Cattle Egret

Bubulcus ibis

Although there are two subspecies of cattle egret, it is the larger one that migrates to New Zealand from Australasia. The first rare sightings in New Zealand were recorded in the 1960’s, and the numbers of annual visitors steadily increased to a peak in the mid-1980s of well over 3000 birds. The egrets arrive on the western coasts during the period of April to May and stay for a short time to feed, before moving off to winter on their favoured farms or open habitats in other parts of New Zealand. In October to November, most cattle egrets will return to Australia except for some juveniles, who stay throughout the summer.

Cattle Egrets, like their name suggests, are often seen in flocks amongst grazing cattle. They have their favourite feeding spot and will return to the same pasture year after year, particularly if they are close to open bodies of fresh water. They often trail in the wake of grazing cattle (or infrequently, sheep or horses) eating the insects that are disturbed by the path of the animals. They eat a large array of insects, but the main bulk of their diet seems to be earthworms.  On dry pasture they snap insects from the air or leaf stalks while on wet ground they make shallow probes with their bill.

Sometimes they sit on the back of the cattle, but unlike cattle egret in tropical countries, this doesn’t seem to be for any particular purpose (such as a better vantage point for prey or for feeding on cattle parasites).  Cattle egrets are known as gregarious birds, but in New Zealand are very shy of people, and if disturbed will take off to fly in a large group.

Cattle egrets are short and stocky heron–like birds with a yellow sword-like bill and grey legs. Their wingspan covers about 85-95 centimetres. They are mainly white, but in the breeding season develop orange-buff plumage on the head, neck and back. Juveniles will be all white with a slight buff on the crown.

For the most part cattle egrets do not breed in New Zealand, but if they were to stay, they would nest in colonies with the nests built in clumps of trees or shrubs. The nest is an untidy mass of sticks in which 3 to 5 eggs are laid.  The eggs are an un-glossy white with a blue green tinge.

Except for a quiet, throaty "rick-rack" call at the breeding colony, the cattle egret is largely silent.