Low-cost, open-source camera biologgers

In collaboration with Dr. Connor White from University of Virginia and Dr. Mario Espinoza from University of Costa Rica, we developed an open source biologging tag with a camera data logger (4K, 30 FPS), a 3-axis accelerometer and magnetometer, temperature, depth, and light sensors. We designed it specifically for large sharks (>2m length) and leverage off-the-shelf parts in a custom float package. It is equipped with a galvanic timed release, which allows the tag to detach from the shark after a predetermined time interval and float to the surface, where it can be recovered with the onboard VHF and acoustic transmitters. 

 

The assembly time for each tag is approximately 6 hours, but this can be sped up by making several tags in parallel. The only manufacturing processes required to make this tag are 3D printing and epoxy pouring along with a small amount of laser cutting and soldering, making it accessible for most labs. No coding, electronics design, or machining is required, and the entire tag package is around 1/8th the cost of a comparable commercially available tag. We hope to extend our design to make it compatible with other marine animals, such as whales, dolphins, and smaller sharks, and to add additional sensors such as hydrophones. 

 

We tested our bio loggers in September 2025 in Santa Elena Bay, Costa Rica, deploying tags on 4 Pacific nurse sharks and successfully recovering data from each tag. We are currently in the process of writing a short manuscript describing the design and deployment of these tags, along with a full open-source hardware guide to allow others to make their own tag.