BAR HARBOR — To cut down the chances of whale entanglement with fishing gear, researchers and developers are testing technology that would eliminate the need for the vertical lines that run between lobster traps on the seafloor and buoys bobbing on the surface.

Lobstermen are facing tighter restrictions to help with the recovery of the endangered North Atlantic right whales and so-called “ropeless” fishing is seen as one of the potential ways to ease that burden.

Traditionally, lobstermen have a buoy on the surface to mark their string of traps on the ocean floor, and they are connected by a vertical line. Ropeless fishing would ditch the persistent vertical line that sits in the water.

“We’re in a place where we’re still testing and doing research to see how much this can be part of the solution,” said Zack Klyver, the science director at Blue Planet Strategies. With his company, Klyver is working with gillnet fishermen and is looking for Maine lobstermen who might be interested in testing out the technology. “We’re actively looking for lobster fishermen that want to be pioneers, that want to see if this can be part of the solution.”

There are currently two main types of ropeless fishing. One is a trap-like cage that has a rope stowed inside. A lobsterman can trigger the release of the buoy, bringing the rope to the surface. The second type includes a lift bag in the trap. It blows up like a balloon on demand, bringing the trap along with it.

EdgeTech, a Massachusetts company, has been making acoustic release devices for other industries for years and applied that technology to the trap fishery. The company has developed a cage that acts as an additional trap on a line. A lobsterman can call up the cage with an app and grab the released buoy. From there, it’s basically the same fishing process that’s currently in place, said Rob Morris, a product line sales engineer with EdgeTech.

With the app, fishermen could also find their traps, as well as share the location information with other fishermen and regulators, making enforcement and data collection easier, he said.

These tests come as the population of the right whales has fallen to fewer than 400. Federal officials say that entanglements are a leading cause of death for right whales, a critically endangered whale that migrates along the east coast. More than 80 percent of right whales carry scars that indicate that they have been entangled in fishing lines and nearly 60 percent of those are entangled more than once. The National Oceanic and Atmospheric Administration says that in recent years, most documented fishing gear entanglements of large whales that result in serious injury and mortality come from trap/pot gear.

The agency’s potential new rules for the trap fishery could include closures for fishermen who use the vertical lines, but lobstermen could continue to fish if they use ropeless systems.

Most of the testing is currently being done in Massachusetts and there’s been resistance to the idea in Maine. Lobstermen here have said that they are not to blame for the decline in the whale population and have been skeptical of the technology, with concerns about the cost and functionality.

Klyver said there could be some advantages to using these types of systems.

“This potentially could make the lobster fishery more efficient,” he said. “Now, when lobster is $7 a pound and you’re out there trying to pull as many traps as you can to get as much lobster as possible, that means a lot.”

While pulling one trap, captains could also call up other traps so they are ready and waiting when they get there. He also said that, with eliminating the vertical lines, there could also be fewer lines tangled.

Lobstermen would be able to find any lost traps with the tracker apps included with the ropeless systems. A Massachusetts fisherman was able to use the acoustic signal technology and found his trap more than a mile away.

“When you add technology, there could be a lot of additional benefits that could really help this fishery and overcome this wicked conundrum that we’re in with having very little good options when we’re thinking about how to save right whales and save fishermen,” Klyver said.

Toby Stephenson, the captain of the RV Osprey at the College of the Atlantic has seen the ropeless technology deployed off the school’s boat in a research capacity and said they are reliable.

“The last 10-15 years, the technology has improved significantly,” he said. “The technology is just as solid as technology gets.”

The acoustic technology used to call up the traps has been used in scientific research for decades and it has been shown that it can be done in fishing as well, said Sean Brilliant, a wildlife biologist at the Canadian Wildlife Federation and a member of the Ropeless Consortium.

Whether it can be used in every harbor remains to be seen, he said, and the technology is still not available on a wide enough scale where whole fisheries could convert.

The lack of buoys marking the location of traps could make it hard for other fishermen to set their gear, unless they all get on board with the apps, which are still in their early stages.

“In general, this gear is not ready for primetime,” Brilliant said.

Stephenson expected there to be resistance among the lobstermen and he also had concerns about the user interface.

“Right now, they’re catching lots of lobsters and what they have is working just fine for them,” he said. “Why would they want to change it?”

Brilliant noted that this technology wasn’t only being looked at for right whales but for other whales too. It’s also a global problem as well, not just something specific to the northeast.

Though it still has an uphill climb, not that long ago, ropeless wasn’t even part of the conversation, Brilliant said. To him, that was an indication of progress.

“Up until a few years ago, it was science fiction,” he said. “We’ve come a long way already.”