This is a rare occurrence, being the first such bird known at the lake for 50 years or more.

As the accompanying photo shows, it is a clean white bird, with the usual dull red beak, pinkish legs and dark eye.

The dark eye indicates that it is not an albino, despite its all-white plumage.

Technically, it could be described as leucistic.

The fact that the white swamphen has turned up recently indicates that swamphens - and no doubt other waterbirds - are moving frequently across the Ballarat district.

Its appearance as an adult indicates that it is at least one year old, and that it has come from some other part of the Ballarat district or beyond.

With the large number of observant people around the Lake Wendouree area, we can claim that it was not hatched here.

The purple swamphen has a wide range across most of eastern Australia.

Like most Australian waterbirds, it moves from place to place as water-levels rise and fall.

At Lake Wendouree it is always present, but its numbers vary quite a lot throughout the year and from year to year, indicating considerable - but almost imperceptible - movement.

Swamphens appear to be clumsy fliers when we see them fly at Lake Wendouree and elsewhere, but they can obviously fly a long way once they rise high and head off. Long-distance flights take place at night.

The current white swamphen is seen mostly on the island in the lower pool of the North Gardens Wetlands.

This is the pool closest to Wendouree Parade.

It is often found in the grass and other thick vegetation on the island.

Most sightings are from the Wendouree Parade side of that pool, where it is usually seen with one or two other purple swamphens.

It has also been seen in other places nearby, including in Fairyland on the other side of Wendouree Parade.

It is a slightly nervous bird, not always easy to locate or observe.

It prefers to remain in the shelter of tall grasses and other vegetation.

At most times of the year the common wedge-pea is not noticed, but its large, pure yellow summer flowers make it conspicuous at this time of the year when many other wildflowers have finished.

It is a small plant, seldom more than 30 centimetres tall.

Its leaflets are small and narrow, in threes, often with a tinge of blue.

It is known to botanists as Gompholobium huegelii.

Pink-spotted hyacinth orchids are now also coming into flower.

How did the sugar ant get its name? What is its natural food? Y.F., Wallace.

The sugar ant's name comes from its liking for sweet foods of all types including sugar, confectionery and biscuits.

The natural food of this orange-and-black 10mm ant is flower nectar, sweet secretions from other insects, and sometimes small insects with a high sugar content.

Insects that feed on sap or nectar like various grubs, moths and beetles are also food for sugar ants.

The sugar ant feeds on a wide range of other foods too.

In some places the sugar ant is a nuisance inside, seeking sweet substances in kitchens. This does not seem to be a common habit in the Ballarat district, where it remains mostly outdoors.

Sugar ants do not sting, but they can bite with their jaws.