A wildlife expert stumbled upon a strange sight while he was counting butterflies at a nature preserve in England recently, the CBC reported.

Chris Miller found it odd that an oak eggar moth caterpillar was at the top of a bush, because typically they wait until after dark to crawl to high spots so they can avoid predators such as birds. As Miller took a closer look, he realized that it wasn't a living caterpillar, but the exploded remains of one.

The caterpillar was suffering the effects of the baculovirus, which hijacks a caterpillar's brain, according to the Wildlife Trust for Lancashire, Manchester and North Merseyside. After the caterpillar crawls to a high spot and dies, the body liquefies and explodes, infecting other caterpillars below it.

Birds can also pick up the caterpillar corpses and carry them to new locations, spreading the virus. However, scientists aren't too concerned about the baculovirus wiping out the oak eggar moth caterpillar population, as the virus usually dies out on its own, the CBC reported.