There are a lot of haddock in the Gulf of Maine. The same isn’t true of cod.

The hitch: The two species swim close together.

John Annala, the Gulf of Maine Research Institute’s chief scientific officer, said his institute worked to find out whether it’s possible to catch haddock without catching cod. With some study, they determined that when cod get tired, they swim down. “Haddock swim up,” said Annala.

They partnered with Portland fisherman Jim Odlin, got funding from the National Marine Fisheries Service and tested a trawling net with an opening on the bottom. The theory: When the cod became tired while swimming trapped in the trawling net, they would head down and out the hole.

It worked – but only at exactly three feet off the ocean floor, Odlin said.

“The next step is for that technology to be run through the regulatory process,” said GMRI President Don Perkins. “It’s a cumbersome, complicated process.”

– Kathryn Skelton