The lofty, tall, vertical blow of a blue whale off southern Sri Lanka. Photo credit Asha de Vos.
Asha de Vos was perched precariously above the deck of the Odyssey, a research vessel in the Indian Ocean. She was trying to climb 80 feet into the crow’s nest, but she had frozen halfway up. She had two choices, the captain said: go up, or come down. So de Vos decided to climb. From her lofty perch, she saw an arresting sight: her first blue whale. The animal was almost as long as the 93-foot Odyssey.
It was 2003, and the ship was on a voyage near Sri Lanka. Later, the researchers came across a group of six blue whales. It shocked de Vos to see them feeding. This went against what the Sri Lankan native had learned during her undergraduate years at the University of St. Andrews in Scotland: that blue whales fed exclusively in polar regions, where waters are rich with nutrients and dense with krill. This was the first time de Vos had heard of them dining in tropical waters. The sighting suggested to her that marine biologists had much to learn about these unique whales.
Since then, de Vos has dedicated her early career to studying Sri Lanka’s native giants. Her research hints that this group of whales might be fragile and threatened. And in a policy coup, her activism has convinced the government of Sri Lanka of the need to alter the routes of ships, which plow into the whales far too often.
“My sense is that this population was never very big, and then it got hammered by illegal Soviet whaling [in the 1960s] and now is even smaller,” says Bernie Tershy, an adjunct professor at UC Santa Cruz, where de Vos is now a postdoctoral scholar. “Asha’s work has tremendous potential to have an impact. I’m really optimistic.”
Sri Lanka’s recent civil war, which raged from 1983 to 2009, made it difficult to study these animals, known as pygmy blue whales. But some distinctions are clear: they are 15 feet smaller than Antarctic blue whales, they breed six months out of sync with their cousins elsewhere, and they call to one another using a unique dialect. This call signature allowed scientists to confirm that Sri Lanka’s blue whales don’t migrate to Antarctica, like other populations; acoustic monitors don’t detect the whales there. Further, de Vos showed that they behave differently. For example, they “fluke up,” or lift their tails high in the air before deep dives, more often than blue whales in other populations.
Scientists most commonly spot the pygmy blue whales along Sri Lanka’s southern coast. Ship traffic between Africa, the Middle East, and Asia all converges there as well. The intense ocean commerce—some of the world’s busiest—must harm the whales, but de Vos doesn’t yet have firm numbers. It’s a hard problem to study because whales hit by ships may drift out to sea or sink. If carcasses do wash up on shore, they are often too decomposed for scientists to identify the cause of death.
Despite these challenges, de Vos thinks it’s clear that ship strikes are a major threat. Data on strandings in California show that for every one whale that is struck by a ship, at least ten are lost at sea. And in Sri Lanka, strandings are common. People send de Vos photographs of stranded whales, and those wrapped around the bows of ships in Sri Lanka’s harbors, and she has seen whale carcasses with obvious injuries from ships floating out in the ocean. She has also witnessed several close calls while observing the animals in the wild. Now, she seeks to prove the impact on pygmy blue whale numbers—and to chart where the collisions occur.
“The ships are like huge bowling balls,” de Vos says. “They just wipe out anything that is in their way.”
To complicate matters, after Sri Lanka’s civil war ended, the government built a new port in the southern coastal city of Hambantota. “When that came up, I immediately knew it would cause a bigger problem for the whales because there would be ships closer to shore,” de Vos says. “Ships are traveling from Hambantota to Colombo, right where the whales are going to be.”
At UCSC’s Coastal Conservation Action Lab, de Vos is now working to attach numbers to her suspicions. She collaborates with Tershy and marine biologist Don Croll on a photo identification system that will help her estimate how many blue whales call Sri Lanka’s waters home. She also has joined with scientists from the National Oceanic and Atmospheric Administration to build habitat models that will allow her to predict where the whales usually linger. The work is based on successful research by biologists that compelled federal officials to shift shipping lanes off the coast of California in 2013. The new models will show how the shipping lanes overlap with blue whale habitat—and suggest how to minimize collisions.
“Asha approached us with a problem that was tangible and had a real solution,” says Croll. “Most whales are being threatened by things like climate change, where it’s difficult to identify specific conservation actions that can make a difference. But Asha can.”
Her work has gotten a lot of media attention, and it seems to have sparked reactions in high places. Her first victory came in 2010, when the fisheries minister stated in a Sri Lankan newspaper that he would not change the shipping lanes because of the blue whales. “A lot of people would have been defeated, but I chose to take a positive spin. It was the first time they’d ever said the words ‘blue whales’ and ‘shipping’ in the same sentence,” de Vos explains. “It means that someone had prompted them to think.”
In every interview de Vos has done since then, she has talked about ship strikes. She shows the photographs people send to her in all of her talks. And in May 2014, it paid off: the fisheries minister announced his intention to move the shipping lanes. Now, de Vos plans to work with the relevant government stakeholders in Sri Lanka to help determine where to place the new lanes and to understand the feasibility of such actions.
It has taken de Vos a long time to earn the respect of officials in Sri Lanka. Not only is she a female Sri Lankan marine scientist, she is the only person in the country who focuses on scientific research related to marine mammals. “I remember when I finished my master’s degree and went back home, and even at that time I was the most qualified for this type of work in the country,” de Vos says. “I’d go to the government meetings and they would ignore me because I was female and not senior enough. I’ll always be too young, and I’ll always be female. Now they’re finally starting to accept me.”
The lack of resources in Sri Lanka has also stalled her work. Even finding a boat can be difficult. Once, visiting researchers from Duke University brought an echosounder to map krill density in the water. She spent months preparing for their visit, even having a special stainless steel mount built for the equipment on the vessel she’d reserved. When she parked the boat after a test drive, she heard a suspicious gurgling sound: the boat was sinking. After losing a few days she managed to find a close replacement, but the team had to use duct tape and bungee cords to secure the expensive device.
During her work, de Vos often gauged the ocean’s salinity and temperature with a conductivity-temperature-depth (CTD) recorder. On big research vessels, scientists lower instruments using a winch. Having no such luxury, de Vos raised and lowered the CTD more than 300 feet each way by hand. Sometimes, she did this at least 50 times a day.
She plans on spending another year at UC Santa Cruz before returning home for good. She hopes to start her own nonprofit organization, devoted to marine research that drives both conservation and educational outreach. She wants to inspire the next generation of marine biologists globally, but specifically in the developing world. “That’s where my heart is,” de Vos says. “The only reason I would live somewhere else is to scour this information together and take it back home. I want to develop the field in Sri Lanka. We have a lot of talented and passionate students, not just there but throughout the developing world, and people tend to overlook them.”
In 2003, Asha de Vos climbed 80 feet above a ship’s deck and saw her first blue whale. She has been climbing steadily ever since.
– Sara Cannon, an undergraduate at UC Santa Cruz majoring in marine biology, wrote this story in spring 2014 for BIOE 188: Introduction to Science Writing.