Editing Ruby-throated hummingbird

{{short description|Species of bird}}
{{Use dmy dates|date=February 2020}}
{{Speciesbox
| name = Ruby-throated hummingbird
| image = Archilochus colubris -flying -male-8.jpg
| image_caption = Male
| image2 = Ruby-throated hummingbird (Archilochus colubris) female Palopo.jpg
| image2_caption =Female
| status = LC
| status_system = IUCN3.1
| status_ref =<ref name="iucn">{{cite web |title=Ruby-throated hummingbird |url=https://www.iucnredlist.org/species/22688193/186910664 |publisher=International Union for Conservation of Nature's Red List of Threatened Species |access-date=22 April 2023 |date=2023}}</ref>
| status2 = CITES_A2 
| status2_system = CITES 
| status2_ref =<ref>{{Cite web|title=Appendices {{!}} CITES|url=https://cites.org/eng/app/appendices.php|access-date=2022-01-14|website=cites.org}}</ref>
| genus = Archilochus
| species = colubris
| authority = ([[Carl Linnaeus|Linnaeus]], [[10th edition of Systema Naturae|1758]])
| range_map = Archilochus colubris map.svg
| range_map_caption = Approximate distribution map
{{leftlegend|#f18e08|Breeding}}
{{leftlegend|#ffd42a|Migration}}
{{leftlegend|#5f9ed3|Non-breeding}}
| synonyms = ''Trochilus colubris'' {{small|Linnaeus,&nbsp;1758}}
}}

The '''ruby-throated hummingbird''' ('''''Archilochus colubris''''') is a species of [[hummingbird]] that generally spends the winter in Central America, Mexico, and Florida, and migrates to Canada and other parts of Eastern North America for the summer to breed. It is the most common hummingbird in eastern North America, having population estimates of about 35 million in 2021.

==Taxonomy==
The ruby-throated hummingbird was [[Species description|formally described]] by the Swedish naturalist [[Carl Linnaeus]] in 1758 in the [[10th edition of Systema Naturae|tenth edition]] of his ''[[Systema Naturae]]'' under the [[binomial nomenclature|binomial name]] ''Trochilus colubris''.<ref>{{cite book | last=Linnaeus | first=Carl | authorlink=Carl Linnaeus | year=1758 | title= Systema Naturae per regna tria naturae, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis | volume=1 | edition=10th | page=120 | publisher=Laurentii Salvii | place=Holmiae (Stockholm) | language=Latin | url=https://www.biodiversitylibrary.org/page/727025 }}</ref> Linnaeus based his description on the earlier account by [[Mark Catesby]] in his ''The Natural History of Carolina, Florida and the Bahama Islands'' that had been published in 1729 and that by [[George Edwards (naturalist)|George Edwards]] in his ''A Natural History of Uncommon Birds'' that had been published in 1743.<ref>{{ cite book | last=Catesby  | first=Mark | author-link=Mark Catesby | year=1729 | title=The Natural History of Carolina, Florida and the Bahama Islands | volume=1 | place=London | publisher=W. Innys and R. Manby | language=English, French | page=65 | url=https://www.biodiversitylibrary.org/page/40753313 }}</ref><ref>{{ cite book | last=Edwards | first=George | author-link=George Edwards (naturalist) | year=1743 | title=A Natural History of Uncommon Birds | place=London | publisher=Printed for the author at the College of Physicians | volume=Part 1 | page=38, Plate 38 | url=https://www.biodiversitylibrary.org/page/50240660 }}</ref> The [[type locality (biology)|type locality]] is [[South Carolina]].<ref>{{ cite book | editor-last=Peters | editor-first=James Lee | editor-link=James L. Peters | year=1945 | title=Check-List of Birds of the World | volume=5 | publisher=Harvard University Press | place=Cambridge, Massachusetts  | page=134 | url=https://www.biodiversitylibrary.org/page/14480145 }}</ref> The specific epithet ''colubris'' is from the Spanish ''colibrí'' meaning "hummingbird".<ref>{{cite book | last=Jobling | first=James A. | year=2010| title=The Helm Dictionary of Scientific Bird Names | publisher=Christopher Helm | location=London | isbn=978-1-4081-2501-4 | page=114 }}</ref> The ruby-throated hummingbird is now placed in the [[genus]] ''[[Archilochus (bird)|Archilochus]]'' that was introduced in 1854 by the German naturalist [[Ludwig Reichenbach]].<ref>{{ cite journal | last=Reichenbach | first=Ludwig | author-link=Ludwig Reichenbach | year=1854 | title=Aufzählung der Colibris Oder Trochilideen in ihrer wahren natürlichen Verwandtschaft, nebst Schlüssel ihrer Synonymik | journal=Journal für Ornithologie (Supplement) | volume=1 | pages=1–24 [13] | language=German | url=https://www.biodiversitylibrary.org/page/13867391 }}</ref><ref name=ioc>{{cite web| editor1-last=Gill | editor1-first=Frank | editor1-link=Frank Gill (ornithologist) | editor2-last=Donsker | editor2-first=David | editor3-last=Rasmussen | editor3-first=Pamela | editor3-link=Pamela Rasmussen | date=January 2021 | title=Hummingbirds | work=IOC World Bird List Version 11.1 | url=http://www.worldbirdnames.org/bow/hummingbirds/ | publisher=International Ornithologists' Union | access-date=30 January 2021 }}</ref> The species is [[monotypic]]: no [[subspecies]] are recognised.<ref name=ioc/>

== Description ==
This hummingbird is from {{convert|7|to|9|cm|in|abbr=on}} long and has an {{convert|8|to|11|cm|in|abbr=on}} wingspan. Weight can range from {{convert|2|to|6|g|oz|abbr=on}}, with males averaging {{convert|3.4|g|oz|abbr=on}} against the slightly larger female which averages {{convert|3.8|g|oz|abbr=on}}.<ref name="Cornell">{{cite web|url=http://www.allaboutbirds.org/guide/Ruby-throated_Hummingbird/overview |title=Ruby-throated hummingbird|publisher=All About Birds – Cornell University Laboratory of Ornithology|date=2023|access-date=27 April 2023}}</ref><ref>{{cite web|last=Kirschbaum |first=Kari |url=http://animaldiversity.org/site/accounts/information/Archilochus_colubris.html |title=ADW: Archilochus colubris: INFORMATION |publisher=Animaldiversity.org |access-date=7 November 2012}}</ref> Adults are metallic green above and grayish white below, with near-black wings. Their bill, at up to {{convert|2|cm|in|abbr=on}}, is long, straight, and slender. 

[[File:Ruby Throated Hummingbird, F, leg, 430 ESt. NW, 8.22.12 2013-04-12-14.49.36 ZS PMax (8644622066).jpg|thumb|Close-up of toe arrangement in a ruby-throated hummingbird foot, showing three claw-like toes forward and one backward.]]
Hummingbird legs are short and have [[Bird_feet_and_legs#Tarsometatarsus|feet with three toes pointing forward and one backward]] {{ndash}} the [[hallux]].<ref name="b&b">{{cite web |first1=Emily |last1=Hannemann |title=Hummingbird feet: Can hummingbirds walk? |url=https://www.birdsandblooms.com/birding/attracting-hummingbirds/hummingbird-feet/ |publisher=Birds&Blooms |access-date=4 April 2023 |date=12 May 2022}}</ref><ref name="scoop">{{cite web |title=Do hummingbirds have feet? |url=https://www.wildbirdscoop.com/do-hummingbirds-have-feet.html |publisher=Wild Bird Scoop |access-date=4 April 2023 |date=2023}}</ref> The toes are formed as [[claw]]s (image) with ridged inner surfaces to aid gripping onto flower stems or petals.
The middle toe is around {{convert|0.6|cm|in|abbr=on}}. The ruby-throated hummingbird can only shuffle to move along a branch, although it can [[Preening#Preening_action|scratch-preen]] with its feet.<ref name= Cornell/><ref>{{cite web|url=http://www.rubythroat.org/RTHUAudubonTextMain.html |title=John James Audubon's Description of the Ruby-throated Hummingbird |publisher=Rubythroat.org |access-date=7 November 2012}}</ref>

The species is [[Sexual dimorphism|sexually dimorphic]].<ref>{{cite web|url=http://www.rubythroat.org/RTHUExternalMain.html |title=Hummingbird: external appearance, ageing, sexing |publisher=Ruby-Throat.org |access-date=13 June 2011}}</ref> The adult male has a [[gorget (bird)|gorget]] (throat patch) of iridescent ruby red bordered narrowly with velvety black on the upper margin and a forked black tail with a faint violet sheen. The red iridescence is highly directional and appears dull black from many angles. The female has a notched tail with outer feathers banded in green, black, and white and a white throat that may be plain or lightly marked with dusky streaks or stipples. Males are smaller than females and have slightly shorter bills. Juvenile males resemble adult females, though usually with heavier throat markings.<ref name=williamson2001>Williamson (2001)</ref> The plumage is [[molt]]ed once a year on the wintering grounds, beginning in early fall and ending by late winter.<ref>{{Cite journal|last=Baltosser|first=William H.|date=1995|title=Annual Molt in Ruby-throated and Black-chinned Hummingbirds|url=https://sora.unm.edu/sites/default/files/journals/condor/v097n02/p0484-p0491.pdf|journal=The Condor|volume=97|issue=2|pages=484–491|via=Searchable Ornithological Research Archive|doi=10.2307/1369034|jstor=1369034}}</ref>

===Population and status===
As of 2021, there were 34–36&nbsp;million ruby-throated hummingbirds over their eastern North American breeding range, making this species the most populous of North American hummingbirds.<ref name=iucn/><ref name="abc">{{cite web |first1=Kathryn |last1=Stonich |title=Hummingbirds of the United States: A Photo List of All Species |url=https://abcbirds.org/blog21/types-of-hummingbirds/ |publisher=American Bird Conservancy |access-date=7 March 2023 |date=26 April 2021}}</ref> Despite substantial population growth from 1970 through the early 21st century, numbers of ruby-throated birds declined by 17% over the census reported in 2021.<ref name="English">{{cite journal |last1=English |first1=Simon G. |last2=Bishop |first2=Christine A. |last3=Wilson |first3=Scott |last4=Smith |first4=Adam C. |title=Current contrasting population trends among North American hummingbirds |journal=Scientific Reports |volume=11 |issue=1 |date=2021-09-15 |page=18369 |issn=2045-2322 |doi=10.1038/s41598-021-97889-x |pmid=34526619 |pmc=8443710 |bibcode=2021NatSR..1118369E }}</ref> According to the [[IUCN Red List|International Union for Conservation of Nature Red List of Threatened Species]] in 2023, ruby-throated hummingbirds are listed as [[Least-concern species|''least-concern'']] for risk of [[extinction]],<ref name=iucn/> while [[Hummingbird#Population_estimates_and_threatened_species|numerous other common North American hummingbirds are in significant decline]].<ref name=English/>

===Vocalization ===
{{Listen
|filename=Archilochus colubris.ogg
|title=''Archilochus colubris'' call
|description=Chirping of a ruby-throated hummingbird (''Archilochus colubris'')
|format=[[Ogg]]}}

The vocalizations of ruby-throated hummingbirds are rapid, squeaky chirps, which are used primarily for threats. For example, males may vocalize to warn another male that has entered his territory.

During the courtship displays, the male makes a rapid ''tik-tik tik-tik tik-tik'' sound with his wings.<ref>{{cite journal|pmid=21903810|year=2011|last1=Clark|first1=C. J.|title=Aeroelastic flutter produces hummingbird feather songs|journal=Science|volume=333|issue=6048|pages=1430–3|last2=Elias|first2=D. O.|last3=Prum|first3=R. O.|doi=10.1126/science.1205222|bibcode=2011Sci...333.1430C |s2cid=12248122|url=http://prumlab.yale.edu/sites/default/files/clark_et_al._2011_som.pdf}}</ref> The sound is produced both during the shuttle display, at each end of the side-to-side flight. Also, the sound is made during dive displays. A second, rather faint, repeated whining sound is sometimes produced with the outer tail-feathers during the dive, as the male flies over the female, spreading and shutting the tail as he does so.

== Distribution and habitat ==
The breeding habitat is throughout most of the Eastern United States and south-central and southeastern Canada in deciduous and pine forests and forest edges, orchards, and gardens. The female builds a nest in a protected location in a shrub or a tree. Of all hummingbirds in the United States, this species has the largest breeding range.<ref name=Cornell/>

The ruby-throated hummingbird is [[bird migration|migratory]], spending most of the winter in Florida, southern Mexico and Central America,<ref name=Hargrove>{{Cite journal
 | pmid = 16351726
| year = 2005
| last1 = Hargrove
| first1 = J. L.
| title = Adipose energy stores, physical work, and the metabolic syndrome: Lessons from hummingbirds
| journal = Nutrition Journal
| volume = 4
| pages = 36
| doi = 10.1186/1475-2891-4-36
| pmc = 1325055
| doi-access = free
}}</ref> as far south as extreme western [[Panama]],<ref name=robinsonetal1996>Robinson ''et al.'' (1996)</ref> and the [[West Indies]]. During migration, some birds embark on a nonstop 900-mile journey across the [[Gulf of Mexico]] and [[Caribbean]] from [[Panama]] or Mexico to the eastern United States.<ref name=Hargrove/> The bird breeds throughout the eastern United States, east of the 100th meridian, and in southern Canada, particularly [[Ontario]], in eastern and mixed deciduous and broadleaved forest.<ref name="Mighigan">{{cite web
  | last1 =Harris  | first1 =M.
  |first2=R.|last2=Naumann|first3=K.|last3=Kirschbaum
  | title =''Archilochus colubris''
  | publisher =University of Michigan Museum of Zoology
  | url =http://animaldiversity.org/site/accounts/information/Archilochus_colubris.html
  | access-date = 24 August 2007 }}
</ref><ref>{{cite web|url=http://www.ontariohummingbirds.ca/migrationrange_maps.php|title=The Ontario hummingbird project: migration and range maps|publisher=The Ontario Hummingbird Project|date=2013|access-date=23 March 2014|url-status=dead|archive-url=https://web.archive.org/web/20140403153408/http://www.ontariohummingbirds.ca/migrationrange_maps.php|archive-date=3 April 2014}}</ref> In winter, it is seen mostly in Mexico and Florida.

During migration southward in autumn along the northern coast of the Gulf of Mexico, older male and female birds were better prepared for long-distance flight than first-year birds by having higher body weights and larger fuel loads.<ref name=zenzal>{{Cite journal | last1=Zenzal | first1=Theodore J. Jr. | last2=Moore | first2=Frank R. | date=2016 | title=Stopover biology of Ruby-throated Hummingbirds (''Archilochus colubris'') during autumn migration | journal=The Auk | volume=133 | issue=2 | pages=237–250 | doi=10.1642/AUK-15-160.1 | doi-access=free }}</ref>

== Behavior and ecology ==
[[File:Archilochus colubris Illinois (4667079265).jpg|thumb|left|Male (lower left) displaying its prominent gorget and a female ruby-throated hummingbird]]
Ruby-throated hummingbirds are [[wikt:solitary|solitary]]. Adults of this species are not social, other than during courtship (which lasts a few minutes); the female also cares for her offspring. Both males and females of any age are aggressive toward other hummingbirds. They may defend territories, such as a feeding territory, attacking and chasing other hummingbirds that enter.

As part of their spring migration, portions of the population fly from the [[Yucatan Peninsula]] of Mexico across the [[Gulf of Mexico]], arriving first in Florida and [[Louisiana]].<ref name=Hargrove/> This feat is impressive, as an {{convert|800|km|abbr = on}}, non-stop flight over water would seemingly require a caloric energy that far exceeds an adult hummingbird's body weight of {{Convert|3|g|abbr = on}}.<ref name=Hargrove/> However, researchers discovered the tiny birds can double their fat mass in preparation for their Gulf crossing,<ref name=zenzal/> then expend the entire calorie reserve from fat during the 20-hour non-stop crossing when food and water are unavailable.<ref name=Hargrove/><ref name=zenzal/>

Hummingbirds have one of the highest metabolic rates of any animal, with heart rates up to 1260 beats per minute, breathing rate of about 250 breaths per minute even at rest, and oxygen consumption of about 4 ml oxygen/g/hour at rest.<ref>{{Cite journal
 | pmid = 1612136
| year = 1992
| last1 = Suarez
| first1 = R. K.
| title = Hummingbird flight: Sustaining the highest mass-specific metabolic rates among vertebrates
| journal = Experientia
| volume = 48
| issue = 6
| pages = 565–70
 | doi=10.1007/bf01920240
| s2cid = 21328995
}}</ref> During flight, hummingbird oxygen consumption per gram of muscle tissue is approximately 10 times higher than that seen for elite human athletes.<ref name=Hargrove/>

They feed frequently while active during the day. When temperatures drop, particularly on cold nights, they may conserve energy by entering [[Hypothermia|hypothermic]] [[Wiktionary:torpid|torpor]].<ref name=Hargrove/>

=== Flight ===
Hummingbirds have many skeletal and flight muscle adaptations which allow great agility in flight. Muscles make up 25–30% of their body weight, and they have long, blade-like wings that, unlike the wings of other birds, connect to the body only from the shoulder joint.<ref name="hedrick">{{cite journal|title=Morphological and kinematic basis of the hummingbird flight stroke: scaling of flight muscle transmission ratio|journal=Proc Biol Sci|year=2011|volume= 22279|issue=1735|pages=1986–1992|doi=10.1098/rspb.2011.2238|pmid=22171086|pmc=3311889|last1=Hedrick|first1=T. L.|last2=Tobalske|first2=B. W.|last3=Ros|first3=I. G.|last4=Warrick|first4=D. R.|last5=Biewener|first5=A. A.}}</ref> This adaptation allows the wing to rotate almost 180°, enabling the bird to fly not only forward but backward, and to [[hovering flight|hover in mid-air]], flight capabilities that are similar to insects and unique among birds.<ref name=hedrick/>

The main wing bone, the [[humerus]], is specifically adapted for hovering flight. Hummingbirds have a relatively short humerus with proportionally massive [[deltoid muscle|deltoid]]-[[pectoralis major muscle|pectoral]] muscles which permit pronounced wing [[supination]] during upstroke when hovering.<ref name="tobalske1">{{Cite journal | pmid = 20581281| year = 2010| last1 = Tobalske| first1 = B. W.| title = Effects of flight speed upon muscle activity in hummingbirds| journal = Journal of Experimental Biology| volume = 213| issue = Pt 14| pages = 2515–23| last2 = Biewener| first2 = A. A.| last3 = Warrick| first3 = D. R.| last4 = Hedrick| first4 = T. L.| last5 = Powers| first5 = D. R.| doi = 10.1242/jeb.043844| s2cid = 9349200| url = https://dash.harvard.edu/bitstream/handle/1/4892998/Tobalske_EffectsFlight.pdf?sequence=1| doi-access = free| bibcode = 2010JExpB.213.2515T}}</ref>

A hummingbird's ability to hover is due to its small mass, high wingbeat frequency and relatively large margin of mass-specific power available for flight. Several anatomical features contribute further, including proportionally massive major flight muscles ([[pectoralis major muscle|pectoralis major]] and [[supracoracoideus]]) and wing anatomy that enables the bird to leave its wings extended yet turned over ([[supine]]) during the upstroke. This generates lift that supports body weight and maneuvering.<ref name="tobalske2">{{cite journal|title=Hovering and intermittent flight in birds|author=Tobalske BW|journal=Bioinspir Biomim|year=2010|volume=5|issue=4|page=045004|doi=10.1088/1748-3182/5/4/045004|pmid=21098953|bibcode=2010BiBi....5d5004T |s2cid=9719885}}</ref>

Hummingbirds achieve ability to support their weight and hover from wing beats creating lift on the downstroke of a wing flap and also on the upstroke in a ratio of 75%:25%, respectively, similarly to an insect.<ref name=tobalske2/><ref name="warrick">{{cite journal|vauthors=Warrick DR, Tobalske BW, Powers DR |year=2005 |title=Aerodynamics of the hovering hummingbird |journal=Nature |volume=435 |issue=23 June 7045 |pages=1094–7 |doi=10.1038/nature03647 |pmid=15973407|bibcode=2005Natur.435.1094W |s2cid=4427424 |url=https://digitalcommons.georgefox.edu/cgi/viewcontent.cgi?article=1033&context=bio_fac |url-access=subscription }}</ref> Hummingbirds and insects gain lift during hovering partially through inversion of their cambered wings during an upstroke.<ref name=warrick/> During hovering, hummingbird wings beat up to 80 times per second.<ref name="bbc">{{cite web|author=Gill V|publisher=BBC News|url=https://www.bbc.com/news/28563737|title=Hummingbirds edge out helicopters in hover contest|date=30 July 2014|access-date=1 September 2014}}</ref>

=== Food and feeding ===
[[File:RubyThroatedHummingbird(Crop).jpg|thumb|left|Female feeding on nectar from scarlet beebalm (''[[Monarda didyma]]'')]]

Nectar from [[flower]]s and flowering trees, as well as small insects and spiders, are its main food.<ref>{{Cite web |title=Ruby-throated Hummingbird {{!}} Audubon Field Guide |url=https://www.audubon.org/field-guide/bird/ruby-throated-hummingbird |access-date=2024-04-25 |website=Audubon |language=en}}</ref> Although hummingbirds are well known to feed on nectar, small [[arthropod]]s are an important source part of protein, minerals, and vitamins in the diet of adult hummingbirds. Hummingbirds show a slight preference for red, orange, and bright pink [[Cylinder (geometry)|tubular]] flowers as [[nectar]] sources, though flowers not [[Ornithophilous|adapted to hummingbird pollination]] (e.g., [[willow]] catkins) are also visited.<ref name="robinsonetal1996"/> Their diet may also occasionally include sugar-rich tree [[sap]] taken from [[sapsucker]] wells. The birds feed from flowers using a long, extendable tongue and catch insects on the wing or glean them from flowers, leaves, bark, and spiders' webs.

Young birds are fed insects for [[protein]] since nectar is an insufficient source of protein for the growing birds.<ref name="robinsonetal1996"/>

=== Breeding ===
[[File:Ruby-throated hummingbird on nest 01.jpg|thumb|Female ruby-throated hummingbird on nest]]
As typical for their family, ruby-throated hummingbirds are thought to be [[Polygyny in animals|polygynous]]. [[Polyandry in animals|Polyandry]] and [[polygynandry]] may also occur. They do not form breeding pairs, with males departing immediately after the reproductive act and females providing all parental care.<ref>{{cite web|author=Lanny Chambers |url=http://www.hummingbirds.net/rubythroated.html |title=Ruby-throated Hummingbird |publisher=Hummingbirds.net |access-date=13 June 2011}}</ref>

Males arrive at the breeding area in the spring and establish a [[Territory (animal)|territory]] before the females arrive. When the females return, males court females that enter their territory by performing courtship displays. They perform a "dive display" rising {{Convert|2.45|-|3.1|m|ft|abbr = on}} above and {{Convert|1.52|-|1.82|m|ft|abbr = on}} to each side of the female. If the female perches, the male begins flying in very rapid horizontal [[Arc (geometry)|arc]]s less than {{Convert|0.5|m|ft|abbr = on}} in front of her. If the female is receptive to the male, she may give a call and assume a solicitous posture with her tail feathers cocked and her wings drooped.<ref>{{Cite journal |last1=Hogan |first1=Benedict G. |last2=Stoddard |first2=Mary Caswell |date=2018-12-18 |title=Synchronization of speed, sound and iridescent color in a hummingbird aerial courtship dive |journal=Nature Communications |language=en |volume=9 |issue=1 |page=5260 |doi=10.1038/s41467-018-07562-7 |issn=2041-1723 |pmc=6299134 |pmid=30563977|bibcode=2018NatCo...9.5260H }}</ref>

The nest is usually constructed on a small, downward-sloping tree limb {{convert|3.1|to|12.2|m|ft|abbr=on}} feet above the ground. Favored trees are usually [[deciduous]], such as [[oak]], [[hornbeam]], [[birch]], [[Populus|poplar]] or [[Celtis|hackberry]], although [[pine]]s have also been used. Nests have even been found on loops of chain, wire, and extension cords.<ref name= Cornell/> The nest is composed of [[bud]] scales, with [[lichen]] on the exterior, bound with spider's silk, and lined with fibers such as plant down (often [[dandelion]] or [[thistle]] down) and animal hair. Most nests are well camouflaged. Old nests may be occupied for several seasons, but are repaired annually.<ref name="robinsonetal1996"/> As in all known hummingbird species, the female alone constructs the nest and cares for the eggs and young.

Females lay two (with a range of 1 to 3) white eggs about {{convert|12.9|x|8.5|mm|in|abbr=on}} in size and produce one to two broods each summer.<ref name= Cornell/> They [[avian incubation|brood]] the chicks over a period of 12 to 14 days, by which point they are feathered and [[Homeothermy|homeothermic]]. The female feeds the chicks from 1 to 3 times every hour by regurgitation, usually while the female continues hovering. When they are 18 to 22 days old, the young leave the nest and make their first flight.<ref name="robinsonetal1996"/>

== Longevity and mortality ==
[[File:Composite-ruby-throated-hummingbird.jpg|thumb|300px|Female ruby-throated hummingbird taking various defensive and evasive actions around a man-made feeder.]]
The oldest known ruby-throated hummingbird to be banded was 9 years and 1 month of age. Almost all hummingbirds of 7 years or more in age are females, with males rarely surviving past 5 years of age. Reasons for higher mortality in males may include loss of weight during the breeding season due to the high energetic demands of defending a territory followed by energetically costly migration.<ref name=Hargrove/>

A variety of animals prey on hummingbirds given the opportunity. Due to their small size, hummingbirds are vulnerable even to [[passerine]] birds and other animals which generally feed on insects. On the other hand, only very swift predators can capture them and a free-flying adult hummingbird is too nimble for most predators. Chief among their predators are the smaller, swifter [[raptor (bird)|raptors]] like [[sharp-shinned hawk]]s, [[Merlin (bird)|merlin]]s, [[American kestrel]]s and [[Mississippi kite]]s as well as [[domestic cat]]s, [[loggerhead shrike]]s and even [[greater roadrunner]]s, all of which are likely to ambush the hummingbird while it sits or sleeps on a perch or are distracted by breeding or foraging activities. Predatory lizards and bird-eating snakes may also prey on the species, especially on its tropical wintering grounds. Even large, predatory [[invertebrate]]s have preyed on ruby-throated hummingbirds, including [[praying mantis]]es (which have been seen to ambush adult hummingbirds at hummingbird feeders on more than one occasion), [[orb-weaver spider]]s, and [[green Darner]]s. [[Blue jay]]s are common predators of nests, as are several other [[corvid]]s in addition to some [[icterid]]s, bats, squirrels and [[chipmunk]]s.<ref>{{cite web|last=Kirschbaum |first=Kari |url=http://animaldiversity.org/site/accounts/information/Archilochus%20colubris.html |title=ADW: Archilochus colubris: INFORMATION |publisher=Animaldiversity.org |access-date=7 November 2012}}</ref><ref>{{cite web|url=http://www.rubythroat.org/QuestionsPredators01.html |title=Hummingbirds: Predators 1 |publisher=Rubythroat.org |access-date=7 November 2012}}</ref><ref>{{cite web|url=http://www.birdwatchersdigest.com/bwdsite/learn/hummingbirds/mantis-hummer.php# |title=Praying Mantis Makes Meal of a Hummingbird &#124; Bird Watcher's Digest |publisher=Birdwatchersdigest.com |access-date=7 November 2012}}</ref><ref>Weidensaul, Scott, T. R. Robinson, R. R. Sargent and M. B. Sargent. 2013. ''Ruby-throated Hummingbird (Archilochus colubris)'', The Birds of North America Online (A. Poole, Ed.). Ithaca: Cornell Lab of Ornithology.</ref>

==Gallery==
<gallery>
File:Brooklyn Museum - Ruby-throated Humming Bird - John J. Audubon.jpg|Brooklyn Museum - Ruby-throated hummingbird and [[trumpet creeper]] (''Campsis radicans'') - John J. Audubon
File:Ruby-throated Hummingbird (Archilochus colubris) RWD4.jpg|Female ruby-throated hummingbird nectaring on [[coral honeysuckle]] (''Lonicera sempervirens''), [[North Carolina]]
File:Ruby-Throated Hummingbird.png|Male ruby-throated hummingbird perched on a branch, displaying its tongue, [[East Texas]]
File:Ruby-throated hummingbird building a nest (71612).webm|Nest building
</gallery>

== References ==
{{Reflist}}

==Further reading==
* Robinson, T. R., R. R. Sargent, and M. B. Sargent (1996). Ruby-throated Hummingbird (''Archilochus colubris''). In ''The Birds of North America''. No. 204 (A. Poole and F. Gill, eds.). The Birds of North America, Inc., Philadelphia, PA.
* Williamson, S. L. (2001). ''A Field Guide to Hummingbirds of North America'' (Peterson Field Guide Series). Houghton Mifflin. Co., Boston, MA.

== External links ==
{{Commons and category|Archilochus colubris|Archilochus colubris}}
{{Wikispecies|Archilochus colubris}}

* {{InternetBirdCollection|ruby-throated-hummingbird-archilochus-colubris|Ruby-throated hummingbird}} eBird, Cornell University Laboratory of Ornithology, 2024
* {{VIREO|Ruby-throated+hummingbird|Ruby-throated hummingbird}}, The Academy of Natural Sciences, 2015

{{Taxonbar|from=Q834843}}

[[Category:Archilochus (bird)|ruby-throated hummingbird]]
[[Category:Birds of Canada]]
[[Category:Native birds of the Eastern United States]]
[[Category:Birds of the Caribbean]]
[[Category:Birds of the Dominican Republic]]
[[Category:Birds described in 1758|ruby-throated hummingbird]]
[[Category:Taxa named by Carl Linnaeus|ruby-throated hummingbird]]