Munching Caterpillar News

The Story of the Confused Caterpillar

February 16, 2015

Back in December a member of the Publicity team here at Butterfly Conservation found a confused caterpillar on a dogs bed! Wanting to give him a better chance in life they picked him up and popped him in to a cosy tank with a selection of leaves for him to munch on. They named him ‘Hanky’ and handed him over to Munching Caterpillars so we could show him off to children and hopefully help us to inspire families about butterflies, moths and caterpillars.

'Hanky' the Caterpillar

‘Hanky’ the Confused Caterpillar

Hanky, however had other ideas. We soon noticed he didn’t want to eat anything we gave him. We knew he would eventually turn into a moth, and we were pretty sure we knew what species of moth – a Large Yellow Underwing. We tried giving him lots of different foodplants that Large Yellow Underwings normally like to eat, but he was having none of it!

Large Yellow Underwings normally survive the winter as a caterpillar; hiding from the cold by dropping down to the bottom of grasses or covering themselves in a thin layer of soil. They don’t usually pupate until around March, when they have eaten a lot and are quite large. When they are ready to pupate they stop eating and look for a patch of soil to bury themselves in.

Hanky was not eating and was already quite large… We decided to add a layer of compost to his tank. Within hours Hanky had buried himself completely!

Two months later, on Sunday 15th February, Hanky wriggled out of his pupal casing as a fully formed moth! He dug himself a tunnel out of the soil and crawled to the edge of his tank. He climbed a little way up and pumped his new wings full of hemolymph (moth’s blood). After sitting there for a few more minutes his new wings had dried and he was ready to fly!

The only problem is… he is 5 months early! Large Yellow Underwings normally emerge between July and September!

'Hanky' a Large Yellow Underwing

‘Hanky’ with new wings

We had a great summer in 2014, so a lot of moth species emerged slightly earlier than usual. The warmer temperatures continuing in to late summer and autumn meant there was still plenty of food and warmth for caterpillars to survive. Combine that with bringing ‘Hanky’ indoors where it is much warmer than outdoors, we believe he got a bit confused and developed much faster than he was meant to in the wild!

The leftover pupal case

The leftover pupal case

So what now?! Well Hanky will be given a small colourful dot on his/her wings to tell other moth trappers that this moth was raised in captivity and therefore they shouldn’t record it. She/he will then be released on a dry, warmish day. Although Hanky will probably never find a mate to breed with, there are plenty of spring flowers appearing now so she/he should be able to find nectar to feed on.