Contopus virenseastern wood pewee(Also: eastern wood-pewee)

Geographic Range

The range of eastern wood-pewees (Contopus virens) includes eastern North America, south into South America. Eastern wood-pewees range from as far north as Regina, Saskatchewan and as far south as Sinop, Brazil. In North America, eastern wood-pewees are found as far east as Newfoundland and as far west as the Great Plains in the United States. In South America, eastern wood-pewees are found as far east as Brazil and as far west as the coast of Ecuador.

During breeding season, eastern wood-pewees primarily live in North America, in the central and eastern parts of the continent. Eastern wood-pewees overwinter in southern Peru and as far east as Brazil. (Campbell, et al., 2012; McCarty, 1996; Newell and Rodewald, 2012)

Habitat

Eastern wood-pewees inhabit multiple types of forest types in eastern North America. This can include both coniferous and deciduous forests - both young and mature stands. They can be found both in the upper or lower canopies of these trees. The dominant trees in the coniferous forests can be cedar-aspen, aspen-red maple, beech-maple, and pine-aspen trees. Deciduous forests' dominant trees can vary but pewees are more common in woodlots that contain more shrubs and lichens. Other forest types can include orchards, roadside trees, and other urban savannas. These birds can breed in all of these habitats, as well as riparian habitats.

Due to their wide geographic range, elevation has not been reported. (McCarty, 1996)

Physical Description

Eastern wood-pewees grow to an average length of 150 mm and reach an average weight of 14.1g as adults. The wingspan of eastern wood-peewees reaches a maximum of 26 cm (ranges: 23 to 26 cm). According to Rising and Schueler (1980), eastern wood-pewees have wing length that ranges from 84.0 to 79.8 mm and tail length that ranges from 65.7 to 63.5 mm. According to Lederer (1975), eastern wood-pewees have an average bill length of 10.6 mm, bill width of 6.3 mm, and a bill depth of 4.1 mm.

They are covered in greyish feathers with olive and yellow colors, and also have wing bars that are white and grey in color. The tips of their bill is black or dark-brown, while the base is orange-yellow. Their eyes are brown. Males and females look alike.

Hatchlings are altricial, born partly with down feathers. By late August or early September, the young have the full complement of adult feathers. Although birth mass has not been reported, young-of-the-year captured in September averaged 13.3 g (range 11 to 18.7g), while adults were larger, averaging 14.5 g (range 12.3 to 18.2g). (Kress and Wolfson, 2017; Lederer, 1975; McCarty, 1996; Rising and Schueler, 1980)

  • Sexual Dimorphism
  • sexes alike
  • Average mass
    14.1 g
    0.50 oz
  • Average length
    150 mm
    5.91 in
  • Range wingspan
    23 to 26 cm
    9.06 to 10.24 in

Reproduction

Eastern wood-pewees breed once a year usually between May through August. Male eastern wood-pewees tend to be polygynous, pairing with more than one female. Females tend to double brood, initiating a second clutch after successfully raising young from their first clutch. Males increase their productivity when they pair with more than one mate, as females increase their productivity when they double brood. Males tend to defend the nesting site and territory with certain song calls. Male eastern wood-pewees have been known to feed nestlings among two different nests if they are polygynous. Nests are always in trees, with a wide range of heights above ground (1 to 21 m). Across multiple studies, about half the nests are 5 to 10 m above the ground. The nests are the shape of a bowl, lines with lichens, grass, tree bark, fur, and more. It's suspected that nest-building takes several days, but it's unclear if males and females work together to build it. (Kendrick, et al., 2014; McCarty, 1996; Newell, et al., 2013)

Eastern wood-pewees breed seasonally during summer months (May through August) with peaks during early June and mid-July. Males defend the nest and territory by singing their song. Eastern wood-pewees have a clutch size of 3 eggs (range 2 to 4) per nest with each egg being laid on consecutive days. The nest is incubated for 12 to 13 days by the female, while males sometimes feeding the females on the nest. Nestlings fledge from 16 to 18 days after hatching.

Time to juvenile independence likely coincides with fledging. Parents may feed them after they leave the nest, but the number of days has not been reported. The nesting cycle of eastern wood-pewees averages 29 days and the females usually take 6 days to build each nest. (Kendrick, et al., 2014; McCarty, 1996; Newell, et al., 2013)

  • Breeding interval
    Eastern wood-pewees breed twice yearly
  • Breeding season
    Eastern wood-pewees breed from May to August
  • Range eggs per season
    2 to 4
  • Range time to hatching
    12 to 13 days
  • Range fledging age
    16 to 18 days

Both males and females are thought to contribute to nest-building, and the male will feed the female while she is incubating the eggs. Female eastern wood-pewees will brood atricial nestlings for four or five days until they are ready to begin eating a diet similar to adults. Once the nestlings are four or five days old the female will gather food such as insects and regurgitate the contents to feed to each nestling. Parents both feed the young until they fledge at 16 to 18 days, and presumably for a short time thereafter. (McCarty, 1996)

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

Lifespan/Longevity

Eastern wood-pewees have a maximum lifespan of 8.2 years in the wild. They are not known to be kept in captivity. ("BBL - Longevity Records of North American Birds", 2016)

  • Range lifespan
    Status: wild
    8.2 (high) years

Behavior

Eastern wood-pewees are a diurnal, social species and the males tend to attack other males during singing after altering their singing pattern. Male eastern wood-pewees are very territorial especially during breeding season; males may help raise two nests from two different females at once. Males tend to initiate interactions with females to begin their breeding season.

When they are migrating and on their winter grounds, individuals are solitary.

Eastern wood-pewees have a very unique song ("pee-ah-weee!" and "wee-ur!" or "wee-ooo!") and the females will alarm a song when a predator is in range to defend the nestlings. Females also respond to song playback in their territory from other members of the species. (McCarty, 1996)

  • Range territory size
    22000 to 77000 m^2

Home Range

Eastern wood-pewees are territorial during the breeding season, but not during the winter months. In the breeding season, two studies reported average territory sizes of 2.2 ha in Iowa and 7.7 ha in Wisconsin. Both were in forest matrices. (McCarty, 1996)

Communication and Perception

Eastern wood-pewees are most active during the daytime, beginning up to 45 minutes before sunrise and continuing through most of the day. They can also sing at night. Females typically do not sing. Males utter a song every few seconds with an up-tempo beat. The song can be sung in two forms, “pee-ah-weee” which is sung and repeated in strings, and “wee-ooo” or "wee-ur!" where the strings are separated without breaking the tempo of the performance of the song.

When male pewees were in the presence of other males, those singing at mid-length did not initiate or approach other interactions. Eastern wood-pewees that sung longer strings are usually initiated with flight creating more interactions among the species along with removing themselves from social interactions. When non-pewee species were present and calling, eastern wood-pewees often sung less and waited for the other species to finish singing.

At twilight, singing eastern wood-pewees are usually on the same perch in their territory or on a nearby perch. During the daytime, singing occurs at different sites. (Clark and Leung, 2011; McCarty, 1996; Smith, 1988)

Food Habits

Eastern wood-pewees are insectivores with a primary diet of flying insects that can be captured from perches in the subcanopy at an average height of 11 meters. The insects that eastern wood-pewees tend to consume are flies (Diptera), true bugs (Hemiptera), butterlies and moths (Lepidoptera), bees (Hymenoptera), beetles (Coleoptera), grasshoppers (Orthoptera), stoneflies (Plecoptera), and mayflies (Ephemeroptera). Spiders (Araneae) and dragonflies (Odonoata) are sometimes taken. They occasionally eats berries and seeds.

They can take insects on the fly or by gleaning (taking them off plants of off the ground). Nestlings are insectivorous, eating whatever the parents bring to them. (McCarty, 1996; Ridgely and Gwynne, 1989)

  • Animal Foods
  • insects
  • terrestrial non-insect arthropods
  • Plant Foods
  • seeds, grains, and nuts
  • fruit

Predation

Female eastern wood-pewees use a two-note call to alert other individuals that a predator is in range. Males are territorial and will chase or sometimes fight off other species to protect their territory. In periods where nest predation occurs, females will re-nest up to four times if the nest fails. Specific predators have not been reported, although Newell et al. (2013) mention other canopy songbirds as potential nest predators. (Newell, et al., 2013)

Ecosystem Roles

Eastern wood-pewees are parasitized by brown-headed cowbirds (Molothrus ater). Brown-headed cowbirds are brood-parasites, where the female does not make her own nests; instead, she lays her eggs in nests made by the pewees. (Underwood, et al., 2004)

Commensal/Parasitic Species

Economic Importance for Humans: Positive

Eastern wood-pewees positively impact humans through bird watching, as they are a common species in heavily-urbanized areas. (Sauer, et al., 2013)

Economic Importance for Humans: Negative

There are no negative impacts of eastern wood-pewees on humans.

Conservation Status

Eastern wood-pewees are listed at "Least Concern" by the IUCN Red List and have no special status on the US Federal List or international lists (CITES). The state of Michigan also lists eastern wood-pewees as no special status. Eastern wood-pewees are a protected species on the Migratory Bird list, and therefore, cannot be hunted or collected without a permit.

Threats to pewees are numerous, and include pesticides (affecting their prey), collisions with buildings, and overpopulation of white-tailed deer (Odocoileus virginianus). In the case of the deer, high deer densities are linked to lower breeding success in wood-pewees. The deer consume the understory where the pewees nest and forage. For this reason, conservation measures include a goal of deer densities less than 4-8 per square kilometer. Pewees also seem to benefit in coniferous forests that are managed by prescribed fire and thinning efforts, but they do poorly in clearcut areas. Although eastern wood-pewees have declined in number in the last 25 years, they are still believed to be common. (BirdLife International, 2016; McCarty, 1996)

Contributors

Whitney Clowser (author), Radford University, Alex Atwood (editor), Radford University, Karen Powers (editor), Radford University, Joshua Turner (editor), Radford University, Tanya Dewey (editor), University of Michigan-Ann Arbor.

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

Neotropical

living in the southern part of the New World. In other words, Central and South America.

World Map

acoustic

uses sound to communicate

altricial

young are born in a relatively underdeveloped state; they are unable to feed or care for themselves or locomote independently for a period of time after birth/hatching. In birds, naked and helpless after hatching.

arboreal

Referring to an animal that lives in trees; tree-climbing.

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.

carnivore

an animal that mainly eats meat

chemical

uses smells or other chemicals to communicate

diurnal
  1. active during the day, 2. lasting for one day.
ecotourism

humans benefit economically by promoting tourism that focuses on the appreciation of natural areas or animals. Ecotourism implies that there are existing programs that profit from the appreciation of natural areas or animals.

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.

female parental care

parental care is carried out by females

forest

forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.

insectivore

An animal that eats mainly insects or spiders.

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).

migratory

makes seasonal movements between breeding and wintering grounds

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.

polygynous

having more than one female as a mate at one time

riparian

Referring to something living or located adjacent to a waterbody (usually, but not always, a river or stream).

seasonal breeding

breeding is confined to a particular season

sexual

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

social

associates with others of its species; forms social groups.

solitary

lives alone

tactile

uses touch to communicate

temperate

that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).

territorial

defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement

urban

living in cities and large towns, landscapes dominated by human structures and activity.

visual

uses sight to communicate

References

2016. "BBL - Longevity Records of North American Birds" (On-line). Accessed October 25, 2017 at https://www.pwrc.usgs.gov/bbl/longevity/Longevity_main.cfm.

BirdLife International, 2016. "Contopus virens" (On-line). The IUCN Red List of Threatened Species 2016: e.T22699816A93749255. Accessed October 25, 2017 at http://www.iucnredlist.org/details/22699816/0.

Campbell, S., J. Witham, M. Hunter, Jr.. 2012. Long-Term changes in spatial distribution of birds responding to a group-selection timber harvest. Wildlife Society Bulletin, 36/2: 313-327.

Clark, J., J. Leung. 2011. Vocal distinctiveness and information coding in a suboscine with multiple song types: Eastern wood-pewee. The Wilson Journal of Ornithology, 123/4: 835-840.

Holoubek, N., W. Jensen. 2015. Avian occupancy varies with habitat structure in oak savanna of the south-central United States. The Journal of Wildlife Management, 79/3: 458-468.

Johnston, D. 1971. Niche relationships among some deciduous forest flycatchers. The Auk, 88/4: 796-804.

Kendrick, S., F. Thompson III, J. Reidy. 2014. Feeding rates, double brooding, nest rescue, and seasonal fecundity of eastern wood-pewees in the Missouri Ozarks. The Wilson Journal of Ornithology, 126/1: 128-133.

Kress, S., E. Wolfson. 2017. American Museum of Natural History: Pocket Birds of North America, Eastern Region. New York: DK Publishing.

Lederer, R. 1975. Bill size, food size, and jaw forces of insectivorous birds. The Auk, 92/2: 385-387.

McCarty, J. 1996. "Eastern wood-pewee (Contopus virens), The Birds of North America (P. G. Rodewald, Ed.)" (On-line). Ithaca, New York: Cornell Lab of Ornithology; Retrieved from the Birds of North America. Accessed September 10, 2017 at https://birdsna-org.lib-proxy.radford.edu/Species-Account/bna/species/eawpew/introduction.

Newell, F., A. Haiman, D. Narango, J. Elder, L. Leonhard, J. Philhower-Gillen, A. Johnson, A. Rodewald. 2013. Occurrence of polygyny and double brooding in the eastern wood-pewee. The Wilson Journal of Ornithology, 125/2: 251-259.

Newell, F., A. Rodewald. 2012. Management for oak regeneration: Short-term effects on the bird community and suitability of shelterwood harvests for canopy songbirds. The Journal of Wildlife Management, 76/4: 683-693.

Ridgely, R., J. Gwynne. 1989. A Guide to the Birds of Panama: With Costa Rica, Nicaragua, and Honduras. Princeton, New Jersey: Princeton University Press.

Rising, J., F. Schueler. 1980. Identification and status of wood pewees (Contopus) from the Great Plains: What are sibling species?. The Condor, 82: 301-306.

Sauer, J., W. Link, J. Fallon, K. Pardieck, D. Ziolkowski Jr.. 2013. The North American Breeding Bird Survey 1966-2011: Summary analysis and species accounts. North American Fauna, 79: 1-32.

Smith, J. 1988. Patterened daytime singing of the eastern wood-pewee, Contopus virens. Animal Behavior, 36: 1111-1123.

Underwood, T., S. Sealy, C. McLaren. 2004. Eastern wood-pewees as brown-headed cowbird hosts: Acceptors but infrequently parasitized. Journal of Field Ornithology, 75/2: 165-171.