The East Coast Whale Die-Offs: Unraveling the Causes

This winter’s humpback strandings in Latest York and Latest Jersey look strikingly similar to people who occurred from December 2016 through February 2017 in Virginia and North Carolina, by way of variety of animals, geographic radius, and average variety of days between strandings. And yet activist groups, politicians, and the media are falsely framing the Latest York and Latest Jersey strandings as unprecedented. The claim was first made in January, after the states experienced five humpback strandings, and the allegation has since engulfed coastal towns in Latest Jersey, where construction of the biggest offshore wind farm within the U.S. is about to start as early as next 12 months.

Constructing wind farms off the Eastern Seaboard has been discussed for many years. Nevertheless, the Biden Administration, with the support of 11 coastal states, has hurried to carve out huge swaths of ocean for development. Latest Jersey has been probably the most ambitious, setting a goal to power greater than 3.2 million homes with offshore wind energy by 2035. Last 12 months, the energy firms Ørsted and Atlantic Shores began conducting seafloor surveys off the coast of southern Latest Jersey for his or her respective lease areas, which have space for lots of of turbines.

That work drew little attention. But after the January strandings, groups against offshore wind development began blaming the deaths on the surveying, a few of which uses pulses of sound to map the seafloor surface and subsurface. Since then, 30 mayors of coastal Latest Jersey municipalities, together with several of the region’s state and federal representatives, have called on each Latest Jersey’s governor and President Biden to pause all activity by offshore wind firms until an investigation determines the reason behind the strandings.

“The work related to offshore wind projects is the first difference in our waters,” Latest Jersey state senator Vince Polistina said in January, referring to recent changes within the ocean that is perhaps drastic enough to trigger whale strandings. “And it’s hard to imagine that the death of [these] whales on our beaches is only a coincidence.”

Nevertheless, the Marine Mammal Commission, an independent government agency that oversees the conservation of marine mammals and their environment, said in February that “there isn’t any evidence to link these strandings to offshore wind energy development.” It added, “Although these strandings have generated media interest and public scrutiny, this isn’t an unusually large variety of whales to strand during winter.” Indeed, since NOAA declared the beginning of the UME in 2016, each Latest Jersey and Latest York have seen high numbers of strandings — Latest York alone has had 36 up to now seven years — though they’ve occurred more often within the spring and summer.

While certain kinds of sound have been shown to harm cetaceans, the scientists who study the impact of sound on marine mammals say the categories recently utilized by Ørsted and Atlantic Shores operate at frequencies that pose little risk to baleen whales just like the humpback. And, scientists who study whale behavior usually say it’s inconceivable to definitively link the strandings to a single cause given the complexity of the ocean, the dramatic changes the North Atlantic has experienced in recent many years, and the way much remains to be unknown about how these changes is perhaps affecting baleen whales.

“If we’re being honest here, this isn’t nearly humpback whales,” says Alex Costidis, who leads the Virginia Aquarium & Marine Science Center’s Stranding Response Program and can be a member of the National Marine Fisheries Service’s working group for Marine Mammal Unusual Mortality Events. “That is about a fairly stressed marine environment that we’re continuing to emphasize at increasing rates while really having a really poor understanding of what the last word impacts are.”

Because there are not any large-scale wind farms off the U.S. East Coast, the one option to achieve the most effective possible understanding of their impacts on marine life, Costidis and other scientists say, is to have a greater understanding of the marine environment now — not after turbines have been constructed. Indeed, last 12 months the state of Latest Jersey mandated Ørsted and Atlantic Shores to dedicate $26 million to baseline research, like using seafloor-anchored listening devices to watch marine mammal presence and analyzing environmental DNA to trace the movements of fish species. A few of that work has began. Some will begin this 12 months. Already, though, there are clear signs of the stressors to the marine environment that worry Costidis.

The North Atlantic has warmed dramatically in recent many years. In 2022, its “ocean heat content” — a measure of the quantity of warmth stored by the ocean — reached its highest point since recordkeeping began within the Fifties. The Gulf of Maine, a key feeding ground for humpback and other baleen whales, is warming even faster. This will be influencing seasonal changes within the whales’ distributions that scientists have noticed in the previous few many years — changes that mirror those which can be occurring amongst their prey, which include krill and Atlantic menhanden.

Historically, humpbacks largely remained in northern waters between the Gulf of Maine and Norway from spring through summer, then migrated south to the tropics to calve and mate within the winter. But recently, their distribution has been wider. “What we’ve seen up to now twenty years is humpback whales in several areas to the south, most of them seeming to be juveniles, feeding off the Mid-Atlantic states in winter when many of the population can be migrating to the Caribbean,” says Jooke Robbins, a senior scientist with the Center for Coastal Studies’ Humpback Whale Studies Program. “Prior to now decade, we’ve began to see whales popping up in summer within the waters off Latest York, Latest Jersey, and Rhode Island, which appears to be an extension of the conventional feeding season.”

Kevin Wark, a business fisherman who has spent his life and profession working the waters off Latest Jersey, also says that predator-prey dynamics within the Latest York Bight — because the waters off Latest York and Latest Jersey are known — have shifted significantly lately. “The menhaden population is robust and the whales have learned that they’re a simple goal,” says Wark, who has worked as Atlantic Shores’ “fisheries liaison officer” since 2019. Recalling the past 12 months, he continues, “I’ve never seen so many humpbacks within the ocean — just crazy amounts of whales.”

Over the past decade, the quantity of products handled by ports up and down the coast — but especially in Latest Jersey, Latest York, Pennsylvania, and Delaware — has grown rapidly. Through the coronavirus pandemic, shipping traffic exploded. The variety of containers handled on the Port of Latest York and Latest Jersey increased by 27 percent between 2019 and 2022. Simply to the south, the Port of Philadelphia is now the fastest growing port within the nation.

This confluence of more whales and more ships in a latest area presents an unlucky but logical clue to the UME. Researchers conducted partial or full necropsies on about half of the stranded whales because the UME began in 2016, and about 40 percent of those examined had signs of injury by the hands of humans. “We proceed to see evidence suggesting similar causes at play, namely vessel collisions and fishing gear entanglement,” Costidis says. “We are able to speculate all we would like, but that’s what the evidence is currently showing us.”

Indeed, almost the entire humpback strandings which have occurred in Latest York and Latest Jersey this winter had clear signs of vessel strike, though it’s unknown if the collisions occurred before or after the whales died. (A lot of the full necropsy results are still pending.)

Even before the pandemic, vessel strikes and equipment entanglement were among the many predominant causes of anthropogenic mortality amongst large whales globally, and amongst North Atlantic humpbacks specifically. The species has been called “cosmopolitan” for its ability to seemingly tolerate the urbanized waters of the Latest York Bight. A study published in 2021 found that humpbacks foraging within the nearshore waters of this region between 2018 and 2020 “were exclusively juveniles that were surface feeding,” and that 93 percent of humpbacks struck were juveniles.

“I don’t need to say there are only juveniles within the Latest York Bight,” says Lesley Thorne, a co-author of the 2021 study and an associate professor in Stony Brook University’s School of Marine and Atmospheric Sciences. “But actually” — in comparison with adults — “they’re the animals occurring near shore and [are] potentially more vulnerable due to that difference in habitat use.” Thorne says scientists are usually not yet sure why juveniles are more prevalent closer to shore, though Robbins identified that young humpbacks appear to chase Atlantic menhaden greater than adults do.

In 2008, NOAA established speed restrictions to assist reduce the chance of vessel strikes for giant whales, particularly North Atlantic right whales. However the rule is difficult to implement, especially as shipping channels develop into more crowded with more ships and whales. “We’ve been documenting vessel strikes and entanglements in large whales for many years, but it surely’s also becoming more prevalent as vessels get faster and fishing rope gets stronger,” says Michael Moore, a senior scientist on the Woods Hole Oceanographic Institute who has spent his 40-plus-year profession studying marine mammals, with a give attention to North Atlantic right whales. “So the tools for trauma are there, they usually’re well defined by way of what’s causing mortality. At what point does an unusual event develop into usual?”

Not only are vessels crowding the water’s surface, where humpbacks feed. Also they are making it loud down below. The Latest York Bight’s submarine environment is always subjected to sounds from shipping and other sources, including the pinging of sonar from government activities, which can include nautical charting and geologic mapping; from academic institutions conducting historical geological studies; and from beach replenishment operations looking for suitable sand deposits.

“We’re fighting this battle against Cousteau’s silent world,” says Doug Nowacek, who heads the Nowacek Acoustics and Engineering Lab at Duke University, which is currently researching how sound from the event of offshore wind sites might impact marine mammals. “It’s not cool down there.”

Understanding this level of din is vital when attempting to asses the impact of other sources of sound — just like the seafloor surveys conducted by Ørsted and Atlantic Shores — on whales comparable to humpbacks. The businesses have used several kinds of survey equipment that use high frequency sound waves to map the seafloor inside their lease areas. High frequency sounds are harder for baleen whales to listen to, Nowacek says, and haven’t been shown to affect them beyond behavioral disturbances. Moreover, says Nowacek, these high frequency pulses quickly lose intensity as they spread from their goal area on the seafloor.

The kinds of sounds that baleen whales are most sensitive to are low frequency and meant to travel long distances. Probably the most well-known uses of low frequency sound are military sonar and seismic surveying conducted by the oil and gas industry, which uses huge arrays equipped with dozens of air guns to pulse sound waves kilometers below the seafloor. Each Ørsted and Atlantic Shores did conduct surveys that utilize lower frequencies, but because they only have to penetrate about 100 feet into the seafloor, the equipment is way smaller and emits far less sound-intensive pulses. (While military sonar has been directly linked to baleen whale strandings, seismic surveying has not.)

In response to an Ørsted spokesperson, the corporate has not conducted those tests “offshore of South Jersey because the summer of 2022.” It’s unclear when Atlantic Shores last used lower frequency surveying. Nevertheless, for a humpback to be disoriented enough by Ørsted’s surveying — even its lowest frequency activity — “it could should be mainly right next to it,” says Nowacek. Such an in depth encounter is unlikely, on condition that all offshore wind survey ships are required to have trained observers onboard whose job is to be certain that marine mammals are avoided and that sonar work is stopped once they are nearby.

Nevertheless, “for a whale to really be injured because of this of 1 ping from those things, it could should be mainly right next to it,” says Nowacek. Such an in depth encounter is unlikely, on condition that all offshore wind survey ships are required to have trained observers onboard whose job is to be certain that marine mammals are avoided and that sonar work is stopped once they are nearby.

Nowacek stressed that the impact of noise on marine mammals “isn’t something to be trifled with.” He and other scientists also emphasize that they’re concerned by how little remains to be known about how the North Atlantic is changing, how marine mammal behavior might shift because of this of those changes, and the way lots of of wind turbines within the marine environment might further exacerbate all this variation.

“We’re trying to grasp why these whales are here, to take a look at the resources they’re depending on,” says Robbins, of the Center for Coastal Studies. “There’s whole teams of individuals working under really terrible conditions, conducting necropsies, trying to take a look at each death fastidiously.” The questions are difficult, she adds, they usually proceed to mount. “But to attract a conclusion before a really complicated query has been sorted out is definitely just drawing resources and a focus away from the thing it would really be.”