|Afrikaans:||Veereier / Bosluisvoël|
|Zulu:||iLanda / inGevu / umLindankomo|
|Tswana:||Manawane / Mmamoleane / Modisane|
|Tsonga:||Dzandza / Munyangana / Muthecana / Nyonimahlopi|
|South Sotho:||Leholosiane / Leholotsiane|
Identification. The Western Cattle Egret (Bubulcus ibis) is a stocky heron, 46 – 56 cm long, and weighs 270 – 512 g. It has a relatively short thick neck, sturdy bill, and a hunched posture. The non-breeding adult has mainly white plumage, a yellow bill and the legs vary from dark brown to yellow, with black toes.
A breeding Western Cattle Egret has a red bill and buff plumage on the head, breast and mantle. The legs turn red. 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 as well as black legs.
Habitat. The Western Cattle Egret inhabits open grassy areas such as meadows, livestock pastures, semi-arid steppe and open savanna grassland, dry arable fields, artificial grassland sites (e.g. lawns, parks, road margins and sports fields), flood-plains, freshwater swamps, wet pastures, shallow marshes, mangroves and irrigated grasslands. Most often in the company of cattle or game. It rarely occupies marine habitats or forested areas and it shows a preference for freshwater although it may also use brackish or saline habitats.
Diet. The Western Cattle Egret feeds on a wide range of prey, particularly insects. It prefers grasshoppers, crickets, flies (adults and maggots), and moths. In addition it feeds on spiders, frogs, and earthworms. The Western Cattle Egret is usually found with cattle and other large grazing and browsing animals. It feeds on the insects and worms disturbed by the mammals. During migration it has been reported to eat exhausted migrating birds.
A Western 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, Western Cattle Egrets selectively forage around species that move at around 5–15 steps per minute, avoiding faster and slower moving herds. In Africa Western Cattle Egrets selectively forage behind Zebras, Waterbuck, Blue Wildebeest and Cape Buffalo. Dominant birds feed nearest to the host and obtain more food.
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.
Call. The Western Cattle Egret’s call is a typical heron-like quiet, throaty “rick-rack” call at the breeding colony, but otherwise largely silent.
Breeding. The Western Cattle Egret nests in colonies. 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 is June to December in the southern areas and October to February in the northern areas.
The male displays in a tree in the colony. 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. 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 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.
South African Distribution. The Western Cattle Egret is a common resident throughout South Africa.
Port Elizabeth Area. There’s an abundance of Western Cattle Egrets in Port Elizabeth. They may be seen in virtually any open field and along most of the river banks in Port Elizabeth.
Conservation Status – LC (Least Concern)1 This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). The population trend appears to be increasing, and hence the species does not approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is extremely large, and hence does not approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.