Gray Flycatcher
Encyclopedia
The American Gray Flycatcher, or just Gray Flycatcher, (Empidonax wrightii) is a small, insectivorous passerine
in the tyrant flycatcher
family
. It is common in the arid
region
s of western North America
, especially the Great Basin
. From sagebrush
steppes
to pinyon
-juniper
woodland
s and ponderosa pine
forest
s, this flycatcher forages
for insect
s from shrub
s or low tree
branches.
The Gray Flycatcher is one of many species
in the genus
Empidonax
. These species are very similar in appearance and behavior
, and they are notoriously difficult to differentiate. The best characteristics for distinguishing these species are voice
, breeding habitat
, and range
. The Gray Flycatcher, however, can be identified by a unique behavior
, its downward tail wag. Other Empidonax species typically exhibit a rapid upward tail flick.
s, but larger than most Empidonax flycatchers. A typical adult measures 15 cm (6 in) in length, 22 cm (9 in) in wingspan
, and 12.5 g (0.44 oz) in mass
.
Adults have pale gray upperparts, darker on the wing
s and tail
, with a faint olive tinge after molting in fall. Underparts are whitish, but washed slightly with yellow in fresh plumage
. They have white wing bars and an inconspicuous white eye ring. There is a pale supraloral band stretching above the base of the bill
. Relative to other North American Empidonax flycatchers, the Gray Flycatcher has a long, narrow bill, a long tail, and the mandible
tends to be paler for more of its length.
Juveniles
are similar in appearance to adults, but with stronger olive and yellow tones. Also, young birds have buffy wing bars and brownish breasts.
Only the male sings. The song is a strong, two syllable note described as chuwip or wilip. A weaker, higher-pitched teeap or seep is often inserted into the song. Both sexes give a dry pit or wit call. Females call often when foraging
or collecting nest materials.
to the American Dusky Flycatcher (Empidonax oberholseri), which has been problematic in taxonomy
. When described as a species in 1889, the Gray Flycatcher was named Empidonax griseus. This name was reduced to synonymy
when it was discovered that the type
specimen
designated for the Dusky Flycatcher was in fact a Gray Flycatcher. The name then in use for Dusky Flycatcher was Wright’s flycatcher (E. wrightii), a name proposed in 1858. Because the name wrightii took precedence, it was applied to the Gray Flycatcher, leaving the Dusky Flycatcher to be given a new name, E. oberholseri.
There are no recognized subspecies
, and there is no geographic variation reported.
The International Ornithological Congress uses the name American Grey Flycatcher for Empidonax wrightii to differentiate it from the African Grey Flycatcher and the Ethiopian Grey Flycatcher. However, the American Ornithologists' Union (which covers North and Middle America) names it Gray Flycatcher.
through a narrow zone in central Washington to eastern Oregon
and California
. The range extends east across Nevada
, southern Idaho
, Utah
, and northern Arizona
to southwestern Wyoming
, western Colorado
, and northwestern New Mexico
.
Depending on latitude
, they arrive on breeding grounds mid-April to mid-May and leave between mid-August and mid-September. Migration
between breeding and wintering grounds takes approximately seven weeks in both spring and autumn. Males usually arrive on breeding grounds one week prior to arrival of females.
The Gray Flycatcher winters in Baja California Sur
, southeastern Arizona, and central Sonora
to central Oaxaca
. Small numbers may winter in western Texas
and southern California.
, open woodland, or forest with bare understory
. Although it is typically dominated by sagebrush (Artemisia
spp), common associations include bitterbrush (Purshia
spp), rabbitbrush (Chrysothamnus
spp, Ericameria
nauseosus), mountain-mahogany (Cercocarpus ledifolius), juniper (Juniperus spp.), pinyon pine (Pinus spp.), and ponderosa pine (Pinus ponderosa).
During migration habitat is generally similar to breeding habitat, but riparian areas are often used. Thus, migrants may be found in willow (Salix spp.), oaks (Quercus spp.), or mesquite (Prosopis
spp.).
In winter the Gray Flycatcher is found in "arid open and semiopen areas with scrub and scattered trees".
Most prey is taken in flight
or from the ground. A bird will wait on an open perch – usually on a shrub or low tree branch – and fly out to catch a passing insect. Less commonly, a hovering bird gleans
prey from foliage or bark
.
during the breeding season. Males establish a territory and attract a female through vocalizations and displays. They appear to be monogamous, but extra-pair copulations may occur.
The nest
is bulky and less compact than those of other Empidonax flycatchers. The female builds the nest (males rarely help) from various plant materials, especially grass stalks and strips of bark. The nest is usually lined with softer materials, such as wool, hair, feathers, or soft grasses. Nests may be placed in sagebrush, bitterbrush, junipers, or pines. Nest height depends in part on the height of the substrate (i. e., nests tend to be higher in taller trees) but is usually 1–6 m (3–20 ft) above ground. Most nests are placed in the crotch of a branch next to the trunk, but some are situated on larger branches away from the trunk.
Females lay one egg
per day, with a final clutch size
of three or four. The female incubates
the eggs for about two weeks. The eggs, although laid on different days, usually hatch on the same day. The chicks are altricial
and have little down when they hatch. Both parents feed the nestlings. Fledging
occurs about 16 days after hatching.
Passerine
A passerine is a bird of the order Passeriformes, which includes more than half of all bird species. Sometimes known as perching birds or, less accurately, as songbirds, the passerines form one of the most diverse terrestrial vertebrate orders: with over 5,000 identified species, it has roughly...
in the tyrant flycatcher
Tyrant flycatcher
The tyrant flycatchers are a family of passerine birds which occur throughout North and South America. They are considered the largest family of birds on Earth, with more than 400 species. They are the most diverse avian family in every country in the Americas, except for the United States and...
family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
. It is common in the arid
Arid
A region is said to be arid when it is characterized by a severe lack of available water, to the extent of hindering or even preventing the growth and development of plant and animal life...
region
Region
Region is most commonly found as a term used in terrestrial and astrophysics sciences also an area, notably among the different sub-disciplines of geography, studied by regional geographers. Regions consist of subregions that contain clusters of like areas that are distinctive by their uniformity...
s of western North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
, especially the Great Basin
Great Basin
The Great Basin is the largest area of contiguous endorheic watersheds in North America and is noted for its arid conditions and Basin and Range topography that varies from the North American low point at Badwater Basin to the highest point of the contiguous United States, less than away at the...
. From sagebrush
Sagebrush
Sagebrush is a common name of a number of shrubby plant species in the genus Artemisia native to western North America;Or, the sagebrush steppe ecoregion, having one or more kinds of sagebrush, bunchgrasses and others;...
steppes
Shrub-steppe
Shrub-steppe is a type of low rainfall natural grassland. Shrub-steppes are distinguishable from deserts, which are too dry to support a noticeable cover of perennial grasses or other shrubs, while the shrub-steppe has sufficient moisture levels to support a cover of perennial grasses and/or...
to pinyon
Pinyon pine
The pinyon pine group grows in the southwestern United States and in Mexico. The trees yield edible pinyon nuts, which were a staple of the Native Americans, and are still widely eaten...
-juniper
Juniper
Junipers are coniferous plants in the genus Juniperus of the cypress family Cupressaceae. Depending on taxonomic viewpoint, there are between 50-67 species of juniper, widely distributed throughout the northern hemisphere, from the Arctic, south to tropical Africa in the Old World, and to the...
woodland
Woodland
Ecologically, a woodland is a low-density forest forming open habitats with plenty of sunlight and limited shade. Woodlands may support an understory of shrubs and herbaceous plants including grasses. Woodland may form a transition to shrubland under drier conditions or during early stages of...
s and ponderosa pine
Ponderosa Pine
Pinus ponderosa, commonly known as the Ponderosa Pine, Bull Pine, Blackjack Pine, or Western Yellow Pine, is a widespread and variable pine native to western North America. It was first described by David Douglas in 1826, from eastern Washington near present-day Spokane...
forest
Forest
A forest, also referred to as a wood or the woods, is an area with a high density of trees. As with cities, depending where you are in the world, what is considered a forest may vary significantly in size and have various classification according to how and what of the forest is composed...
s, this flycatcher forages
Foraging
- Definitions and significance of foraging behavior :Foraging is the act of searching for and exploiting food resources. It affects an animal's fitness because it plays an important role in an animal's ability to survive and reproduce...
for insect
Insect
Insects are a class of living creatures within the arthropods that have a chitinous exoskeleton, a three-part body , three pairs of jointed legs, compound eyes, and two antennae...
s from shrub
Shrub
A shrub or bush is distinguished from a tree by its multiple stems and shorter height, usually under 5–6 m tall. A large number of plants may become either shrubs or trees, depending on the growing conditions they experience...
s or low tree
Tree
A tree is a perennial woody plant. It is most often defined as a woody plant that has many secondary branches supported clear of the ground on a single main stem or trunk with clear apical dominance. A minimum height specification at maturity is cited by some authors, varying from 3 m to...
branches.
The Gray Flycatcher is one of many species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
in the genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
Empidonax
Empidonax
The genus Empidonax is a group of small insect-eating passerine birds in the tyrant flycatcher family, the Tyrannidae.Most of these birds are remarkably similar in plumage: olive on the upper parts with light underparts, eye rings and wing bars...
. These species are very similar in appearance and behavior
Behavior
Behavior or behaviour refers to the actions and mannerisms made by organisms, systems, or artificial entities in conjunction with its environment, which includes the other systems or organisms around as well as the physical environment...
, and they are notoriously difficult to differentiate. The best characteristics for distinguishing these species are voice
Bird song
Bird vocalization includes both bird calls and bird songs. In non-technical use, bird songs are the bird sounds that are melodious to the human ear. In ornithology and birding, songs are distinguished by function from calls.-Definition:The distinction between songs and calls is based upon...
, breeding habitat
Habitat
* Habitat , a place where a species lives and grows*Human habitat, a place where humans live, work or play** Space habitat, a space station intended as a permanent settlement...
, and range
Range (biology)
In biology, the range or distribution of a species is the geographical area within which that species can be found. Within that range, dispersion is variation in local density.The term is often qualified:...
. The Gray Flycatcher, however, can be identified by a unique behavior
Behavior
Behavior or behaviour refers to the actions and mannerisms made by organisms, systems, or artificial entities in conjunction with its environment, which includes the other systems or organisms around as well as the physical environment...
, its downward tail wag. Other Empidonax species typically exhibit a rapid upward tail flick.
Description
Gray Flycatchers are small birdBird
Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...
s, but larger than most Empidonax flycatchers. A typical adult measures 15 cm (6 in) in length, 22 cm (9 in) in wingspan
Wingspan
The wingspan of an airplane or a bird, is the distance from one wingtip to the other wingtip. For example, the Boeing 777 has a wingspan of about ; and a Wandering Albatross caught in 1965 had a wingspan of , the official record for a living bird.The term wingspan, more technically extent, is...
, and 12.5 g (0.44 oz) in mass
Mass
Mass can be defined as a quantitive measure of the resistance an object has to change in its velocity.In physics, mass commonly refers to any of the following three properties of matter, which have been shown experimentally to be equivalent:...
.
Adults have pale gray upperparts, darker on the wing
Wing
A wing is an appendage with a surface that produces lift for flight or propulsion through the atmosphere, or through another gaseous or liquid fluid...
s and tail
Tail
The tail is the section at the rear end of an animal's body; in general, the term refers to a distinct, flexible appendage to the torso. It is the part of the body that corresponds roughly to the sacrum and coccyx in mammals, reptiles, and birds...
, with a faint olive tinge after molting in fall. Underparts are whitish, but washed slightly with yellow in fresh plumage
Plumage
Plumage refers both to the layer of feathers that cover a bird and the pattern, colour, and arrangement of those feathers. The pattern and colours of plumage vary between species and subspecies and can also vary between different age classes, sexes, and season. Within species there can also be a...
. They have white wing bars and an inconspicuous white eye ring. There is a pale supraloral band stretching above the base of the bill
Beak
The beak, bill or rostrum is an external anatomical structure of birds which is used for eating and for grooming, manipulating objects, killing prey, fighting, probing for food, courtship and feeding young...
. Relative to other North American Empidonax flycatchers, the Gray Flycatcher has a long, narrow bill, a long tail, and the mandible
Mandible
The mandible pronunciation or inferior maxillary bone forms the lower jaw and holds the lower teeth in place...
tends to be paler for more of its length.
Juveniles
Juvenile (organism)
A juvenile is an individual organism that has not yet reached its adult form, sexual maturity or size. Juveniles sometimes look very different from the adult form, particularly in terms of their colour...
are similar in appearance to adults, but with stronger olive and yellow tones. Also, young birds have buffy wing bars and brownish breasts.
Only the male sings. The song is a strong, two syllable note described as chuwip or wilip. A weaker, higher-pitched teeap or seep is often inserted into the song. Both sexes give a dry pit or wit call. Females call often when foraging
Foraging
- Definitions and significance of foraging behavior :Foraging is the act of searching for and exploiting food resources. It affects an animal's fitness because it plays an important role in an animal's ability to survive and reproduce...
or collecting nest materials.
Taxonomy
The Gray Flycatcher is very similar morphologicallyMorphology (biology)
In biology, morphology is a branch of bioscience dealing with the study of the form and structure of organisms and their specific structural features....
to the American Dusky Flycatcher (Empidonax oberholseri), which has been problematic in taxonomy
Taxonomy
Taxonomy is the science of identifying and naming species, and arranging them into a classification. The field of taxonomy, sometimes referred to as "biological taxonomy", revolves around the description and use of taxonomic units, known as taxa...
. When described as a species in 1889, the Gray Flycatcher was named Empidonax griseus. This name was reduced to synonymy
Synonym (taxonomy)
In scientific nomenclature, a synonym is a scientific name that is or was used for a taxon of organisms that also goes by a different scientific name. For example, Linnaeus was the first to give a scientific name to the Norway spruce, which he called Pinus abies...
when it was discovered that the type
Biological type
In biology, a type is one particular specimen of an organism to which the scientific name of that organism is formally attached...
specimen
Specimen
A specimen is a portion/quantity of material for use in testing, examination, or study.BiologyA laboratory specimen is an individual animal, part of an animal, a plant, part of a plant, or a microorganism, used as a representative to study the properties of the whole population of that species or...
designated for the Dusky Flycatcher was in fact a Gray Flycatcher. The name then in use for Dusky Flycatcher was Wright’s flycatcher (E. wrightii), a name proposed in 1858. Because the name wrightii took precedence, it was applied to the Gray Flycatcher, leaving the Dusky Flycatcher to be given a new name, E. oberholseri.
There are no recognized subspecies
Subspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
, and there is no geographic variation reported.
The International Ornithological Congress uses the name American Grey Flycatcher for Empidonax wrightii to differentiate it from the African Grey Flycatcher and the Ethiopian Grey Flycatcher. However, the American Ornithologists' Union (which covers North and Middle America) names it Gray Flycatcher.
Distribution
The Gray Flycatcher breeds from southernmost British ColumbiaBritish Columbia
British Columbia is the westernmost of Canada's provinces and is known for its natural beauty, as reflected in its Latin motto, Splendor sine occasu . Its name was chosen by Queen Victoria in 1858...
through a narrow zone in central Washington to eastern Oregon
Oregon
Oregon is a state in the Pacific Northwest region of the United States. It is located on the Pacific coast, with Washington to the north, California to the south, Nevada on the southeast and Idaho to the east. The Columbia and Snake rivers delineate much of Oregon's northern and eastern...
and California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
. The range extends east across Nevada
Nevada
Nevada is a state in the western, mountain west, and southwestern regions of the United States. With an area of and a population of about 2.7 million, it is the 7th-largest and 35th-most populous state. Over two-thirds of Nevada's people live in the Las Vegas metropolitan area, which contains its...
, southern Idaho
Idaho
Idaho is a state in the Rocky Mountain area of the United States. The state's largest city and capital is Boise. Residents are called "Idahoans". Idaho was admitted to the Union on July 3, 1890, as the 43rd state....
, Utah
Utah
Utah is a state in the Western United States. It was the 45th state to join the Union, on January 4, 1896. Approximately 80% of Utah's 2,763,885 people live along the Wasatch Front, centering on Salt Lake City. This leaves vast expanses of the state nearly uninhabited, making the population the...
, and northern Arizona
Arizona
Arizona ; is a state located in the southwestern region of the United States. It is also part of the western United States and the mountain west. The capital and largest city is Phoenix...
to southwestern Wyoming
Wyoming
Wyoming is a state in the mountain region of the Western United States. The western two thirds of the state is covered mostly with the mountain ranges and rangelands in the foothills of the Eastern Rocky Mountains, while the eastern third of the state is high elevation prairie known as the High...
, western Colorado
Colorado
Colorado is a U.S. state that encompasses much of the Rocky Mountains as well as the northeastern portion of the Colorado Plateau and the western edge of the Great Plains...
, and northwestern New Mexico
New Mexico
New Mexico is a state located in the southwest and western regions of the United States. New Mexico is also usually considered one of the Mountain States. With a population density of 16 per square mile, New Mexico is the sixth-most sparsely inhabited U.S...
.
Depending on latitude
Latitude
In geography, the latitude of a location on the Earth is the angular distance of that location south or north of the Equator. The latitude is an angle, and is usually measured in degrees . The equator has a latitude of 0°, the North pole has a latitude of 90° north , and the South pole has a...
, they arrive on breeding grounds mid-April to mid-May and leave between mid-August and mid-September. Migration
Bird migration
Bird migration is the regular seasonal journey undertaken by many species of birds. Bird movements include those made in response to changes in food availability, habitat or weather. Sometimes, journeys are not termed "true migration" because they are irregular or in only one direction...
between breeding and wintering grounds takes approximately seven weeks in both spring and autumn. Males usually arrive on breeding grounds one week prior to arrival of females.
The Gray Flycatcher winters in Baja California Sur
Baja California Sur
Baja California Sur , is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. Before becoming a state on October 8, 1974, the area was known as the South Territory of Baja California. It has an area of , or 3.57% of the land mass of Mexico and comprises...
, southeastern Arizona, and central Sonora
Sonora
Sonora officially Estado Libre y Soberano de Sonora is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided into 72 municipalities; the capital city is Hermosillo....
to central Oaxaca
Oaxaca
Oaxaca , , officially Estado Libre y Soberano de Oaxaca is one of the 31 states which, along with the Federal District, comprise the 32 federative entities of Mexico. It is divided into 571 municipalities; of which 418 are governed by the system of customs and traditions...
. Small numbers may winter in western Texas
Texas
Texas is the second largest U.S. state by both area and population, and the largest state by area in the contiguous United States.The name, based on the Caddo word "Tejas" meaning "friends" or "allies", was applied by the Spanish to the Caddo themselves and to the region of their settlement in...
and southern California.
Habitat
Breeding habitat can be shrublandShrubland
Shrubland, scrubland, scrub or brush is a plant community characterized by vegetation dominated by shrubs, often also including grasses, herbs, and geophytes. Shrubland may either occur naturally or be the result of human activity...
, open woodland, or forest with bare understory
Understory
Understory is the term for the area of a forest which grows at the lowest height level below the forest canopy. Plants in the understory consist of a mixture of seedlings and saplings of canopy trees together with understory shrubs and herbs...
. Although it is typically dominated by sagebrush (Artemisia
Artemisia (plant)
Artemisia is a large, diverse genus of plants with between 200 to 400 species belonging to the daisy family Asteraceae. It comprises hardy herbs and shrubs known for their volatile oils. They grow in temperate climates of the Northern Hemisphere and Southern Hemisphere, usually in dry or semi-dry...
spp), common associations include bitterbrush (Purshia
Purshia
Purshia is a small genus of 5-8 species of flowering plants in the family Rosaceae, native to western North America, where they grow in dry climates from southeast British Columbia in Canada south throughout the western United States to northern Mexico. The classification of Purshia within the...
spp), rabbitbrush (Chrysothamnus
Chrysothamnus
Chrysothamnus is a member of the plant family Asteraceae. It is a semi-deciduous shrub, sometimes also called sagebrush. The native distribution is in the arid western United States and northern Mexico...
spp, Ericameria
Ericameria
Ericameria is a genus of shrubs in the Asteraceae or daisy family known by the common names rabbitbrush, rabbitbush, and goldenbush. These are semi-deciduous shrubs familiarly known as to sagebrush. They are distributed in the arid western United States and northern Mexico. Bright yellow flowers...
nauseosus), mountain-mahogany (Cercocarpus ledifolius), juniper (Juniperus spp.), pinyon pine (Pinus spp.), and ponderosa pine (Pinus ponderosa).
During migration habitat is generally similar to breeding habitat, but riparian areas are often used. Thus, migrants may be found in willow (Salix spp.), oaks (Quercus spp.), or mesquite (Prosopis
Prosopis
Prosopis is a genus of flowering plants in the pea family, Fabaceae. It contains around 45 species of spiny trees and shrubs found in subtropical and tropical regions of the Americas, Africa, Western Asia, and South Asia. They often thrive in arid soil and are resistant to drought, on occasion...
spp.).
In winter the Gray Flycatcher is found in "arid open and semiopen areas with scrub and scattered trees".
Diet
The diet presumably consists entirely of insects and other small invertebrates. Fruit may be eaten in winter, but that has not been confirmed.Most prey is taken in flight
Hawking (birds)
Hawking is a feeding strategy in birds involving catching flying insects in the air. The term usually refers to a technique of sallying out from a perch to snatch an insect and then returning to the same or a different perch...
or from the ground. A bird will wait on an open perch – usually on a shrub or low tree branch – and fly out to catch a passing insect. Less commonly, a hovering bird gleans
Gleaning (birds)
Gleaning is a term for a feeding strategy by birds in which they catch invertebrate prey, mainly arthropods, by plucking them from foliage or the ground, from crevices such as rock faces and under the eaves of houses, or even, as in the case of ticks and lice, from living animals. This behavior is...
prey from foliage or bark
Bark
Bark is the outermost layers of stems and roots of woody plants. Plants with bark include trees, woody vines and shrubs. Bark refers to all the tissues outside of the vascular cambium and is a nontechnical term. It overlays the wood and consists of the inner bark and the outer bark. The inner...
.
Reproduction
The Gray Flycatcher is territorialTerritory (animal)
In ethology the term territory refers to any sociographical area that an animal of a particular species consistently defends against conspecifics...
during the breeding season. Males establish a territory and attract a female through vocalizations and displays. They appear to be monogamous, but extra-pair copulations may occur.
The nest
Bird nest
A bird nest is the spot in which a bird lays and incubates its eggs and raises its young. Although the term popularly refers to a specific structure made by the bird itself—such as the grassy cup nest of the American Robin or Eurasian Blackbird, or the elaborately woven hanging nest of the...
is bulky and less compact than those of other Empidonax flycatchers. The female builds the nest (males rarely help) from various plant materials, especially grass stalks and strips of bark. The nest is usually lined with softer materials, such as wool, hair, feathers, or soft grasses. Nests may be placed in sagebrush, bitterbrush, junipers, or pines. Nest height depends in part on the height of the substrate (i. e., nests tend to be higher in taller trees) but is usually 1–6 m (3–20 ft) above ground. Most nests are placed in the crotch of a branch next to the trunk, but some are situated on larger branches away from the trunk.
Females lay one egg
Egg (biology)
An egg is an organic vessel in which an embryo first begins to develop. In most birds, reptiles, insects, molluscs, fish, and monotremes, an egg is the zygote, resulting from fertilization of the ovum, which is expelled from the body and permitted to develop outside the body until the developing...
per day, with a final clutch size
Clutch (eggs)
A clutch of eggs refers to all the eggs produced by birds or reptiles, often at a single time, particularly those laid in a nest.In birds, destruction of a clutch by predators, , results in double-clutching...
of three or four. The female incubates
Avian incubation
Incubation refers to the process by which certain oviparous animals hatch their eggs, and to the development of the embryo within the egg. The most vital factor of incubation is the constant temperature required for its development over a specific period. Especially in domestic fowl, the act of...
the eggs for about two weeks. The eggs, although laid on different days, usually hatch on the same day. The chicks are altricial
Altricial
Altricial, meaning "requiring nourishment", refers to a pattern of growth and development in organisms which are incapable of moving around on their own soon after hatching or being born...
and have little down when they hatch. Both parents feed the nestlings. Fledging
Fledge
Fledge is the stage in a young bird's life when the feathers and wing muscles are sufficiently developed for flight. It also describes the act of a chick's parents raising it to a fully grown state...
occurs about 16 days after hatching.
External links
- Gray Flycatcher photo gallery VIREO Photo-High Res--(Close-up)
- Photo-High Res--(Close-up); Article – www-personal.ksu.edu-(Photo gallery–Utah Birds)
