A Fitbit for Manta Rays: Sticking with Science to Study a Slippery Species

I spend a lot of time figuring out how animals move through their environment—especially when human activities, like energy and mineral development, overlap with important habitats. But studying ocean giants like the Mobula birostris, or the giant oceanic manta ray, comes with a challenge: the moment they glide out of view, they take their secrets with them.

That’s where biologging technology comes in.

For the past few years, I’ve been working with Georgia Aquarium to refine a new type of biologging device—an IMU (Inertial Measurement Unit) tag. Think of it as a Fitbit for fish, capable of tracking every flap of a manta ray’s fins, its body orientation, depth, and fine-scale movements through the water. This data is crucial for understanding how mantas use areas where BOEM-permitted activities might take place, so we can ensure these endangered animals are properly protected.

But before we could deploy these tags in the wild, we had to solve a surprisingly tricky problem: how do you get a high-tech tracking device to stick to a manta ray?

Blue the Brilliant Bio-logger

Enter Blue, one of Georgia Aquarium’s resident mantas and an unwitting pioneer in marine tech innovation. Georgia Aquarium is the only facility in the U.S. that provides long-term care for manta rays, making it the perfect place to test and refine safe attachment techniques.

The challenge? Manta have smooth skin and a protective mucous layer that makes sticking anything to them a real feat of engineering.

We started with suction cups, which work well on some marine species. No luck. The tags wouldn’t hold. Then we tried Vaseline and Manuka honey, hoping they’d improve the seal. Still no success.

That’s when we turned to prior research. A National Geographic feature on manta tagging experiments mentioned an unusual solution: peanut butter. The logic was sound—it’s sticky, safe for the animals, and easy to apply.

So, we gave it a shot.

Blue the manta swimming with a tag on his head.

And it worked. Kind of.

Peanut butter gave us decent results by far, but a new modified suction cup kept the tags in place for up to four hours—plenty of time to collect some worthwhile behavioral data.

Tech, Conservation, and a Well-Stocked Pantry

It might sound unconventional, but this project is a perfect example of how creative problem-solving fuels good science. By refining this attachment method, we’re developing an open-access tool that can be used by researchers around the world to better understand and protect manta rays, and probably other species too.

At BOEM, my focus is on integrating cutting-edge science into decision-making about ocean energy and resource use. Sometimes, that means working with AI and biologging. Other times, it means experimenting with peanut butter. Science is full of surprises.

I’m incredibly grateful to my colleagues at Georgia Aquarium for their collaboration and to Blue (who I suspect had no idea he was helping advance manta ray conservation). Thanks to their teamwork, we’re one step closer to understanding how these animals move through their environment—and how to keep them safe.

So, the next time you spread peanut butter on your PB&J sandwich, just remember: you might be holding the key to better conservation in your hands.

For more on how Georgia Aquarium’s mantas are helping advance ocean research, check out:

• Georgia Aquarium’s Manta Rays Test New Technology to Help Their Oceanic Counterparts

• Georgia Aquarium Manta Ray Research StoryMap