The humpback whale could have been entangled in rope for days. By the time Center for Coastal Studies researchers came across the creature Saturday morning in the Gulf of Maine, it was essentially hog-tied and trapped in a "C" shape.
While disheartening, such a situation isn't an uncommon sight for the center's Marine Animal Entanglement Response program. But this particular whale had company: a 15-foot white shark lurked nearby. The predator had already chomped through the trapped creature's blubber, biting the whale near its ribs.
In the days after the daring rescue mission, researchers are now reviewing whether they need to adjust for a new reality of rescuing entangled whales in the midst of deadly predators. Sharks killing entangled whales has been an ongoing issue in Australia, Landry said, and it could be an emerging problem in Atlantic waters.
"We've been doing this since 1984, and this is the first time, in our knowledge, that we've had a white shark around us," said the program's director Scott Landry. "When we saw it, we were extremely alarmed. It was a very big shark, 15 feet long."
Untangling a giant, wild whale can be dangerous without sharks around -- that's why rescuers never get in the water with the animals. This particular 35-feet-long whale was tied up by rope from its mouth to tail. "The whale was immobile and it's got a very large shark that's already attacked it, and there's nothing the whale can do," Landry said.
That rope had cut the whale, too. "Obviously the whale bleeds from that," Landry said. "I wouldn't be surprised if that's how the shark found the whale in the first place."
Rescuers aboard a vessel typically get on a smaller, inflatable boat to get closer to whales and cut them free from rope. But the massive shark prevented them from doing that on Saturday. So they used other tools to cut the rope from the whale's mouth from afar.
Somewhat free, the whale could swim more easily. The shark soon scrammed, and after a while, rescuers got on their smaller boat and pulled up to the whale. They used a hook-shaped knife to continue cutting rope from the whale's tail. Once all the rope had been cut, the whale quickly swam away, which is a good sign, Landry said. The whole process took about three hours.
White sharks are more likely to attack young or vulnerable humpbacks, rather than full grown, healthy adults.
The humpbacks that swim in the Atlantic are considered endangered, with about 1,000 coming from the Caribbean to the Gulf of Maine every year to feed, Landry said.
"When you look at that, it's a very small number, so any mortality beyond a natural mortality is not good for the population," Landry said. "We believe entanglements are definitely one of the leading causes of unnatural death."
Whales get entangled in active fishing gear, which is often set up for days or weeks for catches. They can sometimes disentangle themselves; researchers find traces of past entanglements via the scars on animals' bodies. Landry estimates that 10 to 12 percent of humpback whales get entangled every year.
Mariners have tried to untangle whales before, which can be dangerous; one was even killed, Landry said. People coming across entangled whales should alert the Coast Guard or other authorities, he cautioned.
Some have experimented with altering fishing technology to help reduce the number of entanglements, and there have been recent changes to federal fishing regulations to try to fix the problem as well. But Landry said that while some members of the public may blame fishermen for the issue, "I personally believe that anger is misplaced... All of this fishing is for a reason: everyone is eating seafood."
"There's nothing nefarious going on; the fisherman aren't trying to do this," Landry said. "They don't want this to happen, but there's not really a great way for us to stop it from happening."