What’s causing right whale decline?


To the Editor:

There is no argument that the North Atlantic Right Whale is in dire straits. Dr. Mark Baumgartner, a biologist from the Woods Hole Oceanographic Institute, gave a compelling presentation on “The Plight of the Right Whale” this past Tuesday evening, Jan. 23, at the Vineyard Gazette office. Since it was advertised, it was well attended.

One point of interest was that the right whales were making a healthy comeback, a two-decade period of modest annual growth; the population rebounded from 270 living whales in 1992 to 483 in 2010. From 2010, the numbers began to decline rapidly, with 2017 being a particularly devastating year, a loss of 17 whales. Dr. Baumgartner stressed the main focus was on whale entanglements with snow crab and lobster gear, and the urgent measures needed to be taken immediately within the fishery. Massachusetts fishermen are leading the way with break away links at the base of surface buoys (to 600lbs in 2001), sink rope (mandated in 2003), gear reductions and seasonal gear restrictions in Cape Cod Bay. He also touched on ship strikes as being a cause of death. However, the Marine Mammal Commission stated on their website, “other potential threats include spills of hazardous substances from ships or other sources, and noise from ships and industrial activities.”

But what Dr. Baumgartner could not explain was the scarcity of food that these leviathans need to feed on and their low birth rate. He showed the audience slides on the Calanus finmarchicus, known as copepods and remarked that this type plankton, sought after by these whales, are basically comprised of fat, or as Dr. Baumgartner called them “buttersticks.” Each adult whale needs to consume between 1,000-2,000 a day to remain healthy. The birth rate has dropped 40 percent from 2010-2016 and all five calves that were born in 2017 were to older mothers. “Since about 2011, we’re not seeing those sub-adults and juveniles in Florida and the question is, well, where are they?” asks Jim Hain, senior scientist at Associated Scientist at Woods Hole. Scott Kraus, a marine mammalogist from the New England Aquarium in Boston says, “Females are having young just every 9 years or more, compared with every 3 years in the 1980’s.”

Perhaps the decline is linked to the environmental disaster on April 20, 2010, the Deep Water Horizon oil spill in the Gulf of Mexico. From April 20, 2010, to July 15, 2010, more than 200 million gallons of oil spilled into the Gulf followed by another one million gallons of Corexit, a dispersant mixture of solvents and surfactants that break down the oil into tiny droplets. It is documented that for 3 months, marine microorganisms have ingested these toxins, which are carried along the Gulf Stream, a strong underwater current that flows through the Gulf of Mexico, skirts around Florida, flowing between Cuba and up the Eastern seaboard. Since the right whale gives birth off the coasts of Georgia and Florida, could these toxic chemicals be part of their decline?  “The chemicals in the oil product that move up through the food web are a great concern for us,” said Teri Rowles, coordinator of NOAA’s marine-mammal health and stranding response program. It is also documented that female mammals including humans who have been in contact with these toxins have suffered from irregular menstrual cycles, infertility, miscarriages and stillborns, along with premature aging and other debilitating side effects. John Pierce Wise Sr., co-author of the 2014 study and head of the Wise laboratory of Environment and Genetic Toxicology at the University of Southern Maine says, “To put it simply, after a sudden insult like an oil spill, once it’s over, it takes a long time for the population effects to fully show themselves.” This same article states “research has shown that the calves of other baleen whales (other than Bryde’s whale) may be particularly vulnerable to toxins that build in their tissues.”

A letter dated Aug. 17, 2017, from the office of the Massachusetts Attorney General in “Reference for information and comments of the 2019-2024 National Outer Continental Shelf Oil and Gas Leasing Program,” refers to the Deepwater Horizon disaster and its “harm to coastal communities and marine environment” and “long ranging impacts on marine mammals. The impacts on sea turtles could span the Atlantic.” The letter also states, “from 2010 through September 2016, there were 43 significant oil spills.”

In an article dated Dec. 5, 2017, ecologist Peter Corkeron of NOAA’s Northeast Fisheries Center in Woods Hole at the North Atlantic Right Whale Consortium’s annual meeting, “They’re (female right whales) dying too young, and they’re not having calves often enough.” This study found the females are struggling to reproduce. Dr. Baumgartner is the president of the North Atlantic Right Whale Consortium.

To sum it up, “the impacts from the 2010 Deepwater Horizon oil spill not only continue in the Gulf but have resulted in a domino effect of upsets to whales and dolphins throughout the U.S.” and in an article from NOAA titled “Impacts of Oil on Marine Mammals and Sea Turtles” “long term chronic effects such as decreased survival and lowered reproductive success may occur.

Even if this hypothesis is debunked, it is fact that the right whale food source is dwindling. According to a Canadian Broadcasting Corporation article dating Sept. 21, 2017, “the overall abundance of copepods are decreasing.” “We’ve found that when there’s a period of years and prey is low and less available for the right whale, they reproduce slower,” said Erin Meyer-Gubrod, a post-doctoral scholar in marine phenology at the University of California, Santa Barbara. An audience member during Dr. Baumgartner presentation asked him if there was anyway to replicate the copepod in the laboratory. His reply was not in the amounts the whales need on a daily basis.

These findings make an excellent case for alternative “green energy” but the offshore wind farm developers are not off the hook. According to Dr. Baumgartner, the right whale is a very social animal and relies heavily on its sense of sound to communicate with other whales for courtship and food. It is well documented in studies from Europe that “the major environmental concerns related to offshore wind developments are increased noise levels, risk of collisions, changes to benthic and pelagic habitats, alterations to food webs and pollution from increased vessel traffic or release of contaminants from seabed sediments.” In an article dated July 28, 2017, Dr. Ingrid Biedrton from Oceana states, “North Atlantic right whales can’t take any more noise in their environment.” On the Marine Mammal Commission’s website, “pile driving” is considered a threat to the right whale. Since the right whale is already threatened, will the construction of offshore wind farms cause further stress on an already declining right whale population? Dr. Baumgartner said he didn’t know.

According to Dr. Mark Baumgartner, beginning in 2010, gear entanglements and ship strikes seem to be the leading culprit to the right whale’s decline. But are there other factors to look at as well?

Susan M. Larsen