Gangly heron with significant variation in plumage. Distinct dark morph is slate-gray with a white throat, while the palest morph is white with a yellow bill and lores. Pale gray intermediate morphs can also be found. Little Egret can look similar, but it has a darker bill than the white morph of the Western Reef-Heron. Primarily a coastal inhabitant, foraging on shorelines and in estuaries, but can also be found at some inland water bodies.
The western reef heron (Egretta gularis ), 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 (Egretta garzetta ); 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.
The western reef heron's breeding habitat is coastal wetlands. In the Red Sea region the breeding season is from June to August. The nominate subspecies breeds in West Africa from late April to September. In India the breeding season is during the monsoon rains from April to August and end of May in the former breeding colony at Chilaw in Sri Lanka. Most of the breeding colonies in Gujarat in western India were on mangroves. They nest in colonies usually of their own species but sometimes with other egrets and smaller herons, usually on platforms of sticks placed in trees or shrubs. The male fetches sticks of the nest while the female places them to form the platform. The nest height varies from about 5 to 15 meters, but very low nesting (as low as 0.6 meters) has been observed in mangrove trees in salt pans. The usual clutch is three to four eggs which are light blue as in the little egret. Incubation begins when the first egg is laid resulting in chicks with size disparities. Both parents take turns to incubate and the eggs hatch after about 23 to 24 days. The chicks are white with grey dapples. Young birds sometimes die after falling off from the nest platform. Adults will shade the chicks during the hotter parts of the day. Predators of eggs include rats and young chicks may be taken by cats and crows. Adults usually guard the nest when eggs or young chicks are present. Adults feed the young by regurgitating semi-digested food at the nest. This diet includes mainly small fishes of the families Clupeidae, Gobiidae and Engraulidae. The young birds leave the nest after about a month.
It occurs mainly on the coasts in tropical west Africa, the Red Sea, the Persian Gulf (Iran) extending east to India. It also occurs in the Lakshadweep Islands and Sri Lanka where breeding was once recorded at Chilaw. The nominate subspecies breeds in west Africa from Mauritania to Gabon. Birds may also be found off the mainland such as in the Canary Islands. Small numbers breed in Spain. Subspecies schistacea is found from the Red Sea coast east round the Indian coast. Breeding colonies are known from the east coast of India around Pulicat Lake. They occasionally occur further inland.
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