Gurney's sugarbird (''Promerops gurneyi'') is a medium-sized passerine

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

to the mid- and high-altitude grassland velds in southern Africa. It belongs to the family Promeropidae, which contains one genus, ''

Promerops The sugarbirds are a small family (biology), genus, ''Promerops'', and family, Promeropidae, of passerine birds, Endemism, restricted to southern Africa. In general appearance and habits, they resemble large, long-tailed sunbirds or some of the ...

'', and two species. Gurney's sugarbird feeds on nectar from ''

Protea ''Protea'' () is a genus of South African flowering plants, also called sugarbushes (Afrikaans: ''suikerbos''). It is the type genus of the Proteaceae family. About 92% of the species occur only in the Cape Floristic Region, a narrow belt of mo ...

'' bushes as well as on small insects. This bird is characterized by its long, graduated tail and decurved beak. The common name and Latin binomial commemorate the British banker and amateur ornithologist

John Henry Gurney John Henry Gurney (4 July 1819 – 20 April 1890) was an English banker, amateur ornithologist, and Liberal Party politician of the Gurney family. Life Gurney was the only son of Joseph John Gurney of Earlham Hall, Norwich, Norfolk. At the ag ...

(1819-1890).

Description

Gurney's sugarbird has a long, decurved bill characteristic of nectarivores. It has a chestnut-coloured forehead, along with a faint white eyestripe and white mustachial stripe. A white throat stands out against the russet breast. This species of sugarbird has a dark grey back, and a conspicuous bright yellow rump makes this bird easy to spot. The tail is long and graduated, ranging from 11 to 19.3 cm in length. This species measures between 23 and 29 cm in total, and body mass ranges from 30 to 46.5 g in males and 23 to 43 g in females. Females are smaller than males, with shorter bills and tail feathers. Males also have triangular-shaped bulge on the sixth

primary feather Flight feathers (''Pennae volatus'') are the long, stiff, asymmetrically shaped, but symmetrically paired pennaceous feathers on the wings or tail of a bird; those on the wings are called remiges (), singular remex (), while those on the tai ...

, used in mating displays. Immature individuals are duller than adults and have a greenish tinge to both their breast and yellow rump. Further, their

secondary feathers Flight feathers (''Pennae volatus'') are the long, stiff, asymmetrically shaped, but symmetrically paired pennaceous feathers on the Bird wing, wings or tail of a bird; those on the wings are called remiges (), singular remex (), while those ...

are edged with a brownish colour. The two

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 ...

of Gurney's surgarbird have minor differences in their appearance. ''P. g. gurneyi'' individuals fit the above description. Meanwhile, ''P. g. ardens'' individuals tend to be darker, with a greener rump and a richer chestnut breast than their counterpart subspecies. Gurney's sugarbirds moult their

flight feathers Flight feathers (''Pennae volatus'') are the long, stiff, asymmetrically shaped, but symmetrically paired pennaceous feathers on the wings or tail of a bird; those on the wings are called remiges (), singular remex (), while those on the tai ...

(primary and secondary feathers) during the breeding season. Tail feathers, however, moult throughout the year continuously. This is because the long feathers are easily damaged and must be replaced quickly due to their important role in mating displays.

Taxonomy

''Promerops gurneyi'' is one of two species within the genus ''Promerops'' and the monotypic family Promeropidae. Gurney's sugarbird has a single sister species, the

Cape sugarbird The Cape sugarbird (''Promerops cafer'') is one of the eight bird species endemic to the Fynbos biome of the Western Cape and Eastern Cape provinces of South Africa. Taxonomy The Cape sugarbird was formally described in 1758 by the Swedish natu ...

(''Promerops cafer''). Its taxonomic ranking baffled scientists for many years. This family has been grouped in with the

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 ...

(sunbird) family, due to their physical resemblances and shared geographic origins, as both sunbirds and sugarbirds evolved in Africa. Promeropidae was also once classified in the Australian

Meliphagidae 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 m ...

(honeyeaters) family, because of their shared and unique tongue structure, behaviour, and nest-building. There was no evidence of common lineage, however, and similarities appear to be from

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 comm ...

. Analysis of protein structure from egg whites and red blood cells showed that sugarbirds are derived specialists of African

starlings Starlings are small to medium-sized passerine (perching) birds known for the often dark, glossy iridescent sheen of their plumage; their complex vocalizations including mimicking; and their distinctive, often elaborate swarming behavior, known ...

. Genetically, the ''Promerops'' genus is most closely related to the ''Cinnyricinclus'' and ''

Onychognathus ''Onychognathus'' is a genus of starlings native to the Afrotropical realm. All the species are quite similar, and characterised by rufous primary wing feathers, very obvious in flight. The males are typically mainly glossy black, and the females ...

'' genera. It is today classified as its own family. Presently 2 subspecies of Gurney's sugarbird are recognized, ''Promerops gurneyi gurneyi'' and ''Promerops gurneyi ardens''. ''P. g. ardens'' was recognized in 1952 and arose from an isolated population of Gurney's sugarbird located in high-elevation areas of Eastern Zimbabwe and the adjacent

Mozambique Mozambique, officially the Republic of Mozambique, is a country located in Southeast Africa bordered by the Indian Ocean to the east, Tanzania to the north, Malawi and Zambia to the northwest, Zimbabwe to the west, and Eswatini and South Afr ...

. The ranges of the two subspecies do not overlap, and they occupy different types of habitats.

Distribution and habitat

Gurney's sugarbird is a species

Southern Africa Southern Africa is the southernmost region of Africa. No definition is agreed upon, but some groupings include the United Nations geoscheme for Africa, United Nations geoscheme, the intergovernmental Southern African Development Community, and ...

. The distribution is fragmented, and these birds are mainly found in elevated regions in north-eastern Mountain Sourveld and north-eastern Sandy

Highveld The Highveld (Afrikaans: ''Hoëveld,'' , ) is the portion of the South African inland plateau which has an altitude above roughly , but below , thus excluding the Lesotho mountain regions to the south-east of the Highveld. It is home to some of t ...

in the

Transvaal Transvaal is a historical geographic term associated with land north of (''i.e.'', beyond) the Vaal River in South Africa. A number of states and administrative divisions have carried the name ''Transvaal''. * South African Republic (1856–1902; ...

and Natal regions. They are also found in

Highland Highlands or uplands are areas of high elevation such as a mountainous region, elevated mountainous plateau or high hills. Generally, ''upland'' refers to a range of hills, typically from up to , while ''highland'' is usually reserved for range ...

and Dohne Sourvelds of Natal and into the

Eastern Cape The Eastern Cape ( ; ) is one of the nine provinces of South Africa. Its capital is Bhisho, and its largest city is Gqeberha (Port Elizabeth). Due to its climate and nineteenth-century towns, it is a common location for tourists. It is also kno ...

and

Limpopo Limpopo () is the northernmost Provinces of South Africa, province of South Africa. It is named after the Limpopo River, which forms the province's western and northern borders. The term Limpopo is derived from Rivombo (Livombo/Lebombo), a ...

provinces. An isolated population of ''P. g. ardens'' is located in the highlands of Eastern Zimbabwe and adjacent

. Gurney's sugarbirds are short-distance altitudinal migrants and leave their breeding grounds once the flowering season is over. The preferred habitats is shrubland velds of

, dominated by sugarbush (''

'') species of flowering plants. Gurney's sugarbird distribution overlaps silver sugarbush (''

Protea roupelliae ''Protea roupelliae'' is a species of ''Protea'' in the large family Proteaceae, and was named to commemorate Arabella Elizabeth Roupell (1817–1914) who spent two years in Cape Town and painted local flowers for her own pleasure. This specie ...

)'', white protea (''P. subvestita''), and common sugarbush ('' P. afra)''. Because this species is only associated to ''

'' shrubs, it is very vulnerable to habitat loss and displacement due to fires. The distribution of these birds is restrained by their very specialized diet of sugarbush species' nectar. These birds also feed on nectar from ''

Aloe ''Aloe'' (; also written ''Aloë'') is a genus containing over 650 species of flowering plant, flowering succulent plant, succulent plants.WFO (2022): Aloe L. Published on the Internet;http://www.worldfloraonline.org/taxon/wfo-4000001341. Acc ...

'' gardens in suburban areas. ''P. g. ardens'' evolved in an area that lacks silver sugarbush, and it relies on miombo trees (''

Brachystegia ''Brachystegia'' is a genus of tree of the subfamily Detarioideae that is native to tropical Africa. Trees of the genus are commonly known as miombo, and are dominant in the miombo woodlands of central and southern tropical Africa. The Zambezia ...

'' genus) and African protea ('' P. gageudi)'', Nyanaga protea ('' P. dracomontana''), ''beard protea (''P. crintita'')'', and common sugarbush ('' P. afra'') species as food resources instead. ''P. g. ardens'' lives in riparian woods, on dry slopes with many flowering shrubs such as sugarbush (''

)'', bird of paradise flowers (''

Strelitzia ''Strelitzia'' is a genus of five species of perennial plants, native to South Africa. It belongs to the plant family Strelitziaceae. A common name of the genus is bird of paradise flower/plant, because of a resemblance of its flowers to bird ...

)'', and coral trees (''

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. These species ...

)''.

Behaviour

Vocalizations

The song for this species consists of three or four ascending notes, with the final note repeated several times. A "song-spell", songs repeated for an extended period of time, can last up to four minutes. Multiple song-spells strung together and separated by short pauses are called full song periods, and these can last for 20 minutes. Gurney's sugarbird calls are short, and characterized by a single note, often described as a "chit" sound. The call is more low-pitched than the song, and can be compounded into a "chit-chit-chit" sequence. The call is mostly used when approaching the nest, or as a indicator of well-being once a partner returns to the nest with food, for example. When defending the nest or territory from other birds, Gurney's sugarbird will make a "cloth-ripping" sound.

Diet

Gurney's sugarbirds are specialized nectarivores and

insectivores A robber fly eating a hoverfly An insectivore is a carnivorous animal or plant which eats insects. An alternative term is entomophage, which can also refer to the human practice of eating insects. The first vertebrate insectivores wer ...

feeding on ''

'' species, mainly ''

,'' as well as ''

Protea afra ''Protea afra'' (sometimes called the common protea), native to Africa, inhabiting from South Africa to Kenya, is a small tree or shrub which occurs in subtropical open or wooded grassland, usually on rocky ridges. Its leaves are leathery and ha ...

'' and ''

'' in suburban areas. The long, decurved bill is well-adapted to siphon nectar from ''

'' flower heads. These birds forage for insects and nectar within their defended territory. Insects are usually found hiding within the ''

'' flowers, or caught mid-flight. Main prey orders include

Hymenoptera Hymenoptera is a large order of insects, comprising the sawflies, wasps, bees, and ants. Over 150,000 living species of Hymenoptera have been described, in addition to over 2,000 extinct ones. Many of the species are parasitic. Females typi ...

(

wasps A wasp is any insect of the narrow-waisted suborder Apocrita of the order Hymenoptera which is neither a bee nor an ant; this excludes the broad-waisted sawflies (Symphyta), which look somewhat like wasps, but are in a separate suborder. Th ...

bees Bees are winged insects closely related to wasps and ants, known for their roles in pollination and, in the case of the best-known bee species, the western honey bee, for producing honey. Bees are a monophyletic lineage within the superfamil ...

sawflies Sawflies are wasp-like insects that are in the suborder Symphyta within the order Hymenoptera, alongside ants, bees, and wasps. The common name comes from the saw-like appearance of the ovipositor, which the females use to cut into the plant ...

and

ants Ants are eusocial insects of the family Formicidae and, along with the related wasps and bees, belong to the order Hymenoptera. Ants evolved from vespoid wasp ancestors in the Cretaceous period. More than 13,800 of an estimated total of ...

Coleoptera Beetles are insects that form the Taxonomic rank, order Coleoptera (), in the superorder Holometabola. Their front pair of wings are hardened into wing-cases, elytra, distinguishing them from most other insects. The Coleoptera, with about 40 ...

(beetles), and

Hemiptera Hemiptera (; ) is an order of insects, commonly called true bugs, comprising more than 80,000 species within groups such as the cicadas, aphids, planthoppers, leafhoppers, assassin bugs, bed bugs, and shield bugs. They range in size from ...

(true bugs). Adults tend to feed mainly on nectar, and during the breeding season small insects are the main prey items fed to chicks.

Reproduction

Gurney's sugarbird is a socially

monogamous Monogamy ( ) is a relationship of two individuals in which they form a mutual and exclusive intimate partnership. Having only one partner at any one time, whether for life or serial monogamy, contrasts with various forms of non-monogamy (e.g. ...

species, meaning that pairs remain together through the breeding season. This season lasts from September, when pairing and nest-building take place, until late February, when the fledglings leave their parents' territory. Females chose their mate based on morphological features (physical attributes) and display flights, which consist of flicking their long tail and the wing-'clacking' of the triangular bulge on their sixth primary feather. Longer tails and larger feather bulges for wing-'clacking' have been associated with greater mating success in males. Display flights also take place when the males chase away encroaching individuals, usually male, from their territory. Reproductive success in Gurney's sugarbird is highly dependent upon available resources, such as abundant nectar and insects. Males will typically defend these resources, while the females build the nest, incubate the eggs, and feed the nestlings.

Clutch size A clutch of eggs is the group of eggs produced by birds, amphibians, or reptiles, often at a single time, particularly those laid in a nest. In birds, destruction of a clutch by predators (or removal by humans, for example the California condor b ...

is small (usually 1-2 eggs) and is associated to this species' longer life span (up to seven years, maximum recorded longevity of 13 years). Individuals usually reach sexual maturity in their second or third year of life, and therefore typically survive for an average of five breeding seasons during their lifetime. Incubation lasts 16-17 days and brooding (keeping the chicks warm after hatching) between 19 and 23 days. Both parents participate in the feeding of the nestlings, usually bringing back small winged insects and beetles. Chicks are reliant on their parents for food for the first month of their life.

Gallery

File:Gurney's_Sugarbird,_Promerops_gurneyi_at_Marakele_National_Park.jpg, Gurney's sugarbird, at Marakele National Park File:Gurney's_Sugarbird,_Promerops_gurneyi_at_Marakele_National_Park_(14123201404).jpg, Gurney's sugarbird, at Marakele National Park

References

External links

Gurney's sugarbird - Species text in The Atlas of Southern African Birds.

Gurney's sugarbird vocalizations

Gurney's sugarbird - Bird Life International
{{Taxonbar, from=Q945676

Gurney's sugarbird Gurney's sugarbird (''Promerops gurneyi'') is a medium-sized passerine Endemism, endemic to the mid- and high-altitude grassland Veld, velds in southern Africa. It belongs to the family Sugarbird, Promeropidae, which contains one genus, ''Promero ...

Birds of Southern Africa

Taxonomy articles created by Polbot