Sayornis phoebeeastern phoebe

Geographic Range

Eastern phoebes (Sayornis phoebe) are found throughout much of North American during their breeding season. In Canada, their range extends as far north as the southern Northwest Territories, as far west as northeastern British Columbia, as far east as central New Brunswick, and southward to the United States. In the United States, their western boundary is just east of the Rocky Mountains, as far south as central New Mexico and central Texas. Their range extends as far east as northern Georgia, and northward along the east coast to Canada.

During the winter, eastern phoebes are found in the southern United States, Cuba, and Mexico. In the United States, they overwinter from Virginia southward along the east coast to Florida and westward through the Gulf States into central Texas. They overwinter as far south as Oaxaca, Mexico. (DeGraaf and Rappole, 1995; Hausman, 1941)

Habitat

Eastern phoebes are commonly found at the borders of woodlands near sources of freshwater, such as ponds and streams. They frequently nest in naturally occurring rocky outcrops, riverbanks, and near the entrances of caves. Phoebes often build their nests in areas with human presence, such as cities, suburban neighborhoods, and farming communities where man-made structures and natural resources are plentiful. Man-made nest locations include building eaves, abandoned buildings, and the undersides of bridges. (DeGraaf and Rappole, 1995; Ehrlich, et al., 1988; Hausman, 1941; Newton, 1998; Weeks Jr., 2011)

Physical Description

Eastern phoebes vary in overall head to tail length from 17.8 cm to 19 cm. Adults weigh 17 to 21 g and have wingspans of 26 to 28 cm. Eastern phoebes exhibit cryptic coloration with dull, brownish-gray coloration on their backs and tails, and slightly darker coloration on their heads. Their breasts and underbellies range in color from grayish-white during most of the year to pale yellow in the winter. They have no identifying wing bars and lack eye rings. The only visible difference between sexes is that males are slightly larger. Eastern phoebes have dark, broad-based beaks. The top bill turns downward slightly to end in a small hook and the lower bill has rictal bristles near the base. Rictal bristles function similarly to vibrissae in mammals, which helps eastern phoebes detect objects near them and navigate their environment.

Eastern phoebe hatchlings are altricial, with only a small amount of grayish down and eyes that remain closed until 6 to 8 days after birth. Eastern phoebes weight an average of 1.65 g at birth. (Baughman, 2003; Conrad and Robertson, 1993a; Hausman, 1941; Peterson, 2010; Rappole, 1995; The Cornell Lab of Ornithology, 2011; Weeks Jr., 2011)

  • Sexual Dimorphism
  • sexes alike
  • male larger
  • Range mass
    17 to 21 g
    0.60 to 0.74 oz
  • Range length
    14 to 17 cm
    5.51 to 6.69 in
  • Range wingspan
    26 to 28 cm
    10.24 to 11.02 in
  • Average basal metabolic rate
    0.3449 W
    AnAge

Reproduction

Eastern phoebes are socially monogamous. Females select one male with which to form a mating pair bond. The pair bond lasts for the duration of at least one breeding season. However, eastern phoebes exhibit a high rate of mate fidelity, so pair bonds typically last multiple breeding seasons. Females usually return to nest sites that they used in previous years, and males arrive soon after females. Males exhibit mate-guarding behavior, following their mate closely throughout nest preparation. Mating typically occurs in the early morning, when males are producing their territorial songs. (Beheler, et al., 2003; Bruni and Foote, 2014; Conrad, et al., 1998; Weeks Jr., 2011)

The breeding season of eastern phoebes varies geographically. In the southern United States, eastern phoebes typically begin breeding from mid to late March, whereas those located in the northern United States and southern Canada begin breeding around mid to late April. The nest-building phase of the breeding season takes place immediately after pair bonds are established. Females lay their first clutch of eggs approximately 2 weeks after they finish preparing their nests. Clutch size ranges from 3 to 8 eggs, with an average of 5 eggs per clutch. After laying their eggs, females incubate them for approximately 16 days before they hatch. Upon hatching, eastern phoebes weigh an average of 1.65 g. Within 16 to 20 days after hatching, juveniles are fully fledged, but still return to their nest between practice flights. Fledglings leave the nest permanently after another 14 to 16 days. Mating pairs often produce a second clutch of eggs around 1 to 2 weeks after their first brood has become independent. Eastern phoebes reach sexual maturity when they are approximately 1 year old. (Bent, 1963; Hauber, 2002; Weeks Jr., 2011)

The breeding season of eastern phoebes varies depending on their location. In the southern United States, eastern phoebes typically begin breeding from mid to late March, whereas eastern phoebes located in the northern United States and southern Canada begin breeding around mid to late April. The nest-building phase of the breeding season takes place immediately after pair bonds are established. Females lay their first clutch of eggs approximately 2 weeks after they finish preparing their nests. Clutch size ranges from 3 to 8 eggs, with an average of 5 eggs per clutch. After laying their eggs, females incubate them for approximately 16 days before they hatch. Upon hatching, eastern phoebes weigh an average of 1.65 g. Within 16 to 20 days after hatching, juveniles are fully fledged, but still return to their nest between practice flights. Fledglings leave the nest permanently after another 14 to 16 days. Mating pairs often produce a second clutch of eggs around 1 to 2 weeks after their first brood has become independent. Eastern phoebes reach sexual maturity when they are approximately 1 year old. (Bent, 1963; Hauber, 2002; Weeks Jr., 2011)

  • Breeding interval
    Eastern phoebes lay two successive clutches of eggs during their breeding season. Females lay the second clutch of eggs approximately 14 days after individuals from the first brood have left the nest.
  • Breeding season
    Late March to early July
  • Range eggs per season
    6 to 16
  • Average eggs per season
    10
  • Average eggs per season
    5
    AnAge
  • Average time to hatching
    16 days
  • Average time to hatching
    16 days
    AnAge
  • Range fledging age
    16 to 20 days
  • Range time to independence
    30 to 36 days
  • Average age at sexual or reproductive maturity (female)
    1 years
  • Average age at sexual or reproductive maturity (male)
    1 years

Eastern phoebes show considerable parental investment in their offspring, beginning with the preparation of suitable nests. Eastern phoebes often reuse nests from year to year, which allows them to begin mating and laying broods of eggs sooner. When eastern phoebes must invest time in building a new nest, they have less time later in the breeding season to rear a second brood of young.

Newborn eastern phoebes are altricial, with their eyes closed and with sparse, greyish down feathers. Newborns are completely dependent on their parents for food and protection. Both parents participate in collecting food for their young and removing fecal waste from the nest. Parental care reaches its peak around 14 days after eggs hatch, immediately prior to hatchlings taking their first flights. (Conrad and Robertson, 1993b; Hauber, 2001; Weeks Jr., 2011)

Lifespan/Longevity

Eastern phoebes have an average lifespan of 3 to 4 years in the wild. However, it is possible for them to live much longer as the oldest age on record for a wild individual is10.3 years. Eastern phoebes are not typically kept in captivity, so there is limited information on lifespans in captivity. (Monaghan and Metcalfe, 2000; Weeks Jr., 2011)

  • Range lifespan
    Status: wild
    10.3 (high) years
  • Average lifespan
    Status: wild
    3 to 4 years
  • Average lifespan
    Status: wild
    3 to 4 years
  • Average lifespan
    Status: wild
    124 months
    Bird Banding Laboratory

Behavior

Eastern phoebes are mainly active during the day and roost at night. During breeding season, females roost in the nest with their young with males perch nearby. In preparation for breeding season, males migrate to the breeding range approximately 2 weeks prior to females. Once females arrive, they choose their mates and form pair bonds. Females then choose a nesting location, which is often a nest used during the previous breeding season. Phoebes frequently make nests in man-made structures, such as bridges and building eaves. Females construct nests using organic materials such as green moss, mud, leaves, grass, and hair. Females interact with males as needed for nest preparation, reproduction, and nestling care, but no more than necessary. Eastern phoebes are solitary outside of breeding season, foraging and roosting by themselves.

During the breeding season, male eastern phoebes spend several hours before dawn singing. They sing an alternation of two different songs, "phee-bee" and "phee-b-be-bee." The purpose of these songs is likely an indicator of male fitness and mate quality, and thus a method of attracting females. It has been observed that males begin singing earlier in the morning and for longer durations at the height of female fertility.

Eastern phoebes can be difficult to identify visually due to their lack of unique markings. However, they exhibit a unique "tail-pumping" behavior, which can be used to positively identify them. Phoebes pump their tails up and down while they are perched. This behavior is thought to be a predator deterrent, signaling to potential predators that they have been spotted and should not try attacking. (Bruni and Foote, 2014; Carder and Ritchison, 2009; Weeks Jr., 2011)

  • Average territory size
    3 m^2

Home Range

Eastern phoebes are territorial over their nest sites. They do not leave the immediate area when foraging for food sources. During the breeding season, eastern phoebes do not venture farther than 100 m from their nests. (Weeks Jr., 2011)

Communication and Perception

Eastern phoebes are born with an innate ability to sing an alternating song of "phoebe," pronounced "fe-bee." Juveniles are able to sing without auditory learning, meaning they do not need to hear other phoebes singing in order to learn the song. Both males and females have been observed using this song for communication.

Eastern phoebe males use singing as a method of mate attraction. Males typically increase their time spent vocalizing during the breeding season when females are the most fertile and during incubation periods. Increased male vocalization alerts females to the qualities of mate suitability and strength.

Eastern phoebes use tail-pumping as a predator-deterrent. They have been observed pumping their tails persistently when predators are within close proximity. This visual cue, along with repetitive vocal calls, signals to a potential predator that the individual eastern phoebe has spotted them and that it will be difficult to catch.

Visual acuity is necessary for eastern phoebes to hunt. They catch most of their insect prey through aerial hawking, or otherwise by "sallying", a technique that involves swooping down from a perch towards the ground to capture prey. Both of these techniques require strong eyesight to initially detect prey. (Baughman, 2003; Bruni and Foote, 2014; Carder and Ritchison, 2009; Hausman, 1941; Kroodsma, 1985; Kroodsma and Konishi, 1991; Peterson, 2010; Rappole, 1995; Troy and Baccus, 2009; Weeks Jr., 2011)

Food Habits

Eastern phoebes are part of the family Tyrannidae, aptly called "tyrant flycatchers", as their main food choices are flying insects from the order Hymenoptera, which includes bees, wasps, and sawflies. Being insectivores, they also feed on species in the orders Coleoptera (beetles), Orthoptera (grasshoppers, crickets, katydids, and locusts), Hemiptera (true bugs, cicadas, aphids, and leafhoppers), Lepidoptera (moths and butterflies), Diptera (flies), and non-insect arthropods such as millipedes (subphylum Myriapoda) and spiders and ticks (class Arachnida). During the fall, winter, and spring, when insect availability is limited, eastern phoebes also eat seeds, berries, mollusks, amphibians, and even small fish. The bristles at the base of their bills are thought to aid in recognition of captured prey. (Baughman, 2003; Bent, 1963; Ehrlich, et al., 1988; Peterson, 2010; Weeks Jr., 2011)

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

Predation

Eastern phoebes serve as prey for birds, mammals, and snakes. Known and suspected predators of adult phoebes include northern saw-whet owls (Aegolium acadicus), merlins (Falco columbarius), and sharp-shinned hawks (Accipiter striatus).

Brooding females are at an increased risk of predation, as are eggs and nestlings. Common nest predators include blue jays (Cyanocitta cristata), American crows (Corvus brachyrhynchos), house wrens (Troglodytes aedon), raccoons (Procyon lotor), coyotes (Canis latrans), eastern chipmunks (Tamias striatus), white-footed mice (Peromyscus leucopus), and black rat snakes (Pantherophis alleghaniensis).

Eastern phoebes have brownish-gray coloration that helps them blend into their surroundings. They also use tail-pumping motions and "chip" warning calls to alert potential predators that they have been spotted. If protecting nestlings, eastern phoebes will directly attack potential predators by flying at them. (Bent, 1963; Carder and Ritchison, 2009; Rappole, 1995; Weeks Jr., 2011)

  • Anti-predator Adaptations
  • cryptic

Ecosystem Roles

Eastern phoebe nests are often parasitized by brown-headed cowbirds (Molothrus ater). Cowbirds will lay their own eggs into the nests of other birds, such as eastern phoebes. Female then raise brown-headed cowbird hatchlings along with their own offspring. This behavior can have negative consequences for newborn eastern phoebes, since hatchlings in nests with brood parasites receive less parental care.

Eastern phoebes serve as hosts for several types of mites, including wild bird mites (Liponyssus sylviarum), feather mites (Pterodectes banksi), and northern fowl mites (Ornithonyssus sylviarum). These mites generally do not cause extreme harm to adults, but they can be spread to juveniles that are more vulnerable. The larvae of avian blowflies (Protocalliphora deceptor) often parasitize phoebe hatchlings, but typically do not increase mortality rates. Conversely, parasitization by ticks such as Carios concanensis has been reported to result in mortality in juvenile eastern phoebes. (Hauber, 2001; Hauber, 2003; Wagner, et al., 2013; Weeks Jr., 2011)

Commensal/Parasitic Species

Economic Importance for Humans: Positive

Eastern phoebes have been the subjects of extensive research in bird reproduction, nesting practices, and brood parasitism. They have been beneficial research subjects because of their tendency to live and roost near human development. (Weeks Jr., 2011)

  • Positive Impacts
  • research and education

Economic Importance for Humans: Negative

There are no known adverse effects of eastern phoebes on humans.

Conservation Status

Eastern phoebes are classified as a species of "least concern" on the IUCN Red list. It is reported that their populations are increasing in size. They are classified as "protected" under the Migratory Bird Treaty Act, which means it is illegal to own eastern phoebe adults, juveniles, eggs, or nests. Furthermore, it is a criminal offense to attempt to profit from the possession of eastern phoebes.

Eastern phoebes commonly build nests in areas populated by humans, which has resulted in a dependency on man-made structures. When these structures are destroyed or altered, phoebes must rebuild or relocate their nests. Humans are often responsible for destroying nests out of concern that they will catch disease from bird droppings.

Eastern phoebes are susceptible to changes made in the man-made structures they use for nesting. Problems occur when updated materials, such as corrugated metal or plastic pipes, are used in bridge construction. Eastern phoebes are either unable to access these types of pipes, or the surfaces do not provide a stable platform on which to build new nests. Conservation efforts for eastern phoebes include programs to build alternative nesting platforms. These platforms are placed within concrete culverts and have shown to be successful alternative nesting locations.

Phoebes have no special status in the CITES appendices or any other international or national conservation list. (BirdLife International, 2012; Weeks Jr., 2011)

Contributors

Holly Rindorf (author), Radford University, Karen Powers (editor), Radford University, April Tingle (editor), Radford University, Emily Clark (editor), Radford University, Cari Mcgregor (editor), Radford University, Jacob Vaught (editor), Radford University, Galen Burrell (editor), Special Projects.

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

agricultural

living in landscapes dominated by human agriculture.

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.

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

cryptic

having markings, coloration, shapes, or other features that cause an animal to be camouflaged in its natural environment; being difficult to see or otherwise detect.

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

frugivore

an animal that mainly eats fruit

granivore

an animal that mainly eats seeds

herbivore

An animal that eats mainly plants or parts of plants.

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).

male parental care

parental care is carried out by males

migratory

makes seasonal movements between breeding and wintering grounds

molluscivore

eats mollusks, members of Phylum Mollusca

monogamous

Having one mate at a time.

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.

piscivore

an animal that mainly eats fish

riparian

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

sexual

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

solitary

lives alone

suburban

living in residential areas on the outskirts of large cities or towns.

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).

terrestrial

Living on the ground.

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

tropical

the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.

urban

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

visual

uses sight to communicate

References

Baughman, M. 2003. National Geographic Reference Atlas to the Birds of North America. Washington, D.C.: National Geographic Society.

Beheler, A., O. Rhodes, H. Weeks, F. Moore. 2003. Breeding site and mate fidelity in eastern phoebes (Sayornis phoebe) in Indiana. The Auk, 120/4: 990-999.

Bent, A. 1963. Life Histories of North American Flycatchers, Larks, Swallows, and Their Allies. London: Constable and Company, Limited.

BirdLife International, 2012. "Sayornis phoebe" (On-line). The IUCN Red List of Threatened Species. Version 2014.3. Accessed March 23, 2015 at www.iucnredlist.org.

Bruni, A., J. Foote. 2014. Dawn singing of eastern phoebes varies with breeding stage and brood number. The Wilson Journal of Ornithology, 126/3: 500-507.

Carder, M., G. Ritchison. 2009. Tail pumping by eastern phoebes: An honest, persistent predator-deterrent signal?. Journal of Field Ornithology, 80/2: 163-170.

Conrad, K., R. Robertson. 1993. Patterns of parental provisioning by eastern phoebes. Condor, 95/1: 57-62.

Conrad, K., R. Robertson. 1993. Relationship of age and sex to size and color of eastern phoebes. The Wilson Bulletin, 105/4: 597-603.

Conrad, K., R. Robertson, P. Boag. 1998. Frequency of extrapair young increases in second broods of eastern phoebes. The Auk, 115/2: 497-502.

DeGraaf, R., J. Rappole. 1995. Neotropical Migratory Birds: Natural History, Distribution, and Population Change. Ithaca, NY: Cornell University Press.

Eastman, J. 1997. Birds of Forest, Yard, and Thicket. Mechanicsburg, Pa: Stackpole Books.

Ehrlich, P., D. David, W. Darryl. 1988. The Birder's Handbook: A Field Guide to the Natural History of North American Birds. New York, NY: Simon & Schuster.

Hauber, M. 2003. Hatching asynchrony, nestling competition, and the cost of interspecific brood parasitism. Behavioral Ecology, 14/2: 227-235.

Hauber, M. 2002. Is reduced clutch size a cost of parental care in eastern phoebes (Sayornis phoebe)?. Behavioral Ecology and Sociobiology, 51/6: 503-509.

Hauber, M. 2001. Site selection and repeatability in brown-headed cowbird (Molothrus ater) parasitism of eastern phoebe (Sayornis phoebe) nests. Canadian Journal of Zoology, 79/8: 1518-1524.

Hausman, L. 1941. Field Book of Eastern Birds. New York, NY: G. P. Putnam's Sons.

Kroodsma, D. 1985. Development and use of two song forms by the eastern phoebe. The Wilson Bulletin, 97/1: 21-29.

Kroodsma, D., M. Konishi. 1991. A suboscine bird (eastern phoebe, Sayornis phoebe) develops normal song without auditory feedback. Animal Behavior, 42/3: 477-488.

Monaghan and Metcalfe, 2000. Genome size and longevity. Trends Genet, 16/8: 331-332.

Newton, I. 1998. Population Limitation in Birds. San Diego, CA: Academic Press Inc.

Peterson, R. 2010. Peterson Field Guide to Birds of Eastern and Central North America. New York, NY: Houghton Mifflin Harcourt Publishing Company.

Rappole, J. 1995. The Ecology of Migrant Birds: A Neotropical Perspective. Front Royal, VA: Smithsonian Institution.

The Cornell Lab of Ornithology, 2011. "Eastern Phoebe, Life History, All About Birds" (On-line). Accessed April 10, 2015 at http://www.allaboutbirds.org/guide/Eastern_Phoebe/lifehistory.

Troy, J., J. Baccus. 2009. Effects of weather and habitat on foraging behavior of non-breeding eastern phoebes. Wilson Journal of Ornithology, 121/1: 97-103.

Wagner, G., Z. Aidala, R. Croston, M. Hauber. 2013. Repeated brood parasitism by brown-headed cowbirds (Molothrus ater) at nesting sites of eastern phoebes (Sayornis phoebe) across non-consecutive years. The Wilson Journal of Ornithology, 125/2: 389-394.

Weeks Jr., H. 2011. Eastern Phoebe (Sayornis phoebe), The Birds of North America Online (A. Poole, Ed.). Ithaca, NY: Cornell Lab of Ornithology. Accessed February 26, 2015 at Cornell Lab of Ornithology.