Bag Worm

Liothula species.

While I was inspecting the wattle flower buds to see if they survived the cold spell we had last month I found this bag worm case. At this time of year it probably contains a pupating moth. The case is woven from silk that the caterpillar builds around itself, and it is camouflaged with little sticks and leaf fragments. The bag is very tough. I remember as a child trying to tear one open.

The caterpillar partly emerges from the top to eat foliage at night. Waste drops out the hole at the bottom. The caterpillar can move about, carrying the bag with it. It so firmly attaches itself to twigs that the sap is restricted, causing swellings that give rise to galls. See the brown gall at the top of the picture.

When the moths emerge from the pupal stage the male leaves his bag and flies off in search of a female. The female remains in her bag waiting for a male to mate with her by pushing his back end into the bottom hole of her bag. The male then goes away to die, but at least he has had a few hours of freedom. The female lays her eggs and dies without ever leaving her bag.

While I was concentrating on getting the bag and the gall in the same shot the bellbird settled on the branch just above my head and gave out a glorious peal of song. The rich, pure notes were so penetrating they hurt my ears!

One year ago: one of my favourite fun shots.