As the Atlantic Ocean warms, fisheries scramble to adapt

Cape Cod got its name for the abundance of cod off the shores of Massachusetts, but it wouldn't be an apt namesake today.

First, the once populous fish was decimated by decades of Atlantic overfishing, which was also felt acutely in Newfoundland. Now, climate change is further complicating that, as different fish species show up in Gulf of Maine waters warming more quickly than the global average. 

"Changes are hard on everybody, and they're hard on communities as well. And so Atlantic cod presents sort of the cultural, iconic challenges for New England," said Jon Hare, director of scientific programs for National Oceanic and Atmospheric Administration (NOAA) Fisheries in Woods Hole, Mass. 

There are three main factors contributing to the rapid rate of warming in the northwest Atlantic, according to Hare:

Ocean surface temperatures have increased by 1.5 degrees Celsius since the turn of the 20th century, with parts of the North Atlantic warming more quickly than the global average. The Gulf of Maine, between Cape Cod and Nova Scotia, is a hot spot. 

According to nearly 60 years of monitoring from NOAA Fisheries, fish are feeling the impacts, responding in ways that change the composition of what species are found where and when. Off of Cape Cod, that looks like species such as black sea bass moving in and lobster moving on.

Some fishery workers say the fish are moving at a faster rate than regulations about what can be fished, where and in what quantities. This directly affects their livelihoods, and in turn what does — or does not — make it onto people's dinner plates. 

Eric Hesse, now 58, started fishing off the shores of Cape Cod in the mid-1980s for cod, haddock, and bluefin tuna. Recently, he's noticed the summer season for bluefin tuna is starting earlier. 

"I've been telling people that June is the new July," said Hesse.

Hesse recalls he could still make a decent living when he first started fishing, even though the population of cod had already declined. Now, he worries changes in the warming ocean may not allow for the species to rebound. 

"I'm not here to say that I'm the victim of climate change, but I think we've put ourselves in a bad position," said Hesse. 

Hesse now makes up the shortfall in his income by using his fishing gear to help research organizations like NOAA monitor fish stocks in the Atlantic. Where he used to see cod before, now he sees spiny dogfish, a small shark he said is mostly exported to Europe because the market hasn't taken off in New England.

"They just haven't embraced the idea of using a species that is abundant here and fresh and just doesn't have the same kind of flesh as a flaky white cod," he said.

Ocean warming means one species might expand its range, another could contract and another might shift to a different area altogether. Some species respond to the warming ocean by becoming more abundant, while others are less productive.