Adult butterflies and moths are increasingly scarce now that autumn has taken hold, but there are still plenty of caterpillars to spot. Indeed, this is one of the prime times of year to look for larvae.
The summertime peak of butterfly and moth abundance has given rise to offspring, many of which are now in the caterpillar stage of their life cycle. What’s more, many are now fully grown and are wandering away from their foodplants in search of somewhere to hibernate or pupate.
In the garden, one of the most impressive caterpillars at this time of year is the Elephant Hawk-moth. Now some 8cm long and as thick as a finger, these giants can be spotted still feeding on fuchsia leaves or roaming the garden, prior to pupating for the winter hidden away on or under the soil surface. They make an impressive, even daunting sight but are completely harmless to humans and pets. Have a look at the eye-spot markings on the sides of their bodies near the head end. The Elephant Hawk-moth caterpillar can puff itself up to make these ‘eyes’ seem even bigger and more intimidating to would-be predators such as birds.
At the opposite extreme from the Elephant Hawk-moth are moth caterpillars so tiny that they can live within the thin tissue of a plant leaf. Autumn is a good time of year to look for these species too, which are generically known as ‘leaf-miners’ after the tunnels, blotches or tents that they make as their homes. A good one to look for in the garden is the Firethorn Leaf Miner Phyllonorycter leucographella on Pyracantha (Firethorn) shrubs. The mines are conspicuous and easy to spot on the upper surface of leaves, looking like long, translucent white tents. The mines ultimately cause the leaf to curl into a roll, so it is worth checking for these too on Pyracanthas.
There are plenty of other cool caterpillars to look out for in the garden, including the Vapourer moth, with its ‘shaving-brush’ tufts of yellow bristles and the yellow and a new generation of Large White caterpillars munching through brassicas and nasturtiums. If you have Purple Toadflax growing, then check for the caterpillars of the Toadflax Brocade. This scarce moth of south-east England is spreading to new areas and has recently been recorded in Wales for the first time. Its caterpillars are bluish-grey, liberally speckled with black dots and blotches and with yellow stripes running along the length of the body.
Out in the countryside, particularly on heathland, moors, downs, dunes and coastal grassland, the fully-grown, furry caterpillars of Fox Moth are on the move. These distinctive and often numerous creatures are black and covered with long hairs; dark brown and grey over most of the body and reddish-brown along the back. They can reach 7cm in length and wander freely during the day, at this time of year, before entering hibernation hidden in the leaf litter.
More information about finding and identifying caterpillars can be found on the Moths Count website.
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