A recent lawsuit by the Humane Society of the United States highlights that whales and lobstermen can have a tough time living together. Improved relations will come, in large part, from changes in lobster gear to reduce whale entanglements.

North Atlantic right whales face possible extinction, partly because they sometimes get tangled in the ropes connected to lobster traps and other fishing gear and may eventually die. Ships may kill even more of them.

The number of whales went down to about 300 a few years ago. A local expert on entanglement, Capt. Bob Bowman of Somesville, says that six or seven recent good reproductive years have boosted the whale population to 350 or maybe close to 400. But in the long run breeding can’t keep up with losses through entanglement, he says.

Coexistence worked until the 1970s as long as most lobster fishing was in shallow inshore waters. But with bigger and faster boats, lobstermen now go far offshore and sometimes rig long chains of traps on a single buoy. Floating synthetic line is strong and durable, but it poses an increased hazard to whales.

For some years, Capt. Bowman has worked successfully with a network of lobstermen who would report any whale entanglement and summon expert help in freeing the whale.

That wasn’t enough for the Humane Society of the United States and the Ocean Conservancy, groups that sued the National Marine Fisheries Service last month for not doing enough to stop the entanglements.

NMFS has funded research into various sorts of lobster-trap gear which would minimize fatal entanglements and has offered financial incentives to researchers who develop fishing gear that is less likely to entangle whales. Capt. Bowman says it is too early to tell whether sinking ropes and breakaway connections and panels required in federal waters have reduced whale deaths. Lobstermen worry that sinking rope will break because of the rough ocean bottom and strong tides.

Capt. Bowman says to coexist with the endangered whales, lobstermen must learn to fish without ropes dangling in the ocean. He says it would be possible, through modern electronics, for a lobsterman to sail his boat over a trap, press a button, and have a buoy rise to the surface with a line to haul up the trap.

Whatever new gear is mandated, it will mean additional cost and labor for the lobstermen, costs that could be minimized by federal assistance which has already been proposed by Sen. Olympia Snowe. That is the price that will be paid to continue fishing where whales live.