The audience packed the room at the Fishermen’s Forum for a presentation on the status of North Atlantic right whales. Mark Baumgartner from the Woods Hole Oceanographic Institute opened the presentation with a review of right whale population numbers.
The Atlantic Large Whale Take Reduction Team (ALWTRT) also is taking steps to evaluate how best to protect right whales. Currently there are numerous regulations in place to protect the whales including a seasonal closure in Massachusetts. The ALWTRT has set up two subgroups, one to study the possibility of using 1,700-pound-strength rope and the other to evaluate the technical, functional, and economic feasibility of ropeless fishing techniques in the lobster fishery. Amy Knowlton, a marine biologist at the New England Aquarium in Boston, spoke about the impact that stronger rope has had on right whales. Copolymer rope that came into use in the mid-1990s is much stronger than earlier types of rope. She noted that according to the photo catalogue on right whales maintained by the Aquarium, 85% of all identified right whales show signs of being entangled in fishing gear. “Those injuries have become more severe and the entanglements have become more complex and lethal,” she said. Knowlton studied 70 cases of fishing gear entanglement by four species of whales. She found two patterns: smaller whales, such as minkes, and right whale calves up to two years old could break free of ropes with less than 1,700 pound breaking strength. She also found that with more traps on the bottom, a whale could break a 1,700-pound line more quickly than a line with fewer traps on it. She also referenced a “Chinese finger,” a section of hollow braided rope spliced into existing rope, that could act as a weak link and break if a whale became entangled. The technique is now being tested in Massachusetts by fishermen seeking access to the closure area. Ropeless fishing, Baumgartner said, removes the endline and buoy from a trap, thus keeping a whale from entanglement. The technology sinks the surface system to the bottom and uses a modem, like those found in smartphones, to retrieve the gear. The modem on the boat triggers a mechanism on the trap that releases the rope and buoy which then float to the surface. Another technique is to release a float, which would lift the trap itself to the surface. Acoustic devices on the boats and traps would allow fishermen to communicate with their traps and locate them as well as feed information to their cell phones. For example, if the current moved a trap and another boat passed over it and picked up its signal, a text would be sent to the owner’s cell phone providing the trap’s location. The audience did not respond well to the notion of ropeless fishing. Many expressed a sense that ropeless lobster fishing was ridiculous in such a large fishery as Maine’s as well as a needless expense to lobstermen.
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