It is always a joy to find large and amazing caterpillars of Hawk-moths, especially if you have been searching for them. In case of the Poplar Hawk-moth (Laothoe populi) it may require a bit more of searching since these “hornworms” are masters in disguise. The feeling that hits you after browsing through bushes and finally finding what you’ve been looking for: priceless.
I’ve been lucky this summer and found a couple lime-green caterpillars of the Poplar Hawk-moth. Here’s some footage. Scroll further down for tips and photos showing how to track them down.
How to find caterpillars
There’s a couple simple tips that may be of help to you. Assuming the time and general habitat is right start focusing on following:
- Browse through young trees, or rather bushes, of aspen. Even though I’ve been browsing through low hanging branches of old trees I’ve mostly got lucky on narrow bushes. The height may vary between 60cm up to 2 meters. This also makes the search more comfortable, since caterpillars often feed on the height of your eyes or lower.
- Focus on feeding traces. Caterpillars of Hawk-moths require a lot of food to grow. This results in often easily recognizable feeding traces on the plants that host a caterpillar. On aspen, the primary food plant of this species, caterpillars eat entire leafs leaving only the stalks left. Such “naked” stalks can be spotted from a good distance. Once such traces are found, focus on browsing through the branch or bush with more care.
The footage below (and above) hopefully shows what to look for. Have a good look at the following photos. You can find a caterpillar on four of them.