The Common Brimstone (Gonepteryx rhamni) may often be the first butterfly to be sighted in early spring. When it comes to caterpillars, it’s generally the Small Tortoiseshell (Aglais urticae) that appears first.
Caterpillars of the Small Tortoiseshell are not only present early, they’re also easy to sight from distance. Living in colonies they build a web at a very early stage (see photos). Later on, once they’ve grown in size, they will start moving more individually. The web is only present during the early stage, but it remains on the nettles for weeks giving hint that caterpillars can be found.
If you have any intention to raise caterpillars yourself try finding some of this particular species. They’re easy to raise and don’t require too much care-taking. Some fresh nettles every second day or so and they’re happy.
One tip though. The younger the caterpillars you find, the better chances you have to get butterflies. Older caterpillars have an increased risk of being infected by parasites. This means it may not be a butterfly hatching from the chrysalis, but a nasty parasitoid wasp. Nevertheless, regardless on what will hatch, you’ll be able to get a real close-up on nature. A fascinating play which is particularly fun for kids to watch and learn.
Unfortunately, I was only equipped with my iPhone when I found this colony. I’ll try to get better photos with my DSLR when I get the chance.