Blue whales may not know it, but some of the country's brightest scientists are watching out for them.
Funded by a $1.5 million grant from the Benioff Ocean Initiative, a team of marine biologists and technologists from universities and research labs around the United States are developing a system that detects endangered blue whales using acoustic and thermal sensors and sends alerts to nearby boat captains.
The goal is to reduce collisions between big ships and the world's largest animal in California's Santa Barbara Channel, a historical hotspot for encounters that frequently prove fatal for the whales. Scientists believe dozens of blue whales are killed in ship strikes each year off the West Coast, while others are injured.
"We're basically making roadkill of them," says Douglas McCauley, a director of the Benioff Ocean Initiative and a marine biologist at the University of California–Santa Barbara. "The mortality is way more than it ought to be."
The existing whale advisory system for the Santa Barbara Channel, where busy shipping lanes pass through important blue whale feeding grounds, is based on known migratory patterns of the marine mammals combined with information from aerial surveys and observations from whale watching tour boats. Called WhaleWatch, the system gauges roughly when the animals are likely to be present in a given area and produces monthly assessments for risks of collisions within 16-mile grids. Officials use the data to issue recommendations for voluntary ship speed reductions.
"Now, we're hoping to bring that system to a finer resolution of daily updates and a 10km grid," says Elliott Hazen, an assistant adjunct professor of ecology and evolutionary biology at the University of California–Santa Cruz.
But no matter how high-tech an alert system is, it will only be effective if captains of large ships respond by slowing their vessels, either voluntarily or under pain of penalty, experts say.
The new system, which would also tap historical tracking data to generate more accurate information on the whereabouts of whales, is set to come online within two years.
Mark Baumgartner, a marine ecologist at the Woods Hole Oceanographic Institution in Massachusetts, has closely surveyed interactions between ships and highly endangered North Atlantic right whales. He says a mandatory speed limit of 10 knots when the marine mammals are present was imposed in 2008 and resulted in a significant reduction in ship-strike mortality along the east coast of the U.S.
The speed limit applies in several so-called "seasonal management areas" between Florida and Cape Cod. Still, collisions between vessels and right whales remain a profound threat to the species, whose population numbers fewer than 500. Since June of 2017, at least 12 right whales have been found dead in Canada's Gulf of St. Lawrence. A report analyzing the first six deaths found that five of the whales were probably killed by blunt trauma.
Baumgartner helped design a right whale detection system that records underwater tonal sounds and sends a transcript of the recording to an analyst who identifies the distinct songs produced by different whale species. If the analyst identifies a right whale call, she alerts nearby mariners via Twitter, text, and email.
Now Baumgartner is helping adapt his right whale detection system for blue whales.
"We'll need to update the call library to include information about blue whales," he said, noting that the system—which he says has proven very accurate—should be easy to replicate in the Santa Barbara Channel.
Blue whales are very vocal animals whose low frequency calls can travel for hundreds of miles underwater. This means one strategically placed hydrophone will be sufficient to detect the calls of any whales passing through the channel, according to Ana Sirovic, a marine bio-acoustician with the University of California–San Diego's Scripps Institution of Oceanography and one of the collaborating scientists.
The researchers will complement the acoustic tools with infrared cameras capable of detecting the animals' spouts when they surface to breathe. The plan, says Woods Hole researcher Daniel Zitterbart, is to install at least two thermal imaging cameras on high bluffs or peaks on the islands that line the Santa Barbara Channel. From such vantage points, the cameras will probably be able to identify a whale spout as far as five miles away, he says.
Ship strikes are believed to the leading cause of death for blue whales. In 2007, ships struck and killed at least four of the animals in and around the Santa Barbara Channel, attracting media and government attention as the whales were discovered washed ashore or dead in the water. Vessels are known to have struck 100 large whales along the California coast between 1988 and 2012, according to the National Oceanic and Atmospheric Administration.
But a decade later, ship strikes remain a serious problem, says John Calambokidis, co-founder of the Cascadia Research Collective in Olympia, Washington. He says the death toll is impossible to track because blue whales tend to sink in the ocean when killed, meaning evidence of ship-whale collisions rarely washes ashore.
"When you have a documented mortality, it may be that there were 20 that weren't documented," he says.
Commercial whaling badly depleted the global blue whale population, which scientists estimate once numbered in the hundreds of thousands. Since a worldwide moratorium on commercial whaling took effect in 1986, blue whales have begun to recover. There are an estimated 2,000 individuals in the northeastern Pacific, but that population has remained more or less stable for at least 25 years, Calambokidis notes.
"It's possible ship strikes are preventing the population from recovering further," he says.
McCauley says the shipping industry has an interest in moving swiftly between ports but that mariners also have reason to avoid whale collisions when possible.
"It's a public relations disaster when a ship comes into a harbor with a whale wrapped around its bow," McCauley says, referring to past incidents at West Coast ports.
Thomas Jelenic, vice president of the Pacific Merchant Shipping Association, which represents ships and terminal operators along the West Coast of the U.S., says the maritime industry is participating in discussions on how to reduce the collisions that injure and kill whales.
"No vessel master wants to hit a whale, and, if collisions can be avoided, we certainly want to do it," Jelenic says. "The problem is, we have very limited data on when and where whales are present. There is also a question of how effective speed reduction is at reducing lethality. If we can find the solution that is backed by scientific data, we want to participate."
The existing whale alert system for the West Coast has been marginally effective, if at all, in reducing ship strikes, according to Sean Hastings, the resource protection coordinator with the NOAA's Channel Islands National Marine Sanctuary. He said that's because nearly all ship captains that receive slowdown advisories from federal officials ignore them.
Hastings said that even financial incentives have failed to motivate cooperation from most of the shipping industry. This year the NOAA is offering ships that slow to 12 knots as they pass through the Channel Islands National Marine Sanctuary $1,000 and an extra $250 if they slow to 10 knots.
"Some ships are complying, but most are not," says Hastings, who personally conducts monthly aerial whale surveys in the Santa Barbara Channel and issues slow-down advisories by radio and email.
Along the entire West Coast this year, Hastings says, 125 ships owned by 10 shipping companies have reduced their speed in response to the NOAA's speed requests. "But that's less than 10 percent of all the shipping traffic in the spring to fall when the whales are there," he says.
Hastings notes that the advisories he and his colleagues issue for ships to reduce their speed in the presence of blue whales are not mandatory in West Coast waters.
"It's up to the shipping industry to decide if they want to do this voluntarily or not, but the regulatory approach is on the table," he says.
Calambokidis says he is fully supportive of the Benioff Ocean Initiative's plan to improve whale detection technology.
"But I'm just not convinced that improvement in the detection of whales is at the core of the problem," Calambokidis says. "It could even be counterproductive if it creates the impression that we've solved the problem. The ships have to slow down too."