Marty Odlin, who grew up and lives on the Maine coast, remembers what the ocean used to be like. But now, he said, “It’s like a desert and just within my lifetime.” In the last few years, he said, he has seen lots of sea grass and many other species virtually disappear from the shoreline. 

Odlin, 39, comes from a fishing family and has a passion for the history of the ocean and the coast, both of which have informed his sense of the ocean’s decline, a small part of the catastrophic deletion of marine life over the last several hundred years. Using his training as an engineer, Odlin has decided to try to reverse that decline with his company, Running Tide, which is based in Portland. Using a combination of robotics, sensors and machine learning, he is building an aquaculture operation that is selling oysters now and eventually clams. He is also using that system to grow kelp, with the goal of producing enough of this seaweed to pull carbon dioxide from the atmosphere and permanently sequester it by burying it on the ocean floor, and sell carbon offsets. 

The company also plans to seed oyster reefs and clam beds along the shoreline, and restore kelp forests and sea grass, to help the coastal ecosystem by bringing back biodiversity and improving water quality, among other benefits. Odlin’s plans are one of a number of efforts in the “blue economy,” a term used to describe commercial activity on the oceans, seas and coasts. He and others are trying to prove that ocean conservation, sustainable fishing and carbon sequestration can be good for business, especially as global shipping, aquaculture and the appetite for wild seafood increases around the world. 

Odlin and his team build everything: boats, oyster floats, sensors and more, all with very high sensitivity to their environment. They measure the amount of feed in the water and the growth rate of the various species and send that information into a database that they use to make all sorts of decisions: whether to change the feed, reposition the shellfish floats or make bigger changes about the varieties they’re growing. They also use the hard-won knowledge of commercial fishermen — there are about a dozen on staff — which Odlin said was an advantage. 

The climate crisis demands technological innovations and “hard hats and steel toes,” he said. Dan Watson, the chief executive and co-founder of SafetyNet Technologies, also has recognized the benefits of working alongside industry and demonstrating profitability. His company builds high-tech fishing nets for trawling boats: Attached to the nets are LED lights that flash in various patterns and levels of brightness to signal emergency escape hatches (right-size holes) for those species that fishing boats aren’t trying to catch, known collectively as bycatch. 

Studies have shown that LED lights can significantly reduce the amount of unwanted species that end up in fishing nets. According to the Food and Agriculture Organization of the United Nations, about 9.1 million tons, or just over 10 percent of all of the fish caught every year, are thrown away, with nearly half coming from trawling nets. In an era of overfishing and shifting habitats because of climate change that defy international regulations, reducing the amount of fish or other marine animals that are caught by mistake could have important consequences for the health of various populations as well as ocean biodiversity as a whole, Watson said. 

Any of these projects require a more hands-on approach to saving the ocean and a more deliberate overlap of business and conservation, which have historically been at odds, said Odlin, the founder of Running Tide. “We have to take a more active role in solving the problem that we’re seeing,” he said.