tive cryp­sis and their noc­tur­nal habits. There has been lit­tle re­search done on these night­jars. They fly silently from a few to 20 me­ters above ground and may dive to grab in­sects. They roost along tree branches or on the ground among veg­e­ta­tion. Chuck-will's-wid­ows are cre­pus­cu­lar and ac­tive on nights with suf­fi­cient moon­light. They are usu­ally soli­tary, ex­cept in fam­ily groups after nest­ing and in groups dur­ing mi­gra­tion. (Straight and Cooper, 2000)

Chuck-will's-wid­ows are mi­gra­tory, with the ex­cep­tion of pop­u­la­tions in south­ern Florida and along the Gulf of Mex­ico in Texas, Louisiana, and Al­abama. In spring they begin mi­grat­ing from Feb­ru­ary to May, with most pop­u­la­tions ar­riv­ing on the breed­ing grounds in March and April. De­par­ture from the breed­ing grounds is es­ti­mated to occur from late Au­gust through Oc­to­ber. Chuck-will's-wid­ows don't call dur­ing mi­gra­tion, so mi­gra­tory be­hav­ior is based on rel­a­tively few ob­ser­va­tions. (Straight and Cooper, 2000)

• Key Behaviors
• flies
• nocturnal
• motile
• migratory
• solitary

Home Range

Home range sizes in Chuck-will's-wid­ows aren't known, but den­si­ties have been recorded up to 30 birds per 40 hectares.

Com­mu­ni­ca­tion and Per­cep­tion

Chuck-will's-wid­ows get their com­mon name from the sound of their call, which often has the em­pha­sis on the 2nd and 3rd syl­la­ble. Much of what we know about Chuck-will's-wid­ows comes from de­tect­ing them through their vo­cal­iza­tions. Their noc­tur­nal habits and cryp­tic col­ors make them dif­fi­cult to ob­serve. Males sing from 16 to 30 times per minute from a perch, fe­males don't sing but may an­swer muted calls from males on the nest. Males sing through courtship, dis­con­tinue singing dur­ing the nest­ing pe­riod, and begin to sing again be­fore fall mi­gra­tion. Songs occur at dusk and when the moon is out, more singing oc­curs on warmer nights. Songs are thought to be to at­tract mates and ad­ver­tise a breed­ing ter­ri­tory. Chuck-will's-wid­ows also have dif­fer­ent kinds of calls used when star­tled or in ter­ri­to­r­ial de­fense. They also hiss when threat­ened. (Straight and Cooper, 2000)

• Communication Channels
• acoustic

• Perception Channels
• visual
• tactile
• acoustic
• chemical

Food Habits

Chuck-will's-wid­ows eat noc­tur­nal fly­ing in­sects, es­pe­cially bee­tles and moths, es­pe­cially geometrid moths (Geometri­dae). They fly just above the ground, often along wood­land edges, to cap­ture in­sects in their large mouths. They may also for­age over water or fly out to cap­ture pass­ing in­sects from perches. They for­age mainly at dusk and dawn and when there is suf­fi­cient moon­light for low-light vi­sual de­tec­tion of fly­ing in­sects. Chuck-will's-wid­ows use their ric­tal bris­tles, the bris­tles around their mouths, to scoop up in­sects. They may also for­age on the ground for in­sects or frogs, es­pe­cially when they are molt­ing, and they some­times pur­sue and cap­ture small birds, in­clud­ing palm war­blers (Den­droica pal­marum), yel­low war­blers (Den­droica pe­techia), worm-eat­ing war­blers (Helmitheros), hooded war­blers (Wilso­nia cit­rina), swamp spar­rows (Melospiza geor­giana), Car­olina wrens (Thryotho­rus lu­dovi­cianus), Cuban emer­alds (Chloros­til­bon ri­cordii), com­mon yel­lowthroats (Ge­oth­lypis trichas), and Cape May war­blers (Den­droica tig­rina). Chuck-will's-wid­ows are often ob­served on roads where they col­lect rocks, pre­sum­ably to help them grind and di­gest their in­sect prey. (Straight and Cooper, 2000)

• Primary Diet
• carnivore
  • insectivore

• Animal Foods
• birds
• amphibians
• insects

Pre­da­tion

Their cryp­tic col­oration and noc­tur­nal­ity make Chuck-will's-wid­ows less vul­ner­a­ble to pre­da­tion, al­though their ground-nest­ing habits make them some­what vul­ner­a­ble to ter­res­trial preda­tors. There is lit­tle in­for­ma­tion on pre­da­tion on Chuck-will's-wid­ows, but snakes and mam­malian preda­tors are sus­pected nest preda­tors. When dis­turbed near a nest, adults will at­tack a threat or per­form a dis­trac­tion dis­play, such as drag­ging their wings on the ground as they walk away while hiss­ing. (Straight and Cooper, 2000)

• Anti-predator Adaptations
• cryptic

Ecosys­tem Roles

Chuck-will's-wid­ows are im­por­tant preda­tors of night-fly­ing in­sects, fill­ing a sim­i­lar eco­log­i­cal role to large, in­sec­tiv­o­rous bats. Two species of louse flies are known to par­a­sitize nests (Pseudolynchia brun­nea and Pseudolynchia ru­fipes). (Straight and Cooper, 2000)

Eco­nomic Im­por­tance for Hu­mans: Pos­i­tive

Chuck-will's-wid­ows may help to con­trol in­sect pest pop­u­la­tions.

• Positive Impacts
• controls pest population

Eco­nomic Im­por­tance for Hu­mans: Neg­a­tive

There are no known ad­verse ef­fects of Caprimul­gus car­o­li­nen­sis on hu­mans.

Con­ser­va­tion Sta­tus

Chuck-will's-widow pop­u­la­tions seem to be de­clin­ing in the east­ern United States, al­though there may be in­suf­fi­cient data to draw con­clu­sions. They may be vul­ner­a­ble to pes­ti­cides that af­fect their in­sect prey and mor­tal­ity oc­curs when they are hit by cars as they land on roads to col­lect peb­bles. Habi­tat changes may be caus­ing whip­poor­wills (Caprimul­gus vo­ciferus) to ex­pand their range, po­ten­tially im­pact­ing Caprimul­gus car­o­li­nen­sis) pop­u­la­tions. (Straight and Cooper, 2000)

• IUCN Red List

  Least Concern
  More information

• IUCN Red List

  Least Concern
  More information

• US Migratory Bird Act

  Protected

• US Federal List

  No special status

• CITES

  No special status

• State of Michigan List

  No special status

Other Com­ments

Chuck-will's-wid­ows are thought to be most closely re­lated to ru­fous night­jars (Caprimul­gus rufus) in the genus Caprimul­gus. They have sim­i­lar plumage and vo­cal­iza­tions. Some have sug­gested, based on mor­phol­ogy, that Chuck-will's-wid­ows should be placed in their own genus: Antros­to­mus. (Straight and Cooper, 2000)

Con­trib­u­tors

Tanya Dewey (au­thor), An­i­mal Di­ver­sity Web.

Ref­er­ences

Straight, C., R. Cooper. 2000. Chuck-will's-widow (Caprimul­gus car­o­li­nen­sis). The Birds of North Amer­ica On­line, 499: 1-20. Ac­cessed May 06, 2009 at http://​bna.​birds.​cornell.​edu/​bna/​species/​499.