Spring is the time for this burst of colour in the form of butterflies. Photo: Jane Simpson
Spring is the time for this burst of colour in the form of butterflies. Photo: Jane Simpson

Floating cloud of butterflies heralds our spring

THE arrival of spring in Noosa has been dramatic this year, with dry conditions and bushfires affecting many different parts of our shire.

With the warmer weather, nectar bearing trees have been flowering in profusion and a whole population of insects has been busy making the most of the new sources of food that are locally available.

Last spring, under more pleasant conditions, I was enjoying a walk around our own botanic gardens at Lake Macdonald, when I came across a floating cloud of butterflies above a garden of shrubbery near the entrance.

The butterflies had the most beautiful colours of blue, white and aqua and the way that the angle of sunlight was shining on their wings, it appeared almost like I was looking at miniature bands of delicate stained glass.

The butterflies that I had encountered were the blue triangle (Graphium sarpedon), a species of swallowtail butterfly. With one of the widest ranges, they are found from southern coastal New South Wales right up the eastern seaboard to Cape York and into New Guinea and Malaysia.

Both sexes of these iridescent butterflies are very similar, except that the males have a pretty mark consisting of a rosette of scent bearing fine hairs on the inner edge of each hindwing which when dispersed into the air, entices the ladies in for a closer look.

The yellowish-green egg is globular in shape and is laid singly by the butterfly on the young shoots of their food plants, namely the camphor laurel (Cinnamomum camphora), sassafras (Geijera salicifolia), and the water gum (Tristaniopsis laurina).

The fully grown caterpillar stage is green and strongly humped.

Across the third segment is a yellow bar with a spine at each end. Above the legs is a creamy lateral line.

The chrysalis is green in colour and is attached by its tail and a central silken girdle and is usually found on the sheltered underside of a leaf.

If you visit Noosa’s Botanic Gardens, look out for these stained glass wonders of nature.