Commonly known as American redstarts, (Sherry and Holmes, 1997)is a Neotropical migrant warbler that spends portions of the year in both the Nearctic and the Neotropical regions. During the spring and summer, breeds across much of Canada and the United States. It inhabits the southern regions of Canada from the east to west coast. In the United States, may be found in limited regions of the northern Midwest, and most states east of the Mississippi River. Exclusions include portions of Kentucky, Tennessee, Florida, Georgia, and North and South Carolina. This species migrates biannually across much of the United States and Central America to reach its wintering grounds in southern Central and northwestern South America. also overwinters on many Caribbean islands including Jamaica and Cuba.
selects varying habitats depending on the season and geographic location. During the breeding season, this warbler inhabits open-canopy, mostly deciduous forests, second growth, and forest edge across much of the United States and southern Canada. This insectivorous bird often shares its foraging habitats with other warblers, and is found feeding in the mid to lower regions of a tree or shrub. prefers to build its nest well within dense shrubs or the fork of a low tree, and males will select territories that contain several of these potential nest sites.
One study has demonstrated a correlation between male coloration and level of parental investment. Male (Germain, et al., 2010)that featured brighter orange coloration on the flanks made significantly more trips to the nest and overall spent more time at the nest. Therefore, male flank coloration may play a role in sexual selection and may explain why first-year males have low levels of reproductive success until they obtain their adult, black and orange coloration.
The oldest (Sherry and Holmes, 1997)on record was a male banded in adult plumage (making it at least 2 years old) which was re-captured approximately 9 years later, making it at least 10 years old. There is evidence that many females live to be at least 5. is not kept in captivity and thus there is no data for captive lifespan. Annual survival rates are estimated to be between 50 and 60%. Females are thought to suffer a slightly higher mortality rate as they spend significantly more time on the nest (brooding) and are often consumed by nest predators.
primarily uses vocal and visual forms of communication. Male give distinctive songs which are used to defend territory or attract mates. Songs of this species are highly variable but are generally rapid and high pitched. Songs may repeat the same 1 or 2 phrases or have 2 to 8 different phrases given in rapid succession. Some songs end in an accented, terminal note while others simply end unaccented. uses these different song types to communicate in different situations. Repeated songs with accented endings are typically used for attracting mates, or while males are in close proximity to their mates. Unmated males usually use only this song type. After males secure a mate, they then switch to singing serial songs to defend their territories against neighboring birds. Like many birds, a significant amount of song variation is due to local dialects. Many individuals can be identified by distinct characteristics of their song such as pattern, frequency, or distinctive syllables. Males of this species can quickly learn the songs of neighboring rivals and incorporate them into their own songs, leading to unique neighborhood dialects.
also uses body postures and movements as communication. During courtship, males will often chase potential mates in a somewhat aggressive manner and interested females will respond by flying a short distance, then giving a tail-spreading display. Males often give two types of displays towards females: fluff displays and bows. Fluff displays consist of fluffing the body feathers, particularly the bright orange flanks. There is evidence that brighter orange flanks correlate to higher levels of male parental investment, and raising these feathers may serve to advertise parental quality. Bow displays are typically given later in courtship, when a male sleeks his feathers, lowers his breast to the ground, and holds his head vertically.
This species is highly territorial year-round and employs song, body postures, and aerial attacks to deter intruders. As discussed above, males often advertise territory boundaries through singing, but females also give a variety of chips and short notes towards intruders. Both males and females assume threatening body postures including head-forward displays with drooping wings and bill agape, and tail-spreading displays with tail held near vertically. Males also give a wings-out display where they raise and spread their wings, likely to display the orange wing patches. Males also make distinctive circling flights during territorial disputes. Two neighboring males (occasionally females) will alternate short, deliberate, circling flights in pursuit of each other.
Muscicapidae and Tyrannidae, respectively) and thus these species share similar foraging behaviors and diets. employs the foliage gleaning method to capture prey and often flicks its brightly-patterned tail to flush stationary prey. Flying prey is then pursued and caught aerially, after which the bird lands on a different perch than it alighted from. is known for highly energetic foraging habits and is often seen rapidly hopping through all heights of vegetation. It prefers to forage from twigs and branches versus tree trunks or limbs. Overall, this species is a very flexible, opportunistic feeder that can easily adapt to varying habitat, season, insect community, vegetation structure, and time of day. Diet consists largely of caterpillars, moths, flies, leafhoppers and planthoppers, small wasps, beetles, aphids, stoneflies, and spiders. Few berries and seeds are consumed, but are most often from barberry (Berberis), serviceberry (Amelanchier), and magnolia (Magnolia). (Ehrlich, et al., 1988; Sherry and Holmes, 1997)is nearly exclusively insectivorous, but will occasionally consume berries or seeds during the fall when insect abundance decreases. Morphologically, the flattened beak and rictal bristles are similar to old and new world flycatchers (
red squirrels, fishers, eastern chipmunks, black bears, flying squirrels, fox snakes, and domestic cats. Aerial predators take nestlings, eggs, or even adults in flight. Possible aerial predators include jaegers, blue jays, common ravens, northern saw-whet owls, common grackles, northern goshawks, and sharp-shinned hawks, and Cooper's hawks. (McCallum and Hannon, 2001; Sherry and Holmes, 1997)is vulnerable to both terrestrial and aerial predators. Highest rates of predation occur during the breeding season when eggs and helpless nestlings are abundant and easy prey for terrestrial predators. Females mostly brood during this period and thus often fall prey to nest predators. Common terrestrial predators include
As an insectivore, brown-headed cowbirds and currently will accept and successfully raise cowbird chicks. Populations of that are exposed to Molothrus ater will react more aggressively to adults than populations that have encountered them less often. (Ehrlich, et al., 1988; Sherry and Holmes, 1997)consumes significant amounts of insects and likely has an impact on local insect communities. This species also consumes small amounts of fruits and seeds during the fall which may contribute to seed distribution for the plant species it feeds upon. Eggs, nestlings, and adults are consumed by a wide variety of predators. Like many birds, this species is host to several ectoparasites including three lice species and one tick. is a common host for
There are no known adverse effects ofon humans.
brown-headed cowbirds which decrease reproductive success. Currently, there are few conservation efforts being made for this species, as it is still of least concern. In general, efforts are being made to create sustainable logging practices that support the creation of early-successional habitat. Sustainable farming practices, such as shade-grown coffee, are becoming more prevalent on Central and South American countries that strike a balance between agriculture and providing habitat for songbirds. Many local Audubon chapters are promoting "lights out" campaigns that work with businesses to turn lights off in large skyscrapers during peak migration season, which reduces migrating bird collisions and fatalities. (Sherry and Holmes, 1997)is listed as least concern by the International Union for Conservation of Nature and Natural Resources (IUCN) an account of its wide geographic range and relatively stable population size. Recent population data however, has shown this species to be in slight decline and numbers should be monitored closely in the future. Like many declining Neotropical migrants, this species likely suffers from habitat loss on both the wintering and breeding grounds. The main causes for habitat loss is logging for human conversion of land to urban or residential areas. also prefers shrubby, early-successional habitats which naturally age and progress to mature forests which are less suitable. This species also suffers significant fatalities from impacts with man-made structures during night migration. Over four fall migrations, two towers in Florida accounted for over 1,600 deaths. is also a common host for
Rachelle Sterling (author), Special Projects, Tanya Dewey (editor), University of Michigan-Ann Arbor, George Hammond (editor), Animal Diversity Web Staff, Tricia Jones (editor), University of Michigan-Ann Arbor, ADW Zookeeper (editor), University of Michigan-Ann Arbor.
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.
living in the southern part of the New World. In other words, Central and South America.
uses sound to communicate
living in landscapes dominated by human agriculture.
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.
Referring to an animal that lives in trees; tree-climbing.
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.
an animal that mainly eats meat
uses smells or other chemicals to communicate
ranking system or pecking order among members of a long-term social group, where dominance status affects access to resources or mates
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.
parental care is carried out by females
forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.
An animal that eats mainly insects or spiders.
referring to animal species that have been transported to and established populations in regions outside of their natural range, usually through human action.
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).
parental care is carried out by males
makes seasonal movements between breeding and wintering grounds
Having one mate at a time.
having the capacity to move from one place to another.
reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.
scrub forests develop in areas that experience dry seasons.
breeding is confined to a particular season
reproduction that includes combining the genetic contribution of two individuals, a male and a female
uses touch to communicate
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).
Living on the ground.
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
the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.
uses sight to communicate
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Ehrlich, P., D. Dobkin, D. Wheye. 1988. The Birder's Handbook: A Field Guide to the Natural History of North American Birds. New York, NY: Simon and Schuster.
Ficken, M. 1962. Agonistic behavior and territory in the American Redstart. The Auk, 79: 607-632.
Ficken, M. 1963. Courtship of the American Redstart. The Auk, 80: 307-317.
Germain, R., M. Reudink, P. Marra, L. Ratcliffe. 2010. Carotenoid-based Male Plumage Predicts Parental Investment in the American Redstart. The Wilson Journal of Ornithology, 122/2: 318-325.
Marra, P., R. Holmes. 2001. Consequences of dominance-mediated habitat segregation in American redstarts during the nonbreeding season. The Auk, 118/1: 92-104.
McCallum, C., S. Hannon. 2001. Accipiter predation of American redstart nestlings. The Condor, 103/1: 192-194.
Sherry, T., R. Holmes. 1997. "American Redstart (Setophaga ruticilla)" (On-line). The Birds of North America Online. Accessed June 13, 2011 at http://bna.birds.cornell.edu/bna/species/277.
Sibley, D. 2000. The Sibley's Guide to Birds. New York: Alfred A. Knopf, Inc.