Western cattle egret

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Western cattle egret
Cattle egret (Bubulcus ibis) summer plumage Cyprus.jpg
Summer plumage, Cyprus
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Pelecaniformes
Family: Ardeidae
Genus: Ardea
Species:
A. ibis
Binomial name
Ardea ibis
Linnaeus, 1758
Synonyms

Ardeola ibis(Linnaeus, 1758)
Egretta ibis(Linnaeus, 1758)
Lepterodatis ibis(Linnaeus, 1758)

Contents

Summer plumage, Cyprus Cattle egret (Bubulcus ibis) summer plumage head Cyprus.jpg
Summer plumage, Cyprus

The western cattle egret (Ardea ibis) is a species of heron (family Ardeidae) found in the tropics, subtropics and warm temperate zones. Formerly, most taxonomic authorities lumped this species and the eastern cattle egret together (called the cattle egret), but the two cattle egrets are now treated as separate species. Despite the similarities in plumage to the egrets of the genus Egretta , it is more closely related to the herons of Ardea . Originally native to parts of Asia, Africa and Europe, it has undergone a rapid expansion in its distribution and successfully colonised much of the rest of the world in the last century.

It is a white bird adorned with buff plumes in the breeding season. It nests in colonies, usually near bodies of water and often with other wading birds. The nest is a platform of sticks in trees or shrubs. Western cattle egrets exploit drier and open habitats more than other heron species. Their feeding habitats include seasonally inundated grasslands, pastures, farmlands, wetlands and rice paddies. They often accompany cattle or other large mammals, catching insect and small vertebrate prey disturbed by these animals. Some populations of the cattle egret are migratory and others show post-breeding dispersal.

The adult cattle egret has few predators, but birds or mammals may raid its nests, and chicks may be lost to starvation, calcium deficiency or disturbance from other large birds. This species maintains a special relationship with cattle, which extends to other large grazing mammals; wider human farming is believed to be a major cause of their suddenly expanded range. The cattle egret removes ticks and flies from cattle and consumes them. This benefits both species, but it has been implicated in the spread of tick-borne animal diseases.

Taxonomy

Breeding adult with neck retracted Cattle Egret Retracted Neck.jpg
Breeding adult with neck retracted

The cattle egret was first described in 1758 by Linnaeus in his Systema naturae as Ardea ibis, [1] but was moved to the genus Bubulcus by Charles Lucien Bonaparte in 1855. [2] It was moved back to the genus Ardea based on the results of a molecular phylogenetic study published in 2023 that found the cattle egrets were embedded with members of the genus Ardea. [3] [4] The genus name Ardea is the Latin word for a "heron". [5] Ibis is a Latin and Greek word which originally referred to another white wading bird, the sacred ibis, [6] but was applied to this species in error. [7]

Despite superficial similarities in appearance, the cattle egret is more closely related to the genus Ardea , which comprises the great or typical herons and the great egret (A. alba), than to the majority of species termed egrets in the genus Egretta . [8] Rare cases of hybridization with little blue herons Egretta caerulea, little egrets Egretta garzetta and snowy egrets Egretta thula have been recorded. [9]

Description

The cattle egret is a stocky heron with an 88–96 cm (35–38 in) wingspan; it is 46–56 cm (18–22 in) long and weighs 270–512 g (9.5–18.1 oz). [10] It has a relatively short thick neck, a sturdy bill, and a hunched posture. The non-breeding adult has mainly white plumage, a yellow bill and greyish-yellow legs. During the breeding season, adults of the nominate western subspecies develop orange-buff plumes on the back, breast and crown, and the bill, legs and irises become bright red for a brief period prior to pairing. [11] The sexes are similar, but the male is marginally larger and has slightly longer breeding plumes than the female; juvenile birds lack coloured plumes and have a black bill. [10] [12]

The positioning of the egret's eyes allows for binocular vision during feeding, [13] and physiological studies suggest that the species may be capable of crepuscular or nocturnal activity. [14] Adapted to foraging on land, they have lost the ability possessed by their wetland relatives to accurately correct for light refraction by water. [15]

This species gives a quiet, throaty rick-rack call at the breeding colony, but is otherwise largely silent. [16]

Distribution and habitat

Range expansion in the Americas (click to magnify) Cattle egret spread.svg
Range expansion in the Americas (click to magnify)

The cattle egret has undergone one of the most rapid and wide reaching natural expansions of any bird species. [16] It was originally native to parts of Southern Spain and Portugal, tropical and subtropical Africa and humid tropical and western Asia. In the end of the 19th century it began expanding its range into southern Africa, first breeding in the Cape Province in 1908. [17] Cattle egrets were first sighted in the Americas on the boundary of Guiana and Suriname in 1877, having apparently flown across the Atlantic Ocean. [18] [10] It was not until the 1930s that the species is thought to have become established in that area. [19]

The species first arrived in North America in 1941 (these early sightings were originally dismissed as escapees), bred in Florida in 1953, and spread rapidly, breeding for the first time in Canada in 1962. [17] It is now commonly seen as far west as California. It was first recorded breeding in Cuba in 1957, in Costa Rica in 1958, and in Mexico in 1963, although it was probably established before that. [19] In Europe, the species had historically declined in Spain and Portugal, but in the latter part of the 20th century it expanded back through the Iberian Peninsula, and then began to colonise other parts of Europe; southern France in 1958, northern France in 1981 and Italy in 1985. [17] Breeding in the United Kingdom was recorded for the first time in 2008 only a year after an influx seen in the previous year. [20] [21] In 2008, cattle egrets were also reported as having moved into Ireland for the first time. [22]

The massive and rapid expansion of the cattle egret's range is due to its relationship with humans and their domesticated animals. Originally adapted to a commensal relationship with large grazing and browsing animals, it was easily able to switch to domesticated cattle and horses. As the keeping of livestock spread throughout the world, the cattle egret was able to occupy otherwise empty niches. [23] Many populations of cattle egrets are highly migratory and dispersive, [16] and this has helped the species' range expansion. The species has been seen as a vagrant in various sub-Antarctic islands, including South Georgia, Marion Island, the South Sandwich Islands and the South Orkney Islands. [24] A small flock of eight birds was also seen in Fiji in 2008. [25]

In addition to the natural expansion of its range, cattle egrets have been deliberately introduced into a few areas. The species was introduced to Hawaii in 1959. Successful releases were also made in the Seychelles and Rodrigues, but attempts to introduce the species to Mauritius failed. Numerous birds were also released by Whipsnade Zoo in England, but the species was never established. [26]

Although the cattle egret sometimes feeds in shallow water, unlike most herons it is typically found in fields and dry grassy habitats, reflecting its greater dietary reliance on terrestrial insects rather than aquatic prey. [27]

Migration and movements

Flying in Dallas with a twig in its beak for its nest Bubulcus ibis -Dallas, Texas, USA -flying-8.jpg
Flying in Dallas with a twig in its beak for its nest

Some populations of cattle egrets are migratory, others are dispersive, and distinguishing between the two can be difficult for this species. [16] In many areas populations can be both sedentary and migratory. In the northern hemisphere, migration is from cooler climes to warmer areas. Migration in western Africa is in response to rainfall, and in South America migrating birds travel south of their breeding range in the non-breeding season. [16]

Young birds are known to disperse up to 5,000 km (3,100 mi) from their breeding area. Flocks may fly vast distances and have been seen over seas and oceans including in the middle of the Atlantic. [28]

A flock in a tree at Jacutinga, Minas Gerais state, Brazil Bubulcus ibis - Cattle egret (flock).jpg
A flock in a tree at Jacutinga, Minas Gerais state, Brazil

Status

This species has a large range, with an estimated global extent of occurrence of 10,000,000 km2 (3,900,000 sq mi). On the other hand, the expansion and establishment of the species over large ranges has led it to be classed as an invasive species (although little, if any impact has been noted yet). [29]

Breeding

Cattle egret egg Heron garde-boeufs MHNT.jpg
Cattle egret egg
Adult feeding a nestling in Apenheul zoo Bubulcus ibis on nest, Apenheul Primate Park, Apeldoorn, Netherlands.jpg
Adult feeding a nestling in Apenheul zoo
A non-breeding adult eating a frog in The Gambia Bubulcus ibis -Gambia -frog in beak-8.jpg
A non-breeding adult eating a frog in The Gambia
Juvenile on Maui (note black bill) Starr 030628-0097 Neonotonia wightii.jpg
Juvenile on Maui (note black bill)

The cattle egret nests in colonies, which are often, but not always, found around bodies of water. [16] The colonies are usually found in woodlands near lakes or rivers, in swamps, or on small inland or coastal islands, and are sometimes shared with other wetland birds, such as herons, egrets, ibises and cormorants. The North American breeding season lasts from April to October. [16] In the Seychelles, the breeding season is April to October. [30]

The male displays in a tree in the colony, using a range of ritualised behaviours such as shaking a twig and sky-pointing (raising his bill vertically upwards), [31] and the pair forms over three or four days. A new mate is chosen in each season and when re-nesting following nest failure. [32] The nest is a small untidy platform of sticks in a tree or shrub constructed by both parents. Sticks are collected by the male and arranged by the female, and stick-stealing is rife. [12] The clutch size can be anywhere from one to five eggs, although three or four is most common. The pale bluish-white eggs are oval-shaped and measure 45 mm × 53 mm (1.8 in × 2.1 in). [33] Incubation lasts around 23 days, with both sexes sharing incubation duties. [16] The chicks are partly covered with down at hatching, but are not capable of fending for themselves; they become capable of regulating their temperature at 9–12 days and are fully feathered in 13–21 days. [34] They begin to leave the nest and climb around at 2 weeks, fledge at 30 days and become independent at around the 45th day. [32]

The cattle egret engages in low levels of brood parasitism, and there are a few instances of cattle egret eggs being laid in the nests of snowy egrets and little blue herons, although these eggs seldom hatch. [16] There is also evidence of low levels of intraspecific brood parasitism, with females laying eggs in the nests of other cattle egrets. As much as 30% extra-pair copulations have been noted. [35] [36]

The dominant factor in nesting mortality is starvation. Sibling rivalry can be intense, and in South Africa third and fourth chicks inevitably starve. [32] In the dryer habitats with fewer amphibians the diet may lack sufficient vertebrate content and may cause bone abnormalities in growing chicks due to calcium deficiency. [37] In Barbados, nests were sometimes raided by vervet monkeys, [18] and a study in Florida reported the fish crow and black rat as other possible nest raiders. The same study attributed some nestling mortality to brown pelicans nesting in the vicinity, which accidentally, but frequently, dislodged nests or caused nestlings to fall. [38]

Feeding

The cattle egret feeds on a wide range of prey, particularly insects, especially grasshoppers, crickets, flies (adults and maggots [39] ), and moths, as well as spiders, frogs, and earthworms. [40] [41] In a rare instance they have been observed foraging along the branches of a banyan tree for ripe figs. [42] The species is usually found with cattle and other large grazing and browsing animals, and catches small creatures disturbed by the mammals. Studies have shown that cattle egret foraging success is much higher when foraging near a large animal than when feeding singly. [43] When foraging with cattle, it has been shown to be 3.6 times more successful in capturing prey than when foraging alone. Its performance is similar when it follows farm machinery, but it is forced to move more. [44] In urban situations cattle egrets have also been observed foraging in peculiar situations like railway lines. [45]

A cattle egret will weakly defend the area around a grazing animal against others of the same species, but if the area is swamped by egrets it will give up and continue foraging elsewhere. Where numerous large animals are present, cattle egrets selectively forage around species that move at around 5–15 steps per minute, avoiding faster and slower moving herds; in Africa, cattle egrets selectively forage behind plains zebras, waterbuck, blue wildebeest and Cape buffalo. [46] Dominant birds feed nearest to the host, and obtain more food. [12]

The cattle egret may also show versatility in its diet. On islands with seabird colonies, it will prey on the eggs and chicks of terns and other seabirds. [26] During migration it has also been reported to eat exhausted migrating landbirds. [47] Birds of the Seychelles race also indulge in some kleptoparasitism, chasing the chicks of sooty terns and forcing them to disgorge food. [48]

Relationship with humans

Western cattle egrets waiting for scraps at the fish market of Victoria, Seychelles Bubulcus ibis Victoria 2.jpg
Western cattle egrets waiting for scraps at the fish market of Victoria, Seychelles

A conspicuous species, the cattle egret has attracted many common names. These mostly relate to its habit of following cattle and other large animals, and it is known variously as cow crane, cow bird or cow heron, or even elephant bird or rhinoceros egret. [16] Its Arabic name, abu qerdan, means "father of ticks", a name derived from the huge number of parasites such as avian ticks found in its breeding colonies. [16] [49]

The cattle egret is a popular bird with cattle ranchers for its perceived role as a biocontrol of cattle parasites such as ticks and flies. [16] A study in Australia found that cattle egrets reduced the number of flies that bothered cattle by pecking them directly off the skin. [50] It was the benefit to stock that prompted ranchers and the Hawaiian Board of Agriculture and Forestry to release the species in Hawaii. [26] [51] [52]

Not all interactions between humans and cattle egrets are beneficial. The cattle egret can be a safety hazard to aircraft due to its habit of feeding in large groups in the grassy verges of airports, [53] and it has been implicated in the spread of animal infections such as heartwater, infectious bursal disease [54] and possibly Newcastle disease. [55] [56]

Related Research Articles

<span class="mw-page-title-main">Egret</span> Type of bird of the heron family

Egrets are herons, generally long-legged wading birds, that have white or buff plumage, developing fine plumes during the breeding season. Egrets are not a biologically distinct group from herons and have the same build.

<span class="mw-page-title-main">Great blue heron</span> Species of bird

The great blue heron is a large wading bird in the heron family Ardeidae, common near the shores of open water and in wetlands over most of North and Central America, as well as far northwestern South America, the Caribbean and the Galápagos Islands. It is occasionally found in the Azores and is a rare vagrant to Europe. An all-white population found in south Florida and the Florida Keys is known as the great white heron. Debate exists about whether these white birds are a color morph of the great blue heron, a subspecies of it, or an entirely separate species.

<span class="mw-page-title-main">American white ibis</span> Bird in the ibis family

The American white ibis is a species of bird in the ibis family, Threskiornithidae. It is found from the southern half of the US East Coast, along the Gulf Coast states and south through most of the Caribbean coastal regions of Central America. This particular ibis species is a medium-sized wading bird, possessing an overall white plumage with black wing-tips, and having the typical downward-curving bill of the ibises, though of a bright red-orange color, the same hue as its long legs. Males are larger and have longer bills than females. The breeding range runs along the Gulf and Atlantic Coast, and the coasts of Mexico and Central America. Outside the breeding period, the range extends further inland in North America and also includes the Caribbean. It is also found along the northwestern South American coastline in Colombia and Venezuela. Populations in central Venezuela overlap and interbreed with the scarlet ibis. The two have been classified by some authorities as a single species.

<span class="mw-page-title-main">Heron</span> Family of birds

Herons are long-legged, long-necked, freshwater and coastal birds in the family Ardeidae, with 74 recognised species, some of which are referred to as egrets or bitterns rather than herons. Members of the genus Botaurus are referred to as bitterns, and, together with the zigzag heron, or zigzag bittern, in the monotypic genus Zebrilus, form a monophyletic group within the Ardeidae. Egrets do not form a biologically distinct group from herons, and tend to be named differently because they are mainly white or have decorative plumes in breeding plumage. Herons, by evolutionary adaptation, have long beaks.

<span class="mw-page-title-main">Grey heron</span> Long-legged predatory wading bird

The grey heron is a long-legged wading bird of the heron family, Ardeidae, native throughout temperate Europe and Asia, and also parts of Africa. It is resident in much of its range, but some populations from the more northern parts migrate southwards in autumn. A bird of wetland areas, it can be seen around lakes, rivers, ponds, marshes and on the sea coast. It feeds mostly on aquatic creatures which it catches after standing stationary beside or in the water, or stalking its prey through the shallows.

<span class="mw-page-title-main">Great egret</span> Species of bird

The great egret (Ardea alba), also known as the common egret, large egret, or great white egret or great white heron, is a large, widely distributed egret. The four subspecies are found in Asia, Africa, the Americas, and southern Europe. Recently, it has also been spreading to more northern areas of Europe. Distributed across most of the tropical and warmer temperate regions of the world, it builds tree nests in colonies close to water.

<span class="mw-page-title-main">Yellow-crowned night heron</span> Species of bird

The yellow-crowned night heron, is one of two species of night heron in genus Nyctanassa. Unlike the black-crowned night heron, which has a worldwide distribution, the yellow-crowned is restricted to the Americas. It is known as the bihoreau violacé in French and the pedrete corona clara or yaboa común in some Spanish-speaking countries.

<span class="mw-page-title-main">Snowy egret</span> Species of bird

The snowy egret is a small white heron. The genus name comes from Provençal French for the little egret, aigrette, which is a diminutive of aigron, 'heron'. The species name thula is the Araucano term for the black-necked swan, applied to this species in error by Chilean naturalist Juan Ignacio Molina in 1782.

<span class="mw-page-title-main">Little egret</span> Species of water bird

The little egret is a species of small heron in the family Ardeidae. It is a white bird with a slender black beak, long black legs and, in the western race, yellow feet. As an aquatic bird, it feeds in shallow water and on land, consuming a variety of small creatures. It breeds colonially, often with other species of water birds, making a platform nest of sticks in a tree, bush or reed bed. A clutch of three to five bluish-green eggs is laid and incubated by both parents for about three weeks. The young fledge at about six weeks of age.

<span class="mw-page-title-main">Cattle egret</span> Former genus of herons

The cattle egret is a cosmopolitan clade of heron in the genus Ardea found in the tropics, subtropics, and warm-temperate zones. According to the IOC bird list, it contains two species, the western cattle egret and the eastern cattle egret, although some authorities regard them as a single species. Despite the similarities in plumage to the egrets of the genus Egretta, it actually belong to the genus Ardea. Originally native to parts of Asia, Africa, and Europe, it has undergone a rapid expansion in its distribution and successfully colonised much of the rest of the world in the last century.

<span class="mw-page-title-main">Western reef heron</span> Species of bird

The western reef heron, also called the western reef egret, is a medium-sized heron found in southern Europe, Africa and parts of Asia. It has a mainly coastal distribution and occurs in several plumage forms: a slaty-grey plumage in which it can only be confused with the rather uncommon dark morph of the Little egret ; a white form which can look very similar to the little egret although the bill tends to be paler and larger and the black form with white throat E. g. gularis of West Africa. There are also differences in size, structure and foraging behaviour. There have been suggestions that the species hybridizes with the Little Egret, and based on this, some authors treat schistacea and gularis as subspecies of Egretta garzetta. Works that consider the Western Reef Heron as a valid species include the nominate gularis and schistacea as subspecies.

<span class="mw-page-title-main">White-faced heron</span> Species of bird

The white-faced heron also known as the white-fronted heron, and incorrectly as the grey heron, or blue crane, is a common bird throughout most of Australasia, including New Guinea, the islands of Torres Strait, Indonesia, New Zealand, and all but the driest areas of Australia.

<span class="mw-page-title-main">Reddish egret</span> Species of bird

The reddish egret is a medium-sized heron that is a resident breeder in Central America, the Bahamas, the Caribbean, the Gulf Coast of the United States, and Mexico. The egret is known for its unusual foraging behavior compared to other herons as well as its association with mud flats, its habitat of choice.

<span class="mw-page-title-main">Tricolored heron</span> Species of bird

The tricolored heron, formerly known as the Louisiana heron, is a small species of heron native to coastal parts of the Americas. The species is more solitary than other species of heron in the Americas and eats a diet consisting mostly of small fish.

<span class="mw-page-title-main">Little blue heron</span> Species of bird

The little blue heron is a small heron of the genus Egretta. It is a small, darkly colored heron with a two-toned bill. Juveniles are entirely white, bearing resemblance to the snowy egret. During the breeding season, adults develop different coloration on the head, legs, and feet.

<span class="mw-page-title-main">Medium egret</span> Species of bird

The medium egret, median egret, smaller egret or intermediate egret, is a medium-sized heron. Some taxonomists put the species in the genus Egretta or Mesophoyx. It is a resident breeder in southern and eastern Asia.

<span class="mw-page-title-main">Least bittern</span> Species of bird

The least bittern is a small heron, the smallest member of the family Ardeidae found in the Americas. This species was formerly placed in the genus Ixobrychus.

<i>Egretta</i> Genus of birds

Egretta is a genus of medium-sized herons, mostly breeding in warmer climates.

<span class="mw-page-title-main">Capped heron</span> Species of bird

The capped heron is a water bird endemic to the neotropics, inhabiting rainforest from the center of Panama to the south of Brazil. It is the only species of the genus Pilherodius, and one of the least known of the heron family, Ardeidae. It is superficially similar to the group of the night herons, but is active during daytime or at twilight.

<span class="mw-page-title-main">Eastern cattle egret</span> Species of bird

The eastern cattle egret is a species of heron found in the tropics, subtropics and warm temperate zones. Formerly, most taxonomic authorities lumped this species and the western cattle egret together, but the two cattle egrets are now treated as separate species. Despite the similarities in plumage to the egrets of the genus Egretta, it is more closely related to the herons of Ardea. It is native to southern and eastern Asia, and Australasia.

References

  1. ↑ Linnaeus, C. (1758). Systema naturae per regna tria naturae, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. Tomus I. Editio decima, reformata (in Latin). Holmiae [Stockholm]: Laurentii Salvii. p. 144. A. capite laevi, corpore albo, rostro flavescente apice pedibusque nigris
  2. ↑ Bonaparte, Charles Lucien (1855). "[untitled]". Annales des Sciences Naturelles comprenant la zoologie (in French). 4 (1): 141.
  3. ↑ Gill, Frank; Donsker, David; Rasmussen, Pamela, eds. (August 2024). "Ibis, spoonbills, herons, Hamerkop, Shoebill, pelicans". IOC World Bird List Version 14.2. International Ornithologists' Union. Retrieved 26 September 2024.
  4. ↑ Hruska, J.P.; Holmes, J.; Oliveros, C.; Shakya, S.; Lavretsky, P.; McCracken, K.G.; Sheldon, F.H.; Moyle, R.G. (2023). "Ultraconserved elements resolve the phylogeny and corroborate patterns of molecular rate variation in herons (Aves: Ardeidae)". Ornithology: ukad005. doi:10.1093/ornithology/ukad005.
  5. ↑ Jobling, James A. "Ardea". The Key to Scientific Names. Cornell Lab of Ornithology. Retrieved 25 September 2024.
  6. ↑ "Ibis". Webster's Online Dictionary. Webster's . Retrieved 15 March 2008.
  7. ↑ Jobling, James A (2010). The Helm Dictionary of Scientific Bird Names. London: Christopher Helm. p.  201. ISBN   978-1-4081-2501-4.
  8. ↑ Sheldon, F.H. (1987). "Phylogeny of herons estimated from DNA-DNA hybridization data". The Auk. 104 (1): 97–108. doi: 10.2307/4087238 . JSTOR   4087238.
  9. ↑ McCarthy, Eugene M. (2006). Handbook of Avian Hybrids of the World. Oxford University Press. p. 190. ISBN   0-19-518323-1.
  10. 1 2 3 "Cattle Egret". All About Birds. Cornell Lab of Ornithology . Retrieved 28 February 2008.
  11. ↑ Krebs, E.A.; Hunte, W.; Green, D.J. (2004). "Plume variation, breeding performance and extra-pair copulations in the cattle egret". Behaviour. 141 (4): 479–499. doi:10.1163/156853904323066757.
  12. 1 2 3 McKilligan, Neil (2005). Herons, Egrets and Bitterns: Their Biology and Conservation in Australia (PDF extract). CSIRO Publishing. pp. 88–93. ISBN   0-643-09133-5.
  13. ↑ Martin, G.R.; Katzir, G. (1994). "Visual Fields and Eye Movements in Herons (Ardeidae)". Brain, Behavior and Evolution. 44 (2): 74–85. doi:10.1159/000113571. PMID   7953610.
  14. ↑ Rojas, L.M.; McNeil, R.; Cabana, T.; Lachapelle, P. (1999). "Behavioral, Morphological and Physiological Correlates of Diurnal and Nocturnal Vision in Selected Wading Bird Species". Brain, Behavior and Evolution. 53 (5–6): 227–242. doi:10.1159/000006596. PMID   10473901. S2CID   21430848.
  15. ↑ Katzir, G.; Strod, T.; Schectman, E.; Hareli, S.; Arad, Z. (1999). "Cattle egrets are less able to cope with light refraction than are other herons". Animal Behaviour. 57 (3): 687–694. doi:10.1006/anbe.1998.1002. PMID   10196060. S2CID   11941872.
  16. 1 2 3 4 5 6 7 8 9 10 11 12 Telfair II, Raymond C. (2006). Poole, A. (ed.). "Cattle Egret (Bubulcus ibis)". The Birds of North America Online. Ithaca: Cornell Lab of Ornithology. doi:10.2173/bna.113. Archived from the original on 17 May 2008.{{cite journal}}: CS1 maint: bot: original URL status unknown (link)
  17. 1 2 3 Martínez-Vilalta, A.; Motis, A. (1992). "Family Ardeidae (Herons)". In del Hoyo, J.; Elliot, A.; Sargatal, J. (eds.). Handbook of the Birds of the World . Vol. 1: Ostrich to Ducks. Lynx Edicions. pp. 401–402. ISBN   84-87334-09-1.
  18. 1 2 Krebs, Elizabeth A.; Riven-Ramsey, Deborah; Hunte, W. (1994). "The Colonization of Barbados by Cattle Egrets (Bubulcus ibis) 1956–1990". Colonial Waterbirds. 17 (1). Waterbird Society: 86–90. doi:10.2307/1521386. JSTOR   1521386.
  19. 1 2 Crosby, G. (1972). "Spread of the Cattle Egret in the Western Hemisphere" (PDF). Journal of Field Ornithology. 43 (3): 205–212. doi:10.2307/4511880. JSTOR   4511880.
  20. ↑ "First cattle egrets breed in UK". BBC News. 23 July 2008. Retrieved 24 July 2008.
  21. ↑ Nightingale, Barry; Dempsey, Eric (2008). "Recent reports" (PDF). British Birds . 101 (2): 108.
  22. ↑ Barrett, Anne (15 January 2008). "Flying in ... to make new friends down on the farm". Irish Independent .
  23. ↑ Botkin, D.B. (2001). "The naturalness of biological invasions". Western North American Naturalist. 61 (3): 261–266.
  24. ↑ Silva, M.P.; Coria, N.E.; Favero, M.; Casaux, R.J. (1995). "New Records of Cattle Egret Bubulcus ibis, Blacknecked Swan Cygnus melancoryhyphus and White-rumped Sandpiper Calidris fuscicollis from the South Shetland Islands, Antarctica" (PDF). Marine Ornithology. 23: 65–66.
  25. ↑ Dutson, G.; Watling, D. (2007). "Cattle egrets (Bubulcus ibis) and other vagrant birds in Fiji" (PDF). Notornis. 54 (4): 54–55.
  26. 1 2 3 Lever, C. (1987). Naturalised Birds of the World. Harlow, Essex: Longman Scientific & Technical. pp. 15–17. ISBN   0-582-46055-7.
  27. ↑ Mullarney, Killian; Svensson, Lars; Zetterström, Dan; Grant, Peter J. (2001). Birds of Europe. Princeton University Press. ISBN   0-691-05054-6.
  28. ↑ Arendt, Wayne J. (1988). "Range Expansion of the Cattle Egret (Bubulcus ibis) in the Greater Caribbean Basin". Colonial Waterbirds. 11 (2). Waterbird Society: 252–262. doi:10.2307/1521007. JSTOR   1521007.
  29. ↑ "Bubulcus ibis (bird)". Global Invasive Species Database. Archived from the original on 4 March 2016. Retrieved 6 February 2008.
  30. ↑ Skerrett, A.; Bullock, I.; Disley, T. (2001). Birds of the Seychelles. Helm Field Guides. ISBN   0-7136-3973-3.
  31. ↑ Marchant, S.; Higgins, P.J. (1990). Handbook of Australian, New Zealand and Antarctic Birds . Vol. 1 (Ratites to Ducks). Oxford University Press. ISBN   0-19-553068-3.
  32. 1 2 3 Kushlan, James A.; Hancock, James (2005). Herons. Oxford University Press. ISBN   0-19-854981-4.
  33. ↑ Beruldsen, G. (2003). Australian Birds: Their Nests and Eggs. Kenmore Hills, Queensland: self. p. 182. ISBN   0-646-42798-9.
  34. ↑ Hudson, Jack W.; Dawson, William R.; Hill, Richard W. (1974). "Growth and development of temperature regulation in nestling cattle egrets". Comparative Biochemistry and Physiology A. 49 (4): 717–720. doi:10.1016/0300-9629(74)90900-1. PMID   4154173.
  35. ↑ Fujioka, M.; Yamagishi, S. (1981). "Extra-marital and pair copulations in cattle egret". The Auk. 98 (1): 134–144. doi:10.1093/auk/98.1.134. JSTOR   4085616.
  36. ↑ McKilligan, N.G. (1990). "Promiscuity in the cattle egret (Bubulcus ibis)". The Auk. 107 (2): 334–341. doi: 10.2307/4087617 . JSTOR   4087617.
  37. ↑ Phalen, David N.; Drew, Mark L.; Contreras, Cindy; Roset, Kimberly; Mora, Miguel (2005). "Naturally occurring secondary nutritional hyperparathyroidism in cattle egrets (Bubulcus ibis) from central Texas". Journal of Wildlife Diseases. 41 (2): 401–415. doi: 10.7589/0090-3558-41.2.401 . PMID   16107676.
  38. ↑ Maxwell, G.R. II; Kale, H.W. II (1977). "Breeding biology of five species of herons in coastal Florida". The Auk. 94 (4): 689–700. doi: 10.2307/4085265 . JSTOR   4085265.
  39. ↑ Seedikkoya, K.; Azeez, P.A.; Shukkur, E.A.A. (2007). "Cattle egret as a biocontrol agent" (PDF). Zoos' Print Journal. 22 (10): 2864–2866. doi:10.11609/jott.zpj.1731.2864-6. Archived from the original (PDF) on 2011-09-29. Retrieved 2017-04-09.
  40. ↑ Siegfried, W.R. (1971). "The Food of the Cattle Egret". Journal of Applied Ecology. 8 (2). British Ecological Society: 447–468. doi:10.2307/2402882. JSTOR   2402882.
  41. ↑ Fogarty, Michael J.; Hetrick, Willa Mae (1973). "Summer Foods of Cattle Egrets in North Central Florida". The Auk. 90 (2): 268–280. JSTOR   4084294.
  42. ↑ Chaturvedi, N. (1993). "Dietary of the cattle egret Bubulcus ibis coromandus (Boddaert)". Journal of the Bombay Natural History Society. 90 (1): 90.
  43. ↑ Grubb, T. (1976). "Adaptiveness of Foraging in the Cattle Egret". Wilson Bulletin. 88 (1): 145–148. JSTOR   4160720.
  44. ↑ Dinsmore, James J. (1973). "Foraging Success of Cattle Egrets, Bubulcus ibis". American Midland Naturalist. 89 (1). The University of Notre Dame: 242–246. doi:10.2307/2424157. JSTOR   2424157.
  45. ↑ Devasahayam, A. (2009). "Foraging behaviour of cattle egret in an unusual habitat". Newsletter for Birdwatchers . 49 (5): 78.
  46. ↑ Burger, J.; Gochfeld, M. (1993). "Making Foraging Decisions: Host Selection by Cattle Egrets Bubulcus ibis". Ornis Scandinavica. 24 (3). Blackwell Publishing: 229–236. doi:10.2307/3676738. JSTOR   3676738.
  47. ↑ Cunningham, R.L. (1965). "Predation on birds by the Cattle Egret" (PDF). The Auk. 82 (3): 502–503. doi:10.2307/4083130. JSTOR   4083130.
  48. ↑ Feare, C.J. (1975). "Scavenging and kleptoparasitism as feeding methods on Seychelles Cattle Egrets, Bubulcus ibis". Ibis. 117 (3): 388. doi:10.1111/j.1474-919X.1975.tb04229.x.
  49. ↑ McAtee, Waldo Lee (October 1925). "The Buff-backed Egret (Ardea ibis L., Arabic Abu Qerdan) as a Factor in Egyptian Agriculture" (PDF). The Auk. 42 (4): 603–604. doi:10.2307/4075029. JSTOR   4075029.
  50. ↑ McKilligan, N.G. (1984). "The food and feeding ecology of the Cattle Egret Ardeola ibis when nesting in south-east Queensland". Australian Wildlife Research. 11 (1): 133–144. doi:10.1071/WR9840133.
  51. ↑ Berger, A.J. (1972). Hawaiian Birdlife. Honolulu: University of Hawaii Press. ISBN   0-8248-0213-6.
  52. ↑ Breese, P.L. (1959). "Information on Cattle Egret, a Bird New to Hawaii". Elepaio. 20. Hawaii Audubon Society: 33–34.
  53. ↑ Paton, P.; Fellows, D.; Tomich, P. (1986). "Distribution of Cattle Egret Roosts in Hawaii With Notes on the Problems Egrets Pose to Airports". Elepaio. 46 (13): 143–147.
  54. ↑ Fagbohun, O.A.; Owoade, A.A.; Oluwayelu, D.O.; Olayemi, F.O. (2000). "Serological survey of infectious bursal disease virus antibodies in cattle egrets, pigeons and Nigerian laughing doves". African Journal of Biomedical Research . 3 (3): 191–192.
  55. ↑ "Heartwater" (PDF). Animal and Plant Health Inspection Service. U.S. Department of Agriculture. Archived from the original (PDF) on 23 May 2006. Retrieved 13 April 2008.
  56. ↑ Fagbohun, O.A.; Oluwayelu, D.O.; Owoade, A.A.; Olayemi, F.O. (2000). "Survey for antibodies to Newcastle Disease virus in cattle egrets, pigeons and Nigerian laughing doves" (PDF). African Journal of Biomedical Research. 3: 193–194.
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