It has been many years since Melbourne Zoo has hosted the impressive Hercules moth (Coscinocera hercules). A recent delivery of young caterpillars from Queensland can currently be seen in the lifecycle display inside our Butterfly House. Visitors can witness the lifecycle of this species up close and look in wonder at the size these caterpillars can grow too!
The Hercules moth is the largest moth in Australia and can be found in north Queensland. Caterpillars grow up to 14 centimetres long and weigh up to 29 grams. When they emerge as moths the female’s wingspan is a massive 28 centimetres, making it one of the largest of any moth species in the world!
The female moth can lay up to 250 eggs in her very short lifespan. The eggs are brown/orange and can be laid in singular pattern or small groups. Adult moths lack mouthparts so do not eat and can only live as long as the stored energy in their body lasts, surviving usually only up to 2 weeks. When they emerge as moths it is the males with their long tails that do most of the flying, being attracted by pheromones produced by the female to locate her and mate.
When the caterpillar hatches from it egg it is covered in a thick coating of white wax. As they feed and grow they change to a beautiful pale blue-green colour with soft yellow spines down the entire length of their bodies. When fully grown the caterpillar will spin a large silk cocoon. It will then go inside to change into a pupa and over many weeks eventually emerge as a magnificent moth!
In the wild the caterpillars feed from a number of different rainforest plants. Here at Melbourne Zoo they are feeding on the leaves of the Bleeding Heart tree (Omalanthus populifolius). They have a very healthy appetite and can be seen feeding vigorously.
Next time you visit the Butterfly House I would recommend you drop in to see one of the most impressive caterpillars in the natural world! And stay tuned to see them in all their adult glory in the not too distant future…