Contopus sordidulus

Geographic Range

Contopus sordidulus are found in western North America, starting in east central Alaska, to northwestern Minnesota, all the way south into southern Baja. In the fall they leave the northern area and head towards the south. During the winter, they can be found migrating even further south to Panama.

• Biogeographic Regions
• nearctic nearctic
• neotropical neotropical

Habitat

In the summer, C. sordidulus are found in evergreen forests, woodlands, coniferous forests, and also open and closed canopy forests. In the winter they can also be found in agricultural fields, meadows, grasslands, and thickets. In general, western wood-pewees prefer dry environments.

Western wood-pewees are seen close to land but are usually found in tall treetops. They build nests at the end of tree branches. The limbs can either be dead or alive, the birds have no known preference. Usually the branches are at least 5-12 meters above the ground. The nests are weaved out of fiber, grasses, lichens, spider webs, and shredded bark and are shaped like shallow cups. The blending of the color and the shape to the tree allows them to go practically unnoticed resembling stubs on the branches.

• Habitat Regions
• temperate temperate

• Terrestrial Biomes
• forest forest

• Aquatic Biomes
• rivers and streams

• Other Habitat Features
• riparian riparian

Physical Description

Tail: 7-7.62 cm

Western wood-pewees have angular heads with moderate crests. Their flanks and sides are dark brown with blurry streaks that go toward the lower sides. Their tertials are distinctly fringed and are more obvious than their wing bars. Western wood-pewees' tails are short relative to their body proportions. They have long upper tail coverts which reach the midway point of the primary extensions, which are known to be long. Their bills are mostly dark, the lower mandibles are about 50% darker than the unpper mandibles. Their breasts have an olive look. Also, the throats have a whitish color which continues on their bellies and under their tails.

There are differences between the adult and the juvenile plumage. The adult has more of a grayish throat whereas the juvenile has a dull color. Also the wing bars are not as vibrant on juveniles as they are on adult C. sordidulus .

• Other Physical Features
• endothermic endothermic
• homoiothermic
• bilateral symmetry bilateral symmetry

• Sexual Dimorphism
• sexes alike

Reproduction

Mating begins in early May but the prime time is around June. The male sings to defend a nesting territory and also uses the songs to attract a mate. The male then takes over a woodland territory that is about 2-6 acres. They are seasonally monogamous.

• Mating System
• monogamous monogamous

The female usually lays 2-4 eggs. When the young are born, the incubation time lasts for about 12 days. By the 7th day, the young have developed all their feathers. The fledging process lasts about 14-18 days and then they leave the nest within the 3 days of fledging.

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

The young are tended by both parents, but the female is usually at the nest the most during the first 4 days. The young are fed insects.

• Parental Investment
• altricial altricial
• pre-weaning/fledging
  • provisioning
  • protecting
    • male
    • female

Lifespan/Longevity

Although information on the exact life expectancy of C. sordidulus is unavailable, eastern wood-pewees , which are very similar to western wood-pewee groups, have a life expectancy of about 7 years.

Behavior

Contopus sordidulus appear calm. They perch on the branches for a long amount of time, usually to watch for prey. They fly occasionaly to catch insects that are in the air.

• Key Behaviors
• arboreal arboreal
• flies
• diurnal diurnal
• motile motile
• migratory migratory

Home Range

Home range information could not be found for this species.

Communication and Perception

Contopus sordidulus are very hard to differentiate from other birds in their family, such as eastern wood-pewees . But the one thing that does stand out is their communication calls. Eastern wood-pewees have a nasal whistle that sounds like "DREE-yurr" or "breerrr". It sounds very rough. Western wood-pewees sound a bit different, like a plain, sneezy, "brrrt". During breeding a sound is sent out as "tswee-tee-teet".

• Communication Channels
• acoustic acoustic

• Perception Channels
• visual visual
• tactile tactile
• acoustic acoustic
• chemical chemical

Food Habits

The majority of the time, C. sordidulus feed on insects such as flies , wasps , bees , ants , beetles , moths , and butterflies . On other occasions they eat dragonflies , termites , and spiders . All the insects are caught in the air. Contopus sordidulus hunt from the perch and capture prey by twisting very quickly in the air. Immediately after catching a prey item, they return to the perch.

• Primary Diet
• carnivore carnivore
  • insectivore insectivore
  • eats non-insect arthropods

• Animal Foods
• insects
• terrestrial non-insect arthropods

Predation

Blue jays are nest predators on this species. They will feed on the young in the nest. Hawks are also predators of C. sordidulus . The nest is made up of colors that will allow it to look like a stump on the tree. Camouflage is their way of avoiding predation.

• Anti-predator Adaptations
• cryptic cryptic

Ecosystem Roles

Contopus sordidulus provide food for blue jays as well as other predators. Western wood-pewees also prey on various insects and spiders.

Economic Importance for Humans: Positive

Songbirds such as western wood-pewees, are important to birdwatchers. In addition, as generalist insectivores, they may affect pest populations.

• Positive Impacts
• ecotourism ecotourism
• controls pest population

Economic Importance for Humans: Negative

Western wood-pewees have no known negative affects on humans.

Conservation Status

Contopus sordidulus are abundant, but according to the Breeding Bird Survey, there is an increase in Washington but a decrease in British Colombia and Oregon. The decrease could be due to the loss of habitat on breeding grounds and winter grounds.

Other Comments

If people disturb the birds then there is a possibility that the mother will leave her nest. This is usually caused by an overabundance of human activity surrounding them. The mothers would not only leave the nest, but her young as well.

Additional Links

Encyclopedia of Life

Contributors

Matthew Wund (editor), University of Michigan-Ann Arbor.

Lynn Gasparella (author), University of Michigan-Ann Arbor, Phil Myers (editor), Museum of Zoology, University of Michigan-Ann Arbor.

References

Coves, E. 1890. Key to North American Birds . Boston: Estes and Lauriat.

DeGraaf, R., J. Rappole. 1995. Neotropical Migratory Birds Natural History, Distribution, and Population Change . New York: Comstock Publishing Associates.

Eastman, J. 1997. Birds of Forest, Yard, & Thicket . Pennsylvania: Stackpole Books.

Harrison, C. 1978. A Field Guide to the Nests, Eggs, and Nestlings of North American Birds . Glasgow, United Kingdom: William Collins Sons & Co Ltd.

National Geographic, 1999. Field Guide to the Birds of North America . Washington DC: National Geographic.

Phillips, A., J. Marshall, G. Monson. 1964. The Birds of Arizona . Arizona: University of Arizona Press.

Price, J., S. Droege, A. Price. 1995. The Summer Atlas of American Birds . California: Harcourt Brace & Company.

Shuford, D. 1993. The Marin County Breeding Bird Atlas . California: Bushtit Books.

Sibley, D. 2000. The North American Bird Guide . United Kingdom: Pica Press.

Small, A. 1994. California Birds Their Status and Distribution . California: IBIS Publishing Company.

USGS, 2003. "Western wood-pewee Contopus sordidulus Identification Tips" (On-line ). Accessed 03/19/03 at http://www.mbr-pwrc.usgs.gov/id/framlst/account/h4620id.html .

USGS, 2003. "Western wood-pewee Contopus sordidulus Life History Groupings" (On-line ). Accessed 03/19/03 at http://www.mbr-pwrc.usgs.gov/id/framlst/button/lh4620.html .

2002. "Seattle Audubon Society" (On-line ). Western wood-pewee. Accessed 04/09/03 at http://www.birdweb.org/birdweb/species.asp?id=282 .

Darryl Wheye. 1999. "Western Wood Pewee" (On-line). Accessed April 09, 2003 at http://www.stanfordalumni.org/birdsite/ .