The rufous hummingbird (''Selasphorus rufus'') is a small

hummingbird Hummingbirds are birds native to the Americas and comprise the Family (biology), biological family Trochilidae. With approximately 366 species and 113 genus, genera, they occur from Alaska to Tierra del Fuego, but most species are found in Cen ...

, about long with a long, straight and slender bill. These birds are known for their extraordinary flight skills, flying during their migratory transits. It is one of nine species in the

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

'' Selasphorus''.

Taxonomy

The rufous hummingbird was formally described in 1788 by the German naturalist

Johann Friedrich Gmelin Johann Friedrich Gmelin (8 August 1748 – 1 November 1804) was a German natural history, naturalist, chemist, botanist, entomologist, herpetologist, and malacologist. Education Johann Friedrich Gmelin was born as the eldest son of Philipp F ...

in his revised and expanded edition of

Carl Linnaeus Carl Linnaeus (23 May 1707 – 10 January 1778), also known after ennoblement in 1761 as Carl von Linné,#Blunt, Blunt (2004), p. 171. was a Swedish biologist and physician who formalised binomial nomenclature, the modern system of naming o ...

's ''

Systema Naturae ' (originally in Latin written ' with the Orthographic ligature, ligature æ) is one of the major works of the Sweden, Swedish botanist, zoologist and physician Carl Linnaeus (1707–1778) and introduced the Linnaean taxonomy. Although the syste ...

''. He placed it with all the other hummingbirds in the

Trochilus The streamertails are hummingbirds in the genus ''Trochilus'' that are endemic to Jamaica. It is the type genus of the family Trochilidae. Today, most authorities consider the two taxa in this genus as separate species, but some (e.g. AOU) conti ...

'' and coined the

binomial name In taxonomy, binomial nomenclature ("two-term naming system"), also called binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, both of which use Latin grammatical forms, altho ...

''Trochilus rufus''. Gmelin based his description on the ruff-necked hummingbird described by John Latham in 1782 and the ruffed honeysucker described by

Thomas Pennant Thomas Pennant (16 December 1798) was a Welsh natural history, naturalist, traveller, writer and antiquarian. He was born and lived his whole life at his family estate, Downing Hall, near Whitford, Flintshire, in Wales. As a naturalist he had ...

in 1785. The type locality given by Gmelin was

Nootka Sound Nootka Sound () is a sound of the Pacific Ocean on the rugged west coast of Vancouver Island, in the Pacific Northwest, historically known as King George's Sound. It separates Vancouver Island and Nootka Island, part of the Canadian province of ...

on the west coast of

Vancouver Island Vancouver Island is an island in the northeastern Pacific Ocean and part of the Canadian province of British Columbia. The island is in length, in width at its widest point, and in total area, while are of land. The island is the largest ...

in western Canada, although breeding was estimated to occur in northwestern North America and wintering in westcentral Mexico. The rufous hummingbird is now placed with eight other species in the genus '' Selasphorus'' that was introduced in 1832 by the English naturalist

William Swainson William Swainson Fellow of the Linnean Society, FLS, Fellow of the Royal Society, FRS (8 October 1789 – 6 December 1855), was an English ornithologist, Malacology, malacologist, Conchology, conchologist, entomologist and artist. Life Swains ...

. The genus name combines the

Ancient Greek Ancient Greek (, ; ) includes the forms of the Greek language used in ancient Greece and the classical antiquity, ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Greek ...

''selas'' meaning "light" or "flame" with ''-phoros'' meaning "-carrying". The specific epithet ''rufus'' is the Latin word for "red". The species is considered as

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unisp ...

: no

subspecies In Taxonomy (biology), biological classification, subspecies (: subspecies) is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (Morphology (biology), morpholog ...

are recognized.

Description

The adult male has a white breast,

rufous Rufous () is a color that may be described as reddish-brown or brownish- red, as of rust or oxidised iron. The first recorded use of ''rufous'' as a color name in English was in 1782. However, the color is also recorded earlier in 1527 as a d ...

face, flanks and tail and an

iridescent Iridescence (also known as goniochromism) is the phenomenon of certain surfaces that appear gradually to change colour as the angle of view or the angle of illumination changes. Iridescence is caused by wave interference of light in microstruc ...

orange-red throat patch or gorget. Some males have some green on their back and/or crown. The female has green, white, and some iridescent orange

feather Feathers are epidermal growths that form a distinctive outer covering, or plumage, on both avian (bird) and some non-avian dinosaurs and other archosaurs. They are the most complex integumentary structures found in vertebrates and an exa ...

s in the center of the throat, and a dark tail with white tips and rufous base. The female is slightly larger than the male. Females and the rare green-backed males are extremely difficult to differentiate from Allen's hummingbird. The typical "notched" shape of the second rectrix (R2) is considered an important field mark to distinguish the adult male rufous hummingbird from the adult male Allen's hummingbird. This is a typical-sized hummingbird, being a very small bird. It weighs , measures long and spans across the wings.

Distribution and habitat

Western rufous hummingbirds migrate through the

Rocky Mountains The Rocky Mountains, also known as the Rockies, are a major mountain range and the largest mountain system in North America. The Rocky Mountains stretch in great-circle distance, straight-line distance from the northernmost part of Western Can ...

and nearby lowlands from May to September to take advantage of the

wildflower A wildflower (or wild flower) is a flower that grows in the wild, rather than being intentionally seeded or planted. The term implies that the plant is neither a hybrid nor a selected cultivar that is any different from the native plant, eve ...

season. They may stay in one local region for the entire summer, in which case the migrants (like breeding birds) often aggressively take-over and defend feeding locations. Most individuals winter in wooded areas in the Mexican state of

Guerrero Guerrero, officially the Free and Sovereign State of Guerrero, is one of the 32 states that compose the administrative divisions of Mexico, 32 Federal Entities of Mexico. It is divided into Municipalities of Guerrero, 85 municipalities. The stat ...

, traveling over by an overland route from their nearest summer home – a prodigious journey for a bird weighing only . Adult male rufous hummingbirds tend to migrate slightly earlier than females or young. Since juveniles and females are essentially indistinguishable from Allen's hummingbird, unless confirmed by close inspection, eastern rufous migrants may be classified as "rufous/Allen's hummingbirds".

Behavior and ecology

Food and feeding

They feed on

nectar Nectar is a viscous, sugar-rich liquid produced by Plant, plants in glands called nectaries, either within the flowers with which it attracts pollination, pollinating animals, or by extrafloral nectaries, which provide a nutrient source to an ...

from flowers using a long extendable tongue or catch

insect Insects (from Latin ') are Hexapoda, hexapod invertebrates of the class (biology), class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body (Insect morphology#Head, head, ...

s on the wing. These birds require frequent feeding while active during the day and become torpid at night to conserve energy. Because of their small size, they are vulnerable to insect-eating birds and animals.

Hovering and sexual dimorphism

A study that used

digital imaging Digital imaging or digital image acquisition is the creation of a digital representation of the visual characteristics of an object, such as a physical scene or the interior structure of an object. The term is often assumed to imply or include ...

velocimetry to look at wing movements found that the rufous hummingbird supports its body weight during hovering primarily by wing downstrokes (75% of

lift Lift or LIFT may refer to: Physical devices * Elevator, or lift, a device used for raising and lowering people or goods ** Paternoster lift, a type of lift using a continuous chain of cars which do not stop ** Patient lift, or Hoyer lift, mobile ...

) rather than by upstrokes (25% of lift). When hovering during

fasting Fasting is the act of refraining from eating, and sometimes drinking. However, from a purely physiological context, "fasting" may refer to the metabolic status of a person who has not eaten overnight (before "breakfast"), or to the metabolic sta ...

, rufous hummingbirds

oxidize Redox ( , , reduction–oxidation or oxidation–reduction) is a type of chemical reaction in which the oxidation states of the reactants change. Oxidation is the loss of electrons or an increase in the oxidation state, while reduction is ...

fatty acids In chemistry, in particular in biochemistry, a fatty acid is a carboxylic acid with an aliphatic chain, which is either saturated or unsaturated. Most naturally occurring fatty acids have an unbranched chain of an even number of carbon atoms, ...

to support

metabolism Metabolism (, from ''metabolē'', "change") is the set of life-sustaining chemical reactions in organisms. The three main functions of metabolism are: the conversion of the energy in food to energy available to run cellular processes; the co ...

and

food energy Food energy is chemical energy that animals and humans derive from food to sustain their metabolism and muscular activity. Most animals derive most of their energy from aerobic respiration, namely combining the carbohydrates, fats, and protein ...

requirements, but can rapidly switch to

carbohydrate A carbohydrate () is a biomolecule composed of carbon (C), hydrogen (H), and oxygen (O) atoms. The typical hydrogen-to-oxygen atomic ratio is 2:1, analogous to that of water, and is represented by the empirical formula (where ''m'' and ''n'' ...

metabolism (within 40 minutes) after feeding on flower

. Both males and females are territorial; however, they defend different types of territories. The more aggressive males fight to defend areas with dense flowers, pushing females into areas with more sparsely populated flowers. Males generally have shorter wings than females, therefore their metabolic cost for hovering is higher. This allows males to beat their wings at high frequencies, giving them the ability to chase and attack other birds to defend their territory. The metabolic cost of short wings is compensated for by the fact that these males do not need to waste energy foraging for food, because their defended territory provides plenty of sustenance. Females on the other hand are not given access to the high concentration food sources, because the males fight them off. Therefore, females generally defend larger territories, where flowers are more sparsely populated, forcing them to fly farther between food sources. The metabolic cost of flying farther is compensated for with longer wings providing more efficient flight for females. The differences in wing length demonstrate a distinct sexual dimorphism, allowing each sex to best exploit resources in an area.

Breeding

Their primary breeding habitats are open areas,

mountain A mountain is an elevated portion of the Earth's crust, generally with steep sides that show significant exposed bedrock. Although definitions vary, a mountain may differ from a plateau in having a limited summit area, and is usually higher t ...

sides and forest edges in western

North America North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South Ameri ...

from southern

Alaska Alaska ( ) is a non-contiguous U.S. state on the northwest extremity of North America. Part of the Western United States region, it is one of the two non-contiguous U.S. states, alongside Hawaii. Alaska is also considered to be the north ...

through

British Columbia British Columbia is the westernmost Provinces and territories of Canada, province of Canada. Situated in the Pacific Northwest between the Pacific Ocean and the Rocky Mountains, the province has a diverse geography, with rugged landscapes that ...

and the

Pacific Northwest The Pacific Northwest (PNW; ) is a geographic region in Western North America bounded by its coastal waters of the Pacific Ocean to the west and, loosely, by the Rocky Mountains to the east. Though no official boundary exists, the most common ...

California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

, nesting further north (Alaska) than any other hummingbird. The female builds a

nest A nest is a structure built for certain animals to hold Egg (biology), eggs or young. Although nests are most closely associated with birds, members of all classes of vertebrates and some invertebrates construct nests. They may be composed of ...

in a protected location in a shrub or

conifer Conifers () are a group of conifer cone, cone-bearing Spermatophyte, seed plants, a subset of gymnosperms. Scientifically, they make up the phylum, division Pinophyta (), also known as Coniferophyta () or Coniferae. The division contains a sin ...

. Males are

promiscuous Promiscuity is the practice of engaging in sexual activity frequently with different partners or being indiscriminate in the choice of sexual partners. The term can carry a moral judgment. A common example of behavior viewed as promiscuous by man ...

, mating with several females.

Conservation status

In 2018, the rufous hummingbird was uplisted from

least concern A least-concern species is a species that has been evaluated and categorized by the International Union for Conservation of Nature (IUCN) as not being a focus of wildlife conservation because the specific species is still plentiful in the wil ...

near threatened A near-threatened species is a species which has been Conservation status, categorized as "Near Threatened" (NT) by the International Union for Conservation of Nature (IUCN) as that may be vulnerable to Endangered species, endangerment in the ne ...

on the

IUCN Red List The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is an inventory of the global conservation status and extinction risk of biological ...

, on the basis that due to its reliance on insect prey during the wintering season, it will be heavily affected by the global decline in insect populations due to

pesticide Pesticides are substances that are used to control pests. They include herbicides, insecticides, nematicides, fungicides, and many others (see table). The most common of these are herbicides, which account for approximately 50% of all p ...

s and intensified agriculture. Due to

climate change Present-day climate change includes both global warming—the ongoing increase in Global surface temperature, global average temperature—and its wider effects on Earth's climate system. Climate variability and change, Climate change in ...

, many flowers that the rufous hummingbird feeds on during the breeding season have started blooming two weeks prior to the birds' arrival to their breeding locations, which may lead to rufous hummingbirds arriving too late to feed on them.

Gallery

File:Rufous hummingbird attacking Anna's hummingbird.webm, Slow-motion video of rufous hummingbird attacking Anna's hummingbird at feeder. Video taken at 2000 fps, or about of real-time. File:Rufous hummingbird feeding in slow motion.webm, Rufous hummingbird feeding in slow motion at 2000 fps or of real-time.

References

External links

Rufous hummingbird Species Account - Cornell Lab of Ornithology
* * * {{Authority control rufous hummingbird Native birds of Alaska Native birds of Western Canada Native birds of the Northwestern United States Meso-American wintering birds rufous hummingbird rufous hummingbird