Just look at this mighty beast! We think it’s an Oak Eggar moth caterpillar. We spotted it attempting to cross the road as we biked down a nearby lane. Crossing Devon’s lanes is usually pretty straight forward – but still Russian Roulette if you’re a moth caterpillar. We hastened this one on its way. If you find one do take care – the hairs make some people itch.
Oak Eggar and drinker moth caterpillars are amongst the commonest large hairy caterpillars people find in the UK, so that’s the obvious identification without asking an expert. There are some photographic ID sites online too. Butterfly Conservation has a page on the Oak Eggar and Wildlife Insight has a page with pics of the caterpillars.
Eggars get their name from the egg like papery cocoons the adult moths emerge from after their larval stage ends, and the Oak Eggar is so-named not because it is found on oak trees but because the cocoon looks like an acorn. Interestingly, the Oak Eggar overwinters as larvae and then feeds up in the spring, going into pupation in July and emerging as an adult from August. The adults are attracted to light so maybe we’ll be able to find one of those later in the summer!