This afternoon I was wandering down my driveway, coffee in hand, to feed the fish in my pond when I noticed a small group of birdwatchers at the end of the driveway excitedly pointing up and and raising their binoculars to look at what I thought must be one of Paluma’s many special birds. The ladies who, judging from their T-shirts, were all members of Birdlife Townsville beckoned to me and pointed to the nearby telephone pole where, halfway up, was a magnificent male Hercules Moth. This is one of Paluma’s truly iconic wildlife species and while it has been seen around the village in previous years it is not very common and has been on my wish list to see for the last 30 years. I quickly went back up to the house and came down with my camera and telephoto lens and was able to capture some quite decent shots .
The Hercules Moth (Coscinocera hercules) is the largest moth in Australia (and possibly the world) with a wingspan of around 27cm in females. In terms of wing area (300cm2) it ranks as the world’s largest insect. The largest recorded specimen, from Innisfail, had a wing span of 36cm! The species occurs only in tropical Queensland and New Guinea.
The larvae of this moth are voracious eaters, preferring the leaves of the Bleeding Heart tree (Homalanthus) and the Cheese Tree (Glochidion), both of which are common around Paluma. The larvae get pretty big too (12cm) after gorging themselves for about 3 months. They then retreat into a cocoon where they can stay for up to 2 years before emerging.
The adult moths do not have functional mouth parts and thus cannot feed, spending their short adult lives (2-8 days) searching out mates and laying eggs The males are remarkably adept at finding females. Like other moths, the male has very large feathery antennae that are incredibly sensitive receptors for the very specific chemical (pheromone) released by the female. While I doubt that any experiments have been done on the Hercules moth, male silk moths are able to find a female up to 4.5km away and others species are said to be able to detect a single molecule of pheromone.
All told, it is a pretty impressive animal. My thanks to the ladies from Birdlife Townsville for showing it to me. They made my day!
Text and photos by Jamie Oliver
How exciting to see one of these magnificent moths. The late Roy Mackay told me they were, while not common, seen fairly frequently in Paluma. In the 12 years I have lived here, I have seen only one – a female. Surprising, as there are plenty of Homolanthus and Glochidion trees here to feed the caterpillars.
No mouths? I never knew this. Beautiful shot! Wish I was there to see it.