They are known as Common Brown Butterflies. This is a dull name that does not describe their cheerful orange colour, or their furry orange bodies; or their sheer abundance across Victoria in suitable bush habitat.

Like most butterfly species, their seemingly aimless flittering and floating belies a very specific and time constrained life cycle.

The males emerge from their pupae (or cocoons) in spring, earlier than the females. Then the females begin to emerge, and this is when the numbers really peak.

The female Common Browns are larger, with a more distinct black and orange contrasting pattern. The males are paler with smaller spots and less black.

The males pursue the females by searching for them through the grasses.

If she is not interested in her suitor, the female simply drops to the ground and closes her wings.

Both male and female have very pale brown underwings, and when they close their wings they seem to disappear into the leaf litter. Mated pairs are joined back to back, with the larger female doing most of the flying.

After mating, the males die. There are lots of ill-looking males with tatty wings lying on our roadsides at the moment, especially after this severe cold snap.

The fertilised females then continue to enjoy life, reaping the nectar bounty of the Sweet Bursaria, which is flowering beautifully at the moment, and other summer flowers, both native and introduced.

When it gets really hot, she will aestivate, which is a form of summer hibernation, until May.

The female Common Brown will then lay her eggs on a suitable food plant, which may be a native grass such as Poa or Kangaroo Grass, or an introduced species such as Panic Veldt or Couch.

The delay in laying is a clever strategy, as it means that the young caterpillars get to feed on the fresh green growth after the Autumn rains. There is not much food around for caterpillars in the dry months of February and March.

After laying her eggs, the female dies. The young caterpillars will emerge 12 days later, and the cycle starts anew.

If you would like to know more about our local butterflies, the Museum of Victoria website has an excellent database at museumvictoria.com.au/bioinformat ics