Since the HMS Challenger voyage in the late 1800s, expeditions to the farthest reaches of the ocean have provided the backbone of knowledge about marine science. In the wake of an ever growing list of aquatic issues like ocean acidification, sea level rise and coral bleaching, the real challenge for oceanographers is keeping up with understanding the effects of a changing climate. With some newly developed technology however, there’s now a team of robots able to lend a helping hand.

These robots are called Environmental Sample Processors, or ESPs, and they look like R2-D2 in swim floaties. Once set free in the ocean they take biological samples, perform lab experiments in situ, and can ping results back to land via satellite. Rather than outsourcing the exploratory science of oceanography to robots, ESPs are expanding the reach and scope of where scientists are able to investigate.

The ESP is the product of over 2 decades of work led by biological oceanographer Dr. Christopher Scholin, president and CEO of the Monterey Bay Aquarium Research Institute (MBARI). The big hurdle with this project was taking molecular experiments that can be challenging for trained human researchers on land, like detecting trace amounts of chemicals or the quantification of specific genes from microbes, robotically optimizing and shrinking them down to fit in a water tight barrel. In the end, Dr. Scholin and his team succeeded in fitting a lab’s worth of equipment into a vessel the size of a 50 gallon oil drum that was capable of surviving the high seas. 

When still in its early stages of development, these robotic samplers were used by Dr. Elizabeth Ottesen, now an assistant professor of microbiology at the University of Georgia and author of a recent review on ESPs, to tap into the inner workings of marine phytoplankton, microscopic plants responsible for a whopping half of the total primary productivity on the planet, and the organisms that rely on them.

The inner workings of an ESP. Credit: MBARI with thanks to Dr. Jim Birch

Ottesen and her team studied microbial communities in the North Pacific Ocean with a sampling frequency that had never been achieved before. With these high frequency samples, Dr. Ottesen and her team uncovered the graceful choreography in gene expression between photosynthetic and non-photosynthetic microorganisms, patterns that were controlled by the sun and reminiscent of the undulating waves in the environment those microbes called home. This data yielded a peek into the cross-species interactions that underpin ocean ecosystems.

Despite the fact that the ESP enabled some groundbreaking discoveries, these robots weren’t quite ready to set sail on their own. “Truth be told, we followed it with a ship the whole time,” Dr. Ottesen admits. An understandable decision considering the ESP is a half million dollar robot dangling precipitously from Styrofoam floaty in the middle of the ocean. Since this study, however, the ESP team at MBARI have improved technology by leaps and bounds, and these robots are about to embark on solo voyages.

The push to get ecogenomic sampling robots in the water is spearheaded by a division of MBARI called the SURF Center, standing for Sensors: Underwater Research of the Future, which has Dr. Birch at the helm as director. “The ocean is moving,” says Dr. Birch. “So how can you figure out what’s going on if it’s always changing and your sitting still?” The ESP used in previous research was moored to a buoy and subjected to the ebb and flow of the currents. Dr. Birch and the SURF team are developing motile ESPs that could follow a patch of water over time or sample the deep ocean and return to surface. Even without motility, Dr. Ottesen and her team made startling discoveries with the ESP. “If you can couple that instrument with the smarts of an autonomous underwater vehicle, you suddenly have an incredibly powerful tool,” that can follow organisms through space and time, says Dr. Birch. “We are going to transform oceanography when this thing is up.”

Divers test the pressure housing of the ESP. Credit: MBARI with thanks to Dr. Jim Birch

After motile ESPs are let loose, the next innovations to come are equally exciting. Dr. Birch predicts that one day ESPs might be able to perform next generation DNA and RNA sequencing on the fly. There are also more practical applications in store for these machines. This August, an ESP is being deployed in Lake Erie, just outside the intake pipe for the City of Toledo’s drinking water.

For the past two summers, a harmful algae called Microcystis has bloomed in the lake and produced a toxin that rendered over 500,000 people with no safe drinking water. Standing sentinel in Lake Erie, the ESP will take be able to take water samples, measure the abundance of Microsystis and the quantity of toxin. Because these results are beamed to monitoring centers in near real time, water officials in Toledo will have the unprecedented ability to keep tabs on the safety of drinking water without ever leaving land.

Deployments of ESPs hold great promise for public health. In addition to their new role in monitoring drinking water, Dr. Ottesen envisions ESPs keeping watch over recreational beaches, keeping a lookout for fecal bacteria or harmful algal blooms. The goal is to get the word out to officials “before they happen, rather than letting you know the day after that it wasn’t a good day to swim at the beach,” says Dr. Ottesen.

In the current technological revolution, robots are taking over human jobs in factories, shipping warehouses and even in customer service, as ESP technology advances could autonomous marine robots eliminate the need for research expeditions, thus land locking oceanographers? Dr. Birch said that’s not likely to happen. ESPs will enable access to harder to reach locales without worrying as much about bad weather or boat availability. “There will always be a reason to send people out there,” said Dr. Birch. “It’s not land locking oceanography as much as transforming oceanography into better data and better science, which help us answer the bigger questions.” Dr. Ottesen agrees, “I’d like to think we’re just expanding our range. It makes it easier to do more, to fill in the gaps and see what we’re missing.”

Overall, these little floating robots could usher in a revolution for marine microbiology. Though small, the microorganisms that ESPs enable access to could provide untapped insight into the changing ocean. The trick is simply getting out there to take the samples, but with ESPs, Dr. Ottesen says “we can get our finger on the pulse of the ocean.”