A Raspberry Pi-Powered Insect Tracker Provides New Insight Into Daytime Activity

A team of researchers have developed a new tool for studying insect activity in-the-field — by modifying open source software originally intended for home security systems, running on a Raspberry Pi single-board computer.

"Most of what we know regarding insect behavior is from species that are active during the day," explains Akito Kawahara, curator of the McGuire Center for Lepidoptera and Biodiversity at the Florida Museum of Natural History. "We study butterflies, bees and ants because we can see them, but there are hundreds of thousands of nocturnal insects out there, all of which have been nearly impossible to track until now."

Kawahara is co-author of a paper detailing a new device designed to replace the traditional "insect curtain" — literally, a curtain that is used at night to attract and trap insects for study. Designed to operate at a low cost yet be portable for field use, the portable locomotion activity monitor (pLAM) is built from an Arducam camera module with switchable infrared filter, lights, a folding mesh cage, and a Raspberry Pi running the Motion software — originally created to act as a motion-sensing camera for home security.

Using Motion as base, the team was able to put together a Python-based processing pipeline designed to capture footage of insects, log it, and analyze it with image and text file outputs. Powered by a USB battery pack, the entire system is fully portable — which PhD student Yash Sondhi, first author of the paper, and Kawahara proved with a Costa Rican field trip to collect data on 15 species of moths.

"It was so cool to see the different activity patterns," says Sondhi. "Not everything is as black and white as we think. Now, we can predict and better understand what’s driving when insects fly. The goal is to quantify when they are active and then associate that with their traits — for example, if a moth is dull-colored, beige, does that mean it’s strictly nocturnal?"

More information on the project is available on the Florida Museum website, while a paper on the pLAM has been published under open-access terms in the journal Methods in Ecology and Evolution.