Ocean robots take pulse of planet by measuring microbes
It looks like a trashcan bobbing in the waters off the California coast. But it’s hardly garbage. In fact, it may play a key role in monitoring the health of our oceans.
The vital signs? The health of the seas’ smallest residents — phytoplankton.
From diatoms encased in glass to dinoflagellates that can cause toxic algae blooms, phytoplankton are a diverse group of algae that live in the ocean. They serve as the base of the ocean food chain and are responsible for cycling nutrients in the water and producing oxygen through photosynthesis.
“One out of every two breaths of oxygen that you take is coming from plants in the ocean, and most of the time people don’t think about them because they’re microscopic,” said Bethany Kolody, a graduate student researcher at the Scripps Institution of Oceanography in San Diego.
But the diversity of phytoplankton makes it difficult to predict how they will respond to changes in the ocean — especially those due to global warming — and how their reactions will affect ocean health as a whole.
An influx of nutrients into a particular area can fuel a massive algae growth. Changing water temperatures can shift the distribution of available food sources. Patches of the sea can absorb carbon dioxide and acidify.
All of these changes require phytoplankton to respond to new pressures. Unfortunately, eavesdropping on them can be a bit of a challenge.
If researchers don’t happen to have an expedition planned when one of these ocean events occurs, it might as well not have happened, said Andrew Allen, a microbial oceanographer and ecologist at Scripps.
“You really need to be at the right place at the right time to sample,” he said.
One solution may come in the form of “a lab in a can,” said molecular biologist Chris Scholin, president and chief executive of the Monterey Bay Aquarium Research Institute (MBARI). It’s an ocean-going robot that brings the tools of a molecular biology lab to the sea.
This robot, called the Environmental Sample Processor — or ESP for short — was developed about 15 years ago by Scholin and his team at MBARI.
Scholin came up with the idea while he was studying harmful algae blooms in the Gulf of Maine.
“I was just blown away by how people would go to sea and put instruments in the water, and they could tell you everything that was going on,” he said. “But when it came time to actually count the toxic algae for public health purposes and research, it would take us days.”