Backed by Lasers, Robotic Rovers Defend the Desert Tortoise
One of the Guardian Angel rovers meets a tortoise. Image: Tim Shields


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Backed by Lasers, Robotic Rovers Defend the Desert Tortoise

With an app and user-controlled rovers, Tim Shields is gamifying conservation—and it's awesome.

The desert tortoise is a small, humble species that ambles across the Mojave and Sonoran deserts in southern California. Once abundant, the desert tortoise is being driven towards extinction by increasing urbanization.

Leading that charge is the wily raven. Ravens are natural predators of the desert tortoise, and tear into the shells of helpless juvenile tortoises. In the past, the scarcity of food and limited habitat kept the ravens in check. But as people moved into the tortoise's territory, we brought garbage for ravens to scavenge and built structures for them to roost on. Their population exploded.


"For 32 years I watched ravens destroy my favorite species and I couldn't do anything about it," said Tim Shields, who has spent his life studying desert tortoises. In 1996, thanks in part to research by Shields, the desert tortoise was declared threatened. According to Shields, the booming raven population now poses an existential threat to the future of the desert tortoise. After three decades documenting their decline, he's ready to fight back.

The front-line defense in his fight against ravens is the Guardian Angel rover. Guardian Angel is a mobile, internet-controlled, RC buggy outfitted with a user-controllable camera for livestreaming video. Guardian Angel is roughly the same size and speed as the tortoises. It is designed to minimize disruption to the tortoises, but the ravens hate it.

"If we put devices out there, looking at the planet, people will fall in love"

For Shields, this project is all about working with the ravens' intelligence and building tools that alter their behavior. Ravens are smart, but they're also extremely conservative and, according to Shields, they hate these rovers. According to Shields, just the presence of the Guardian Angel is enough to keep the ravens at a distance, at least for now.

After a successful Kickstarter campaign last year, Shields and his team at Hardshell Labs have been hard at work perfecting their machine. They recently completed tests of a fully web-controlled unit.


Ravens aren't the only species whose behavior Shields is trying to change. The real target is humans, and that is where the power of an internet-connected rover comes into play. Shields wants to give everyone the ability to discover and explore the desert tortoise's home, while providing protection to the next generation of tortoises.

Ravens may be the most immediate threat, but the desert tortoises are also threatened by habitat loss to new construction and agricultural development, as well as collection for the exotic pet trade. By giving people a new tool to discover and observe the desert tortoise, Shields hopes that his project will enhance other conservation efforts, as well.

It's a mutually beneficial arrangement: Shields gets an army of observers remotely monitoring the tortoises and engaging in active protection, and they get the chance to see a piece of the desert from an entirely new perspective.

"If we put devices out there looking at the planet, people will fall in love," said Shields.

There's another angle to Shields' technology-driven raven defense system. Ravens may hate the Guardian Angel rover, but they abhor lasers. According to Shields, Raven's eyes are particularly sensitive to 532 nanometer green light, and, because of the way that raven eyes focus light, he hypothesizes that they may perceive the laser as a solid beam, rather than a single point. An intelligently guided laser is an extreme negative stimulus for a raven. Shields says that they "learn to run from the dot."


Currently Shields is testing the lasers in the field to determine if they could cause permanent injury to the birds and whether or not the ravens become habituated to them. So far, his tests don't show any evidence of lasting harm to the ravens and the ravens don't stick around long enough to become jaded by the desert light show.

Here's where things get really wild. Because ravens are notoriously smart, the lasers work best when there's an intelligent operator behind it, or, better yet, many intelligent operators to break up any perceived pattern. So Shields decided to make it into a game. In addition to the hardware, Hardshell Labs is also developing an app, Raven Repel, which will allow users to take control of the lasers and chase off ravens. It's gamified conservation. An augmented-reality demo version that overlays simulated ravens on a smartphone camera feed is available for mobile devices.

And, according to Shields, "the ravens are playing the game, too," constantly learning and adapting their behavior. Shields hopes the ravens will earn from the game, and eventually decide that hanging out near the tortoises just isn't worth their time.

Originally envisioned as a comprehensive system, with laser-armed rovers prowling the Mojave, Shields now see these as two complementary programs: laser arrays fixed at specific locations and rovers roaming the desert to defend the tortoises.

Despite the high-technology slant to his program, Shields doesn't see himself as a tech guy, but as a naturalist drawing on whatever tools are available to him to protect the species he loves. It's less about working at the cutting edge and more about finding ways to apply the technology that exists towards solving important conservation and management problems.

For Shields, the ultimate goal of the Guardian Angel rover is to "provide the opportunity for people to perceive the planet they're living on," and save a few tortoises along the way.