Humpback whales off New Jersey’s coast, like the young male that washed up dead Friday on a Sea Isle City beach, were taken off the federal endangered species list this month because of rebounding numbers.
But many threats to the whales remain, including boat strikes, entanglement in fishing gear, habitat destruction and harassment by whale watchers, according to the National Oceanic and Atmospheric Administration.
NOAA implements the evolving Atlantic Large Whale Take Reduction Plan, to reduce the number of large whales harmed by fishing gear.
Staff members of the Marine Mammal Stranding Center in Brigantine conducted a necropsy of the juvenile humpback. They saw evidence that entanglement in commercial fishing gear weakened the animal and prevented it from feeding, said Executive Director Bob Schoelkopf.
David Gouveia, NOAA’s Marine Mammal and Sea Turtle Conservation Coordinator for the Greater Atlantic Regional Fisheries Office, said the results are preliminary. Final results aren’t likely for a month or two, he said.
A dead humpback whale washed up Friday afternoon in Sea Isle City near 20th street.
The Atlantic Large Whale Take Reduction Plan is put together by scientists, fishermen and others. It puts restrictions on when and where and how gear can be set, how ropes can be used and their number, and has required weak links that break away when whales pull on them.
“It was established under the Marine Mammal Protection Act,” said Gouveia. “The plan changes the more we learn about entanglements.”
The New Jersey Division of Fish and Wildlife Marine Enforcement Unit patrols offshore, inspecting fishing gear under the plan to make sure it is in compliance, said Department of Environmental Protection spokesman Larry Hajna.
Other components of the plan include research into whale populations and whale behavior, outreach to fishermen and other stakeholders, and a disentanglement program to send trained people to help whales in trouble.
Scott Landry, director of the Marine Animal Entanglement Response Program in Provincetown, Massachusetts, said about 80 percent of humpback and right whales have scars on their bodies from getting entangled at some point in fishing gear.
“Most helped themselves shed the gear on their own,” said Landry. “It has changed what whales look like.”
Gouveia said more blood work, tissue and organ sampling on the Sea Isle whale will determine whether disease was involved and if entanglement played the central role in the creature’s death.
Further tests will look at stress levels in the blood and the amount of scar tissue and blood clotting to determine whether injuries were pre- or post- mortum, said Gouveia, who is based in Gloucester, Massachusetts.
The animal may have gotten entangled, then disentangled, but might have starved to death because of infection or another totally unrelated disease, Gouveia said.
Commercial fishermen are doing what they can to prevent such interactions, said Greg DiDomenico of the Garden State Sea Food Association in Cape May, who is part of the NOAA task force that devises the Atlantic Large Whale Take Reduction Plan.
“These are things no one wants to see happen,” said DiDomenico of entanglements. “It’s never intentional, but still it makes you feel bad.”
But fishing gear isn’t the only threat in the oceans, he stressed, citing a young female sei whale who died in a tributary of the Chesapeake Bay in 2014. It had swallowed a shard of black plastic from a DVD case, and the rigid plastic lacerated its stomach and prevented it from feeding. The whale had also been hit by a ship.
“Vessel strikes are major problem,” DiDomenico said.
A NOAA ship hit a right whale, one of the most endangered animals in the world, in the Stellwagon Banks off Cape Cod in 2009. That animal is believed to have survived.
“I think we’ve done a pretty good job. Everybody has to try,” DiDomenico said of making the gear modifications and following rules on area closings.
The rope lines used by commercial fishermen create a hazard to large species as they feed with their mouths open and swim after fish or copepods (small crustaceans), Gouveia said.
“The whale gets the rope entangled in the mouth and panics and rolls, and becomes like spaghetti on a fork, he said.”
The gear often breaks away, leaving just the rope around the mouth, head and other parts of the body.
The Sea Isle whale had no line left on him, only scars, Schoelkopf said.
“Some of it went through its mouth. There was scarring on either side of the face and wrapped around the back,” Schoelkopf said.
He said there was evidence the scars were healing, so the whale was able to get out of the line before dying.
“But the lack of food left it too weak to hunt,” Schoelkopf said.
Humpbacks feed on tiny crustaceans, plankton and small fish. They can eat up to 3,000 pounds of food per day, according to NOAA.
Schoelkopf said there was also evidence the whale was hit by a ship after death, because the whale’s vertebrae were scattered throughout its body. So the whale was already decomposing when it was hit, he said.
Many parts of the country have organizations with trained rescuers who can disentangle whales when they get caught in fishing gear.
The same day that the dead Sea Isle whale appeared, the Provincetown-based Center for Coastal Studies’ Marine Animal Entanglement Response team freed a young humpback whale entangled in fishing gear off Cape Cod’s Chatham, according to a report by The Associated Press.
Recreational boaters reported the animal, which had a fishing line through its mouth and was dragging heavy gear.
The rescuers used a 30-foot pole and a hook-shaped knife to cut part of the rope near the animal’s mouth, and the whale quickly swam away after it was freed.
A team from the same facility freed an entangled juvenile humpback whale off Point Pleasant Beach, Ocean County, in 2013.
Boaters who spot whales or other marine mammals or sea turtles in trouble can report sightings to NOAA’s hotline at 866-755-NOAA (866-755-6622), and NOAA will arrange help from trained personnel. It is very dangerous to approach an animal without training, according to NOAA.
If boaters do not have a cellphone, they can radio the information to the Coast Guard, which will notify NOAA, Gouveia said.