UV Caterpillars!
I talked a bit about my field work already, particularly about how I find adult moths... but what about caterpillars? Let's talk about finding those!
When I am looking for caterpillars at night, I always have a flashlight (any regular old one will do), and my UV flashlight. The regular flashlight stays off until I find something with the UV flashlight and need to identify it.
Why do I use a UV flashlight? Well, it makes caterpillars glow! If you watched the campaign video, you can see a video of this in action. It looks pretty cool! You can see another example below.
Why do caterpillars glow like this? Well, basically, there are certain pigments in the caterpillars skin that get "excited" when the UV light hits them, and thus causes them to fluoresce.
Many species of caterpillar fluoresce, and it really makes finding them a lot easier. This might be considered cheating to some, but it's really the best way to get a good idea of what is in the area when conducting surveys.
I use the UV flashlights to efficiently scan strands of hostplant in particular areas of my field sites to see if there are larvae present. If there are, I collect them, record the instar, hostplant, and location, and then bring them back to the lab for rearing.
Finding these caterpillars is a lot easier at night, even without the UV flashlight. Many species of Sphingidae (and other Lepidoptera) descend from the hostplant during the day and hide in the grass below, or on stems hidden among dense foliage. This can make locating them tricky.
Perhaps the biggest benefit to using the UV flashlight is the ability to find caterpillars of every instar with ease. With my work, it is often important to collect the younger instars to really observe their growth. This can be tricky to do, as younger larvae are more well hidden.
Thank you for reading this! I hope you found it informative. If you have questions, please post them below and I'll be sure to respond!
If you have already donated to my campaign, thank you very much! I sincerely appreciate your support. My research is not possible without your help! If you haven't yet, there's still plenty of time! If you're unable to support, please share this with your friends and on social media.
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