Here's what federal scientists say is likely killing whales off the NJ coast

Amanda Oglesby, Asbury Park Press
Thu, January 19, 2023 

Seven whale deaths along the coasts of New Jersey and New York in as many weeks have marine scientists seeking answers and federal authorities making assurances that offshore wind development is not to blame.

On Wednesday, the National Oceanic and Atmospheric Administration, or NOAA, held a phone conference with journalists across the country to address what the agency called an ongoing "unusual mortality event" among humpback whales.

Since early December, four dead humpback whales and one sperm whale have washed ashore New Jersey beaches. Another two whales washed up dead on Long Island beaches.

Researchers perform a necropsy on a female humpback whale that washed ashore in Brigantine on Jan. 12, 2023. The whale is the latest to wash onto New Jersey beaches in recent weeks.

Since 2016, 178 humpback whales deaths were documented along the Atlantic Coast, according to NOAA. Of those, 22 washed onto New Jersey beaches, according to the agency.


On Tuesday, a 20-foot humpback whale washed ashore on Assateague Island in Virginia, the latest in a concerning recent spike along the mid-Atlantic coast.

At issue is claim by some environmental and citizens groups that noise created from underwater mapping and soil testing spooks whales and causes them to strand or die. Last week, the environmental organization Clean Ocean Action called for a halt to offshore wind farm surveys until the whales' deaths could be fully investigated.

The high death rates predate any offshore wind activity in the Atlantic, according to NOAA.

Related:Why are so many dead whales washing up on NJ shores?

There is no evidence that sound generated during high-resolution geophysical surveys, which are used to map sea floors for offshore wind farms, harms marine mammals, said Erica Staaterman, a bioacoustician at the federal Buruea of Ocean Energy Management's Center for Marine Acoustics. The surveys map the ocean floor by bouncing sound waves.

Whales also use sound and calls to communicate, locate food and identify potential predators, according to NOAA's National Ocean Service. Vessel- and human-generated noise in water decreases the distance over which humpbacks can communicate and detect predators and prey, according to a 2018 study published in the journal Frontiers in Marine Science.

But not all sound generated by human activity and high-resolution geophysical surveys can be heard by large whales like humpbacks, who hear in lower frequencies than other species, Staaterman said.

In addition, no whale strandings have ever been documented from offshore wind development noise, said Benjamin Laws, deputy chief for the permits and conservation division at NOAA's Fisheries Office of Protected Resources.

Volunteers and marine mammal experts gather on Sunday, Jan. 8, 2023 to analyze and prepare to bury a dead whale that washed ashore in Atlantic City.

About half of the dead humpback whales documented by NOAA were necropsied, with the remainder being too decomposed for research teams to determine their cause of deaths, said Sarah Wilkin, coordinator of the Marine Mammal Health and Stranding Response Program at NOAA's Fisheries Office of Protected Resources. Of the half that were thoroughly examined, about 40% of the animals showed signs of entanglements with fishing gear or ship strikes, she said.

Minke and North Atlantic right whales are also dying in unusually high numbers, according to NOAA researchers.

"Unfortunately, it's been a period of several years where we have had elevated stranding of large whales," said Wilkin. "But we are still concerned about the pulse (of whale deaths) over the past six weeks or so."

Humpback whale populations have risen in the New York Harbor and New Jersey coastal areas over the past decade, said Paul Sieswerda, executive director of Gotham Whale, an advocacy and research organization focused on marine mammals in and around New York. The humpbacks are being attracted to the coast by large schools of menhaden, he said.

"It's kind of a a good news story of the Hudson River cleaning up and influencing the area around New York and New Jersey in a positive manner," said Sieswerda. "I'm afraid to say that the increase in numbers of whales has increased the risk to those whales, in an area that is the most active port on the Eastern Seaboard… They're playing in traffic."

Wilkin said scientists at NOAA are still evaluating the causes of deaths of the humpbacks and whether vessel strikes are becoming more common among whales.

"Samples were collected for most of these cases that will be sent off to different laboratories and other scientists for analysis," she said. "That may give us some answers in the weeks and months to come, but it may also unfortunately… remain inconclusive."

Amanda Oglesby is an Ocean County native who covers Brick, Barnegat and Lacey townships as well as the environment. She has worked for the Press for more than a decade. Reach her at @OglesbyAPP, aoglesby@gannettnj.com or 732-557-5701.

This article originally appeared on Asbury Park Press: NJ whale deaths likely caused by vessel strikes, fishing gear: Feds