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The cattle egret (Bubulcus ibis) is a cosmopolitan species of heron (family Ardeidae) found in the tropics, subtropics and warm temperate zones. It is the only member of the monotypic genus Bubulcus, although some authorities regard its two subspecies as full species, the western cattle egret and the eastern cattle egret. 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. 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 oftenaccompany 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.
Some populations of cattle egrets are migratory, others are dispersive, and distinguishing between the two can be difficult for this species. In many areas populations can be both sedentary and migratory. In the northern hemisphere, migration is from cooler climes to warmer areas, but cattle egrets nesting in Australia migrate to cooler Tasmania and New Zealand in the winter and return in the spring. 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. Populations in southern India appear to show local migrations in response to the monsoons. They move north from Kerala after September. During winter, many birds have been seen flying at night with flocks of Indian pond herons(Ardeola grayii) on the south-eastern coast of India and a winter influx has also been noted in Sri Lanka.
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.
The cattle egret nests in colonies, which are often, but not always, found around bodies of water. 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 breeding season varies within South Asia. Nesting in northern India begins with the onset of monsoons in May. The breeding season in Australia is November to early January, with one brood laid per season. The North American breeding season lasts from April to October. In the Seychelles, the breeding season of the subspecies B.i. seychellarum is April to October.
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), and the pair forms over three or four days. A new mate is chosen in each season and when re-nesting following nest failure. 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. 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). Incubation lasts around 23 days, with both sexes sharing incubation duties. 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. They begin to leave the nest and climb around at 2 weeks, fledge at 30 days and become independent at around the 45th day.
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. 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.
The dominant factor in nesting mortality is starvation. Sibling rivalry can be intense, and in South Africa third and fourth chicks inevitably starve.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. In Barbados, nests were sometimes raided by vervet monkeys, 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. In Australia, Torresian crows, wedge-tailed eagles and white-bellied sea eagles take eggs or young, and tick infestation and viral infections may also be causes of mortality. from Wikipedia, the free encyclopedia
Photos and videos Amochostos, Oroklini by George Konstantinou
Photos Ammochostos 10/4/2018 by George Konstantinou
Videos Ammochostos 18/5/2018 by George Konstantinou
Nesting in Mari pond - Cyprus 29/5/2023
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