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Whale Strandings

A stranded humpback whale. Photo courtesy the Atlantic Marine Conservation Society

Since 2016, various agencies along the Eastern Seaboard have been investigating unusual mortality events among whales, including humpback, minke and North Atlantic right whales.

In recent months, a growing chorus of politicians, pundits and some environmental groups have suggested that efforts to build wind farms in the water and, specifically, to use sonar to develop a contour of the ocean floor, may be confusing whales, injuring their ears or causing these marine mammals to lose their way.

Research groups such as the Atlantic Marine Conservation Society have raced to the scenes of these beachings, hoping to gather enough information to learn about the lives of these whales and conduct necropsies to determine a cause of death. [See story, “Humpback whale deaths increase along Eastern Seaboard,” TBR News Media website, Feb. 11.]

For many of these whales, however, the decaying condition of the carcass makes it difficult to draw a conclusive explanation. Additionally, some whales that weigh as much as 30,000 pounds have washed up in remote and protected places, making it difficult to analyze and remove them.

“We don’t have any evidence to suggest” a connection between wind farms and whale deaths.

— Robert DiGiovanni Jr.

Robert DiGiovanni Jr., chief scientist at AMCS has responded to over 4,600 strandings of marine mammals and sea turtles and has tagged over 120 animals, according to the society’s website. Currently, he is serving as the principal investigator on aerial surveys in the mid-Atlantic region.

Pointing to data from the National Oceanographic and Atmospheric Administration, DiGiovanni suggested that many of the whale strandings relate to vessel strikes.

According to NOAA data, 181 humpback whale mortalities occurred between 2016 and early February of this year. Researchers were able to conduct necropsies on about half of those whales. Of those examined, about 40 percent had evidence of a ship strike or entanglement.

“We don’t have any evidence to suggest” a connection between wind farms and whale deaths, DiGiovanni said. “What we’re seeing is what we’ve been previously seeing.”

He urged a close examination of all the changes and factors that could affect the location and health of whales, “not just one source.”

The chief scientist advocates consistent and ongoing investment in research on a larger scale, which could aid in responding to ongoing concerns about whale mortality events.

Understanding where whales are located is critical to protecting them.

DiGiovanni pointed to street signs around schools and neighborhoods that urge drivers to slow down because there might be children running into the street or playing on lawns.

Similarly, research about the location and movement of marine mammals can enable policies that protect them while they’re around the shores of Long Island and, more broadly, the Eastern Seaboard.

Researchers need to get a “better understanding of where these animals are and how that changes from day to day, week to week and month to month,” DiGiovanni said.

In aerial surveys a few years ago in the first week of February, he saw one or two whales. Two weeks later, he saw 13 right whales.

“We need to get a better understanding of those changes to help manage that,” the chief scientist said.

Against the backdrop of ongoing unusual mortality events, DiGiovanni noted that whale deaths occurred consistently before and during the COVID-19 pandemic.

“We saw a difference in what was going on in the world, but we still had large whale occurrences,” he said. “Pulling all these pieces together is really important.”

The Atlantic Marine Conservation Society is working to develop incident command systems for marine mammal strandings with towns, fire departments, police and other authorities.

When DiGiovanni gets a call about a stranded whale, he can reach out to local partners, particularly in areas where these events have occurred in the past. Such rapid responses can ensure the safety of the crew and any bystanders on-site and can help bring needed equipment.

“What we do is very specialized,” DiGiovanni said. “Getting people to understand that and getting what’s needed is usually the first challenge.” 

Members of the conservation society team sometimes work 12 or 14 days straight without a break, depending on the complexity of a stranding and the number of whales washing up on beaches.

“The people doing this work are extremely dedicated to what they’re trying to answer” about the life and death of marine mammals, he added. Some of them drive six hours to a site to bring their expertise to bear.

“The discovery part is why we do this — to answer questions that would otherwise go unnoticed,” DiGiovanni said.

Floating humpback whale offshore of Delaware. Photo courtesy the Marine Education, Research & Rehabilitation Institute

This year has been tough for the population of humpback whales, as eight of them from Maine to Florida have had so-called unusual mortality events as at Feb. 7.

Indeed, a 41-foot humpback whale was discovered washed up Jan. 30 at Lido Beach on the South Shore. The whale likely died after a vessel strike, National Oceanic and Atmospheric Administration Officials said.

Threats to whales in the area include getting hit by boats, becoming entangled in fishing lines and ocean noise.

The last of these potential dangers to humpbacks has received considerable attention from some members of the popular press, who have suggested that the process of installing wind farms along the coastline has or may create the kind of noises that can cause trauma to whale ears and that might throw a whale off course in its search for food.

To provide a broader context, unusual mortality events have been occurring for humpback whales since 2016, as 180 have been stranded along East Coast states since that time, according to NOAA data.

Scientists were able to study about half of the total humpback whale strandings from 2016 and attributed about 40% to ship strike or entanglements. The rest either died from starvation, parasites, inconclusive causes, or were in places where it would have been difficult to study and analyze them. 

The combination of whales distracted by feeding and boat traffic has led to some of the deaths.

“Our waterways are one of the busiest on Earth,” said Nomi Dayan, executive director of The Whaling Museum & Education Center of Cold Spring Harbor. “During busy eating months, when they are gorging, it’s harder to pay attention” to what’s around them.

Many of these humpback whale deaths occurred during periods when wind farm activity was low along the Eastern Seaboard.

“What we’re seeing right now [in terms of whale strandings] is something that has been going on for years,” said Lesley Thorne, associate professor in the School of Marine and Atmospheric Sciences at Stony Brook University. 

In a press conference last month, officials suggested that the wind farms, which are designed to reduce the reliance on fossil fuels, cut down on carbon emissions and slow global warming, are not likely to make what is already a challenging period for humpbacks even worse.

“At this point, based on the information that we do have, we do not believe the evidence supports that those planned construction activities would exacerbate or compound these ongoing unusual mortality events,” Ben Laws, biologist with NOAA Fisheries Office of Protected Resources, said during a Jan. 18 conference call with reporters.

‘What we’re seeing right now [in terms of whale strandings] is something that has been going on for years.’

— Lesley Thorne

As part of the investigation process, NOAA has brought together an independent team of scientists to coordinate with the Working Group on Marine Mammal Unusual Mortality Events to review data, sample stranded whales and determine the next steps for this investigation.

The scientists include marine mammal stranding network members, academics and veterinarians with local state and federal biologists.

At this point, most of the surveys off the coasts of New York and New Jersey are “characterizing the seafloor and the sub-bottom for engineering purposes for the foundation of offshore wind facilities as well as looking at cable burial risks along that route,” Brian Hooker, marine biologist in the Bureau of Ocean Energy Management, said on the press call.

Slower boat speeds

Reducing boat speeds in areas where whales are likely hunting for food or migrating can reduce the likelihood of vessel strikes and, in the event of contact, can improve the outcome for whales.

“What’s been demonstrated in the past is that, with faster vessels, collisions are more likely to occur and it’s more likely for that collision to be fatal,” Thorne said. The specific speeds or thresholds that are more likely to cause fatal collisions vary depending on the whale species.

The whales around Long Island include sei whales, North Atlantic right whales, finback whales, minke whales and, rarely, blue whales, according to Dayan.

Some management strategies for a host of whales such as the North Atlantic right whale include seasonal management areas, in which boats around a particular area during a specific season are required to travel more slowly.