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Friday, 24 November 2017

24-11-2017 PEGO MARJAL, ALICANTE - CATTLE EGRET (Bubulcus ibis)


Compared with other herons, Western Cattle Egrets are noticeably small and compact. They have relatively short legs and a short thick neck. The straight, daggerlike bill is shorter and thicker than other herons. They have medium-length, broad, rounded wings.

Adult Western Cattle Egrets are all white with a yellow bill and legs. In breeding plumage they have golden plumes on their head, chest, and back. Juveniles have dark legs and bill.

Western Cattle Egrets stalk insects and other small animals on the ground in grassy fields. They are much less often seen in water than other herons. They nest in dense colonies of stick nests in trees or emergent wetlands, often mixed with other species of herons.

They forage in flocks in upland areas such as pastures and fields, generally focusing on drier habitats than other species of white herons.


The Western Cattle-Egret is a gregarious, white, upland heron ( Ardeidae ), easily recognized by its foraging association with grazing animals and its exaggerated head strut. It is distinguished from the Eastern Cattle-Egret (Ardea coromanda) by having breeding plumage less buff-orange in the head and neck regions. Its preference for grasslands, lawns, pastures and grazing animals is very different from that of other herons and egrets which tend to feed in or near water rather than in close association with livestock. In Britain and Europe it is also known as the buffalo heron in reference to the colour of its breeding plumes; but in many languages ​​it is simply called the cow crane, cow heron or cow bird, or is named after the wild grazing animal with which it is usually associated; for example, elephant bird, rhinoceros egret or hippopotamus egret. The Western Cattle-Egret's Arabic name, Abu Qerdan, means "father of ticks" and refers to the abundance of ticks on Egyptian herons. Other names that include the word tick, such as Tick-eating Bird, refer to the mistaken belief that they pick up ticks attached to grazing animals; instead, most of their prey are insects disturbed by grazing animals. Derivation of scientific name:Bubulcus(the previous genus) from Latin "belonging to cattle" andibisfrom the Greek in reference to its slightly curved beak like that of the ibis.


This species began its remarkable range expansion in the late 19th century: spreading across the African continent, Madagascar and the Comoro Islands from 1900; into southern France and the Volga Delta in the 1950s; and, in the Americas, northeastern South America in the late 19th century, the Antilles in the mid-1950s, most of South America between the 1940s and 1970s, and Central and North America between the early 1950s and early 1970s. Its rapid expansion is well documented and studied, encouraging speculation about which aspects of its life history and ecology have most favoured the growth of its range and numbers. Indeed, this uncommon bird has provided a rare opportunity for global-scale comparative studies of its population dynamics and interactions with native colonial waterbirds as well as people.


Of particular interest are the economic aspects of the species' feeding habits and diet, medical and veterinary concerns, breeding colonies considered nuisances, and its status as a bioindicator of environmental conditions. The apparent keys to its spread and success are its dispersing tendencies, gregariousness, diet, adaptability to foraging - especially as humans convert ever larger tracts of landscape to pasture for livestock production and crop fields for rice agriculture - and its reproductive adaptability and success. Although numerous studies have been conducted in many parts of the world, data for its study in its original range are lacking.

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