Sunbirds and spiderhunters make up the
family
Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...
Nectariniidae
Sunbirds and spiderhunters make up the family Nectariniidae of passerine birds. They are small, slender passerines from the Old World, usually with downward-curved bills. Many are brightly coloured, often with iridescent feathers, particularly i ...
of
passerine
A passerine () is any bird of the order Passeriformes (; from Latin 'sparrow' and '-shaped'), which includes more than half of all bird species. Sometimes known as perching birds, passerines are distinguished from other orders of birds by t ...
birds. They are small, slender passerines from the
Old World
The "Old World" is a term for Afro-Eurasia that originated in Europe , after Europeans became aware of the existence of the Americas. It is used to contrast the continents of Africa, Europe, and Asia, which were previously thought of by the ...
, usually with downward-curved bills. Many are brightly coloured, often with iridescent feathers, particularly in the males. Many species also have especially long tail feathers. Their range extends through most of Africa to the Middle East, South Asia, South-east Asia and southern China, to Indonesia, New Guinea and northern Australia. Species diversity is highest in equatorial regions.
There are 145 species in 16
genera
Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nomenclat ...
. Most sunbirds feed largely on
nectar
Nectar is a sugar-rich liquid produced by plants in glands called nectaries or nectarines, either within the flowers with which it attracts pollinating animals, or by extrafloral nectaries, which provide a nutrient source to animal mutualists ...
, but will also eat
insect
Insects (from Latin ') are pancrustacean hexapod invertebrates of the class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body ( head, thorax and abdomen), three pairs ...
s and
spider
Spiders ( order Araneae) are air-breathing arthropods that have eight legs, chelicerae with fangs generally able to inject venom, and spinnerets that extrude silk. They are the largest order of arachnids and rank seventh in total species ...
s, especially when feeding their young. Flowers that prevent access to their nectar because of their shape (for example, very long and narrow flowers) are simply punctured at the base near the nectaries, from which the birds sip the nectar.
Fruit
In botany, a fruit is the seed-bearing structure in flowering plants that is formed from the ovary after flowering.
Fruits are the means by which flowering plants (also known as angiosperms) disseminate their seeds. Edible fruits in particu ...
is also part of the diet of some species. Their
flight
Flight or flying is the process by which an object moves through a space without contacting any planetary surface, either within an atmosphere (i.e. air flight or aviation) or through the vacuum of outer space (i.e. spaceflight). This can be a ...
is fast and direct, thanks to their short wings.
The sunbirds have counterparts in two very distantly related groups: the
hummingbird
Hummingbirds are birds native to the Americas and comprise the biological family Trochilidae. With about 361 species and 113 genera, they occur from Alaska to Tierra del Fuego, but the vast majority of the species are found in the tropics aro ...
s of the Americas and the
honeyeater
The honeyeaters are a large and diverse family (biology), family, Meliphagidae, of small to medium-sized birds. The family includes the Epthianura, Australian chats, myzomelas, friarbirds, wattlebirds, Manorina, miners and melidectes. They are ...
s of Australia. The resemblances are due to
convergent evolution
Convergent evolution is the independent evolution of similar features in species of different periods or epochs in time. Convergent evolution creates analogous structures that have similar form or function but were not present in the last com ...
brought about by a similar nectar-feeding lifestyle. Some sunbird species can take nectar by hovering like a hummingbird, but they usually perch to feed.
Description
![Spectacled-spiderhunter](https://upload.wikimedia.org/wikipedia/commons/4/47/Spectacled-spiderhunter.jpg)
The family ranges in size from the 5-gram
black-bellied sunbird
The black-bellied sunbird (''Cinnyris nectarinioides'') is a species of bird in the family Nectariniidae.
It is found in Ethiopia, Kenya, Somalia, and Tanzania. At an average weight of around 5 grams, this is the smallest known species of sun ...
to the
spectacled spiderhunter
The spectacled spiderhunter (''Arachnothera flavigaster'') is a species of bird in the family Nectariniidae.
It is found in Brunei, Indonesia, Malaysia, Singapore, Thailand, and Vietnam.
Its natural habitats are subtropical or tropical moist lowl ...
, at about 45 grams. Like the hummingbirds, sunbirds are strongly
sexually dimorphic
Sexual dimorphism is the condition where the sexes of the same animal and/or plant species exhibit different morphological characteristics, particularly characteristics not directly involved in reproduction. The condition occurs in most ani ...
, with the males usually brilliantly plumaged in
iridescent
Iridescence (also known as goniochromism) is the phenomenon of certain surfaces that appear to gradually change color as the angle of view or the angle of illumination changes. Examples of iridescence include soap bubbles, feathers, butterfl ...
colours.
In addition to this the tails of many species are longer in the males, and overall the males are larger. Sunbirds have long thin down-curved bills and brush-tipped tubular tongues, both adaptations to their nectar feeding. The
spiderhunter
The spiderhunters are birds of the genus ''Arachnothera'', part of the sunbird family Nectariniidae. The genus contains thirteen species found in the forests of south and southeastern Asia. They are large representatives of the sunbird family, wi ...
s, of the genus ''Arachnothera'', are distinct in appearance from the other members of the family. They are typically larger than the other sunbirds, with drab brown plumage that is the same for both sexes, and long, down-curved beaks.
In metabolic behaviour similar to that of Andes hummingbirds, species of sunbirds that live at high altitudes or latitudes will enter
torpor
Torpor is a state of decreased physiological activity in an animal, usually marked by a reduced body temperature and metabolic rate. Torpor enables animals to survive periods of reduced food availability. The term "torpor" can refer to the time ...
while roosting at night, lowering their body temperature and entering a state of low activity and responsiveness.
The moulting regimes of sunbirds are complex, being different in different species. Many species have no eclipse plumage, but do have juvenile plumage. Some species do show duller plumage in the off-season. In the dry months of June−August, male copper sunbirds and variable sunbirds lose much of their metallic sheen. In some instances different populations of the same species can display variation in different molting regimes.
Distribution and habitat
Sunbirds are a tropical
Old World
The "Old World" is a term for Afro-Eurasia that originated in Europe , after Europeans became aware of the existence of the Americas. It is used to contrast the continents of Africa, Europe, and Asia, which were previously thought of by the ...
family, with representatives in
Africa
Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 6% of Earth's total surface area ...
,
Asia
Asia (, ) is one of the world's most notable geographical regions, which is either considered a continent in its own right or a subcontinent of Eurasia, which shares the continental landmass of Afro-Eurasia with Africa. Asia covers an area ...
and
Australasia
Australasia is a region that comprises Australia, New Zealand and some neighbouring islands in the Pacific Ocean. The term is used in a number of different contexts, including geopolitically, physiogeographically, philologically, and ecologica ...
. In Africa they are found mostly in sub-Saharan
Africa
Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 6% of Earth's total surface area ...
and
Madagascar
Madagascar (; mg, Madagasikara, ), officially the Republic of Madagascar ( mg, Repoblikan'i Madagasikara, links=no, ; french: République de Madagascar), is an island country in the Indian Ocean, approximately off the coast of East Africa ...
but are also distributed in
Egypt
Egypt ( ar, مصر , ), officially the Arab Republic of Egypt, is a transcontinental country spanning the northeast corner of Africa and southwest corner of Asia via a land bridge formed by the Sinai Peninsula. It is bordered by the Mediter ...
. In Asia the group occurs along the coasts of the
Red Sea
The Red Sea ( ar, البحر الأحمر - بحر القلزم, translit=Modern: al-Baḥr al-ʾAḥmar, Medieval: Baḥr al-Qulzum; or ; Coptic: ⲫⲓⲟⲙ ⲛ̀ϩⲁϩ ''Phiom Enhah'' or ⲫⲓⲟⲙ ⲛ̀ϣⲁⲣⲓ ''Phiom ǹšari''; T ...
as far north as
Israel
Israel (; he, יִשְׂרָאֵל, ; ar, إِسْرَائِيل, ), officially the State of Israel ( he, מְדִינַת יִשְׂרָאֵל, label=none, translit=Medīnat Yīsrāʾēl; ), is a country in Western Asia. It is situated ...
, and along the Mediterranean as far north as
Beirut
Beirut, french: Beyrouth is the capital and largest city of Lebanon. , Greater Beirut has a population of 2.5 million, which makes it the third-largest city in the Levant region. The city is situated on a peninsula at the midpoint o ...
, with a gap in their distribution across inland Syria and Iraq, and resuming in
Iran
Iran, officially the Islamic Republic of Iran, and also called Persia, is a country located in Western Asia. It is bordered by Iraq and Turkey to the west, by Azerbaijan and Armenia to the northwest, by the Caspian Sea and Turkmeni ...
, from where the group occurs continuously as far as southern
China
China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's most populous country, with a population exceeding 1.4 billion, slightly ahead of India. China spans the equivalent of five time zones and ...
and
Indonesia
Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania between the Indian and Pacific oceans. It consists of over 17,000 islands, including Sumatra, Java, Sulawesi, and parts of Borneo and New Guine ...
. In Australasia the family occurs in
New Guinea
New Guinea (; Hiri Motu
Hiri Motu, also known as Police Motu, Pidgin Motu, or just Hiri, is a language of Papua New Guinea, which is spoken in surrounding areas of Port Moresby (Capital of Papua New Guinea).
It is a simplified version of ...
, north eastern
Australia
Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...
and the
Solomon Islands
Solomon Islands is an island country consisting of six major islands and over 900 smaller islands in Oceania, to the east of Papua New Guinea and north-west of Vanuatu. It has a land area of , and a population of approx. 700,000. Its capita ...
. They are generally not found on oceanic islands, with the exception of the
Seychelles
Seychelles (, ; ), officially the Republic of Seychelles (french: link=no, République des Seychelles; Creole: ''La Repiblik Sesel''), is an archipelagic state consisting of 115 islands in the Indian Ocean. Its capital and largest city, V ...
. The greatest variety of species is found in Africa, where the group probably arose. Most species are sedentary or short-distance
seasonal migrants. Sunbirds occur over the entire family's range, whereas the spiderhunters are restricted to
Asia
Asia (, ) is one of the world's most notable geographical regions, which is either considered a continent in its own right or a subcontinent of Eurasia, which shares the continental landmass of Afro-Eurasia with Africa. Asia covers an area ...
.
The sunbirds and spiderhunters occupy a wide range of habitats, with a majority of species being found in primary rainforest, but other habitats used by the family including disturbed secondary forest, open woodland, open scrub and savannah, coastal scrub and alpine forest. Some species have readily adapted to human modified landscapes such as plantations, gardens and agricultural land. Many species are able to occupy a wide range of habitats from sea level to 4900 m.
Behaviour and ecology
Sunbird are active
diurnal birds that generally occur in pairs or occasionally in small family groups. A few species occasionally gather in larger groups, and sunbird will join with other birds to
mob
Mob or MOB may refer to:
Behavioral phenomena
* Crowd
* Smart mob, a temporary self-structuring social organization, coordinated through telecommunication
Crime and law enforcement
* American Mafia, also known as the Mob
* Irish Mob, a US crimin ...
potential predators, although sunbirds will also aggressively target other species, even if they are not predators, when defending their
territories
A territory is an area of land, sea, or space, particularly belonging or connected to a country, person, or animal.
In international politics, a territory is usually either the total area from which a state may extract power resources or an ...
.
Breeding
![Nectarinia dussumieri feeding young](https://upload.wikimedia.org/wikipedia/commons/1/1f/Nectarinia_dussumieri_feeding_young.jpg)
Sunbirds that breed outside of the equatorial regions are mostly seasonal breeders, with the majority of them breeding in the
wet season
The wet season (sometimes called the Rainy season) is the time of year when most of a region's average annual rainfall occurs. It is the time of year where the majority of a country's or region's annual precipitation occurs. Generally, the sea ...
. This timing reflects the increased availability of insect prey for the growing young. Where species, like the
buff-throated sunbird
The buff-throated sunbird (''Chalcomitra adelberti'') is a species of bird in the family Nectariniidae. It is found in Benin, Cameroon, Ivory Coast, Ghana, Guinea, Guinea-Bissau, Liberia, Nigeria, Sierra Leone, and Togo.
References
Chal ...
, breed in the dry season, it is thought to be associated with the flowering of favoured food plants. Species of sunbird in the equatorial areas breed throughout the year. They are generally
monogamous
Monogamy ( ) is a form of Dyad (sociology), dyadic Intimate relationship, relationship in which an individual has only one Significant other, partner during their lifetime. Alternately, only one partner at any one time (Monogamy#Serial monogamy, ...
and often territorial, although a few species of sunbirds have
lekking
A lek is an aggregation of male animals gathered to engage in competitive displays and courtship rituals, known as lekking, to entice visiting females which are surveying prospective partners with which to mate. A lek can also indicate an avail ...
behaviour.
The
nests
A nest is a structure built for certain animals to hold 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 organic materi ...
of sunbirds are generally purse-shaped, enclosed, suspended from thin branches with generous use of spiderweb. The nests of the spiderhunters are different, both from the sunbirds and in some cases from each other. Some, like the
little spiderhunter
The little spiderhunter (''Arachnothera longirostra'') is a species of long-billed nectar-feeding bird in the family Nectariniidae found in the moist forests of South and Southeast Asia. Unlike typical sunbirds, males and females are very similar ...
, are small woven cups attached to the underside of large leaves; that of the
yellow-eared spiderhunter
The yellow-eared spiderhunter (''Arachnothera chrysogenys'') is a species of bird in the family Nectariniidae.
It is found in Brunei, Indonesia, Malaysia, Myanmar, Singapore, Thailand, and Vietnam.
Its natural habitats are subtropical or tropical ...
is similarly attached but is a long tube. The nests of spiderhunters are inconspicuous, in contrast to those of the other sunbirds which are more visible. In most species the female alone constructs the nest. Up to four eggs are laid. The female builds the nest and incubates the eggs alone, although the male assists in rearing the nestlings.
In the spiderhunters both sexes help to incubate the eggs.
[ The nests of sunbirds and spiderhunters are often targeted by ]brood parasite
Brood parasites are animals that rely on others to raise their young. The strategy appears among birds, insects and fish. The brood parasite manipulates a host, either of the same or of another species, to raise its young as if it were its own ...
s such as cuckoo
Cuckoos are birds in the Cuculidae family, the sole taxon in the order Cuculiformes . The cuckoo family includes the common or European cuckoo, roadrunners, koels, malkohas, couas, coucals and anis. The coucals and anis are sometimes separ ...
s and honeyguide
Honeyguides (family Indicatoridae) are near passerine birds in the order Piciformes. They are also known as indicator birds, or honey birds, although the latter term is also used more narrowly to refer to species of the genus '' Prodotiscus''. Th ...
s.
Pollination
As nectar is a primary food source for sunbirds, they are important pollinator
A pollinator is an animal that moves pollen from the male anther of a flower to the female stigma of a flower. This helps to bring about fertilization of the ovules in the flower by the male gametes from the pollen grains.
Insects are the maj ...
s in African ecosystems. Sunbird-pollinated flowers are typically long, tubular, and red-to-orange in colour, showing convergent evolution with many hummingbird
Hummingbirds are birds native to the Americas and comprise the biological family Trochilidae. With about 361 species and 113 genera, they occur from Alaska to Tierra del Fuego, but the vast majority of the species are found in the tropics aro ...
-pollinated flowers in the Americas. A key difference is that sunbirds cannot hover, so sunbird-pollinated flowers and inflorescence
An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Morphologically, it is the modified part of the shoot of seed plants where flowers are formed o ...
s are typically sturdier than hummingbird-pollinated flowers, with an appropriate landing spot from which the bird can feed. Sunbirds are critical pollinators for many iconic African plants, including protea
''Protea'' () is a genus of South African flowering plants, also called sugarbushes (Afrikaans: ''suikerbos'').
Etymology
The genus ''Protea'' was named in 1735 by Carl Linnaeus, possibly after the Greek god Proteus, who could change his form a ...
s, aloe
''Aloe'' (; also written ''Aloë'') is a genus containing over 650 species of flowering succulent plants.WFO (2022): Aloe L. Published on the Internet;http://www.worldfloraonline.org/taxon/wfo-4000001341. Accessed on: 06 Nov 2022 The most wid ...
s, ''Erica
Erica or ERICA may refer to:
* Erica (given name)
* ''Erica'' (plant), a flowering plant genus
* Erica (chatbot), a service of Bank of America
* ''Erica'' (video game), a 2019 FMV video game
* ''Erica'' (spider), a jumping spider genus
* Eric ...
'', ''Erythrina
''Erythrina'' is a genus of plants in the pea family, Fabaceae. It contains about 130 species, which are distributed in tropical and subtropical regions worldwide. They are trees, with the larger species growing up to in height. The generic na ...
'' coral trees, and bird-of-paradise
The birds-of-paradise are members of the family Paradisaeidae of the order Passeriformes. The majority of species are found in eastern Indonesia, Papua New Guinea and eastern Australia. The family has 44 species in 17 genera. The members of thi ...
flowers. Specialization on sunbirds vs other pollinators is thought to have contributed to plant speciation
Speciation is the evolutionary process by which populations evolve to become distinct species. The biologist Orator F. Cook coined the term in 1906 for cladogenesis, the splitting of lineages, as opposed to anagenesis, phyletic evolution within ...
, including the exceptionally high flora diversity in southern Africa.
Relationship with humans
Overall the family has fared better than many others, with only seven species considered to be threatened
Threatened species are any species (including animals, plants and fungi) which are vulnerable to endangerment in the near future. Species that are threatened are sometimes characterised by the population dynamics measure of ''critical depensat ...
with extinction
Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...
. Most species are fairly resistant to changes in habitat, and while attractive the family is not sought after by the cagebird trade, as they have what is considered an unpleasant song and are tricky to keep alive. Sunbirds are considered attractive birds and readily enter gardens where flowering plants are planted to attract them. There are a few negative interactions, for example the scarlet-chested sunbird
The scarlet-chested sunbird (''Chalcomitra senegalensis'') is a species of bird in the family Nectariniidae.
Range
It is found in Angola, Benin, Botswana, Burkina Faso, Burundi, Cameroon, Central African Republic, Chad, Democratic Republic of th ...
is considered a pest in cocoa plantations as it spreads parasitic mistletoe
Mistletoe is the common name for obligate hemiparasitic plants in the order Santalales. They are attached to their host tree or shrub by a structure called the haustorium, through which they extract water and nutrients from the host plant.
...
s.
List of genera
The family contains 146 species divided into 16 genera: For more detail, see list of sunbird species
Nectariniidae is a Family (biology), family of passerine birds in the superfamily Passeroidea, comprising the sunbirds and spiderhunters. Members of Nectariniidae are also known as nectariniids. Their range extends from the Afrotropics north to ...
.
References
External links
Sunbird videos
on the Internet Bird Collection
{{Authority control
Nectariniidae
Taxa named by Nicholas Aylward Vigors