In 2004, a humpback whale was spotted entangled in fishing gear in Banderas Bay, a small bight on the Pacific Coast of Mexico in which the resort town of Puerto Vallarta nestles.
This area is home for Astrid Frisch-Jordán, the operations manager for Ecotours de Mexico and a professional whale watcher. Concerned townspeople were soon calling her about the trapped animal.
“The first day, we were like: ‘Oh, that’s very bad, but we cannot attend, we are not experts’,” she recalls.
As the hours ticked by, the community’s urge to act grew. “By the second day, we said: ‘Well, we have to do whatever we can’. And then [on] the third day, we went out [to] sea with just garden tools and our knowledge about whales.”
So began seven dangerous hours of her and several other like-minded locals attempting to cut the animal free with equipment designed for trimming plants. Meanwhile, other whales were trying to intimidate them into leaving.
“It was quite dangerous. But the whale was fully released and we were all okay,” says Frisch-Jordán, who is also the head researcher for an NGO called Ecology and Conservation of Whales (Ecobac). “It changed my life completely.”
The event led to the formation of the Mexican Whale Disentanglement Network (Raben), which this year celebrates 20 years of operation and the successful disentanglement of 66 whales from gillnets, lobster pots and other fishing gear.
From its early days in Banderas Bay, Raben has grown to encompass 15 teams and 180 members. Its growth has coincided with a surge in reports of tangled whales, from less than 10 a year, to 37 by 2021; Frisch-Jordán co-authored a paper published in February that details this rise. According to experts consulted by Dialogue Earth, the surge parallels a global increase. This has likely been driven by an outreach effort encouraging people to report, an increase in entanglements as fishers expand their activities, and the recovery of North Pacific whale populations after the end of industrial hunting.
Freeing the bound
Being tangled in a net or other fishing gear is a horrible experience for marine mammals. Held below the surface, smaller animals can drown, and while larger creatures may be able to swim away, injury is common. Ropes can cut into flesh and slow whales down or force their bodies into awkward positions that inhibit feeding.
Whales are hugely powerful and can drag fishing gear that would be impossible for humans to even lift – one whale attended by a Raben team off Mexico’s coast was tangled in a cod pot from Dutch Harbor in Alaska weighing over 200kg, Frisch-Jordán’s paper notes. The whale may have dragged the load for more than 4,000 nautical miles.
Freeing whales from entanglements is not easy. Typically, teams approach in small boats and try to attach their own line to whatever fishing gear is entangling the animal. If this is successful, buoys are attached to the line, which slow the whale down and keep it at the surface, allowing crucial time to try and cut away the entangled gear with special knives.
The risk for would-be rescuers is becoming entangled in the very fishing gear they are trying to cut loose. Members of disentanglement teams have been dragged under the water and died in such cases; some rescuers have also died from the impact of marine animals hitting them.
“Training people to do this is an enormous responsibility,” says Scott Landry, who directs the Marine Animal Entanglement Response programme at the Center for Coastal Studies in the US. “We live in fear that people are going to be injured doing this work.
“These are large animals. These are fast-moving, messy operations, and we’re dealing with an animal that has no idea we are trying to help them,” adds Landry, who is also a member of the International Whaling Commission (IWC)’s Expert Advisory Panel on Entanglement Response. “I would say they are very unpredictable – and you’re getting them at the worst moment of their lives.”
The techniques used by Landry, Frisch-Jordán and others around the world have their roots in whaling, mankind’s rather less friendly interaction with the world’s largest mammals. Whalers would harpoon them and attach barrels to keep the animals from disappearing below the waves: this history has simultaneously led to today’s dangerously low populations of some species, and provided disentanglers with the tools to help.
The right whale problem
In the 18th and 19th centuries, North Atlantic right whales were savagely hunted. The whales’ name comes from the notion that these animals – which can exceed 15 metres in length and 60 tonnes in weight – were the “right” ones to hunt, as they were slow-moving and would float once dead.
The pre-whaling population, estimated at 21,000, was harpooned down to a few hundred by the end of the 1800s.
Any threat to a right whale that will increase its mortality risk, or increase ill health from sub-lethal entanglement, will directly affect the chances of the species going extinctMichael Moore, Woods Hole Oceanographic Institution’s Marine Mammal Center
After growing steadily from less than 300 in the early 1990s to number nearly 500 at the start of the 2010s, the North Atlantic right whale population has now contracted to approximately 350. The chief cause is people: the whales are most commonly struck by ships plying the eastern seaboard of the US, or tangled in Atlantic fishing gear.
Researchers who have studied scars on these animals believe over 80% of North Atlantic right whales have been entangled at least once.
“Any threat to a right whale that will increase its mortality risk, or increase ill health from sub-lethal entanglement, will directly affect the chances of the species going extinct,” says Michael Moore, who directs the Woods Hole Oceanographic Institution’s Marine Mammal Center in the US.
Moore cites estimates that around 70 reproducing females are left.
Becoming trapped in fishing gear can so sicken whales that they are no longer able to reproduce. Some entangled right whales become so emaciated that they sink rather than float when dead; this is normally only seen in exhausted females after carrying young and giving birth. “Essentially they are dead whales swimming,” says Moore.
Taking techniques around the world
North Atlantic right whales are not the only marine mammals on the brink.
David Mattila, who coordinates the IWC’s expert panel and the Global Whale Entanglement Response Network, is also concerned about the impacts of entanglement on Arabian Sea humpback whales, Chilean right whales and Sea of Okhotsk bowhead whales. Entanglement might also harm the western grey whale, but the animal is so rare Mattila cannot be sure it still exists.
“These are populations of large whales that are very critically endangered, and they are exposed to entanglement,” Mattila tells Dialogue Earth. He adds that these are populations for which the death of even one whale due to entanglement could potentially be a major conservation issue.
Mattila was involved in the development of professional disentanglement efforts in the 1980s. This year, he celebrates the 40th anniversary of his first rescue – a female humpback trapped in a gill net near Provincetown, north-western US.
“Now we know, basically, it happens anywhere in the world you have whales and man-made rope or net in the water,” says Mattila.
Growing concerns and rising reports of entanglements triggered the IWC to convene a special meeting on the topic in 2010, which recommended capacity-building for rescues around the world, alongside prevention. Mattila estimates that, to date, around 1,300 people from 36 countries have been trained by this IWC initiative.
Rope: A problem for fishers, and for humanity
For every whale reported to a rescue network, many more are entangled and die unseen. The real solution, say those involved, should be preventing whales from encountering rope in the first place.
Modern fishing gear ropes are made of various forms of plastic, and manufacturing changes in the 1990s significantly increased their strength. Using weaker rope – either by cutting some strands or manufacturing weaker rope in the first place – has been suggested as a way of saving whales, as has closing areas where whales might come into contact with boats, such as shipping lanes and fishing areas.
Some fishers are also experimenting with marine-mammal-friendly, rope-free systems. For example, typical lobster fishing entails a lobster pot on the sea floor, permanently connected by a rope to a marker buoy at the surface. Rope-free systems use sunk gear with no permanent rope: instead, a lobster catch triggers the pot to release a float, which rises to the surface and signals the gear is ready for retrieval.
However, these solutions all stand to increase the price paid by consumers. To date, society has not been willing to stomach that price, says Moore.
Current industrial fishing methods are predominantly designed to prioritise the catch. Until this paradigm shifts, teams like Frisch-Jordán’s will continue receiving calls about whales entangled in the vast array of equipment that fishers have created to extract food from the seas.
Sometimes, if it is too dark, too dangerous, or a whale is too injured, disentanglement teams cannot help. “The hardest part is when we cannot rescue the whale – and that, of course, happens a lot,” says Frisch-Jordán.
“But when you have a strong whale in perfect shape, and you just set it free, that for me is magical.”
