Right whales are gathering south of Martha’s Vineyard in numbers researchers have only begun to understand, facilitated by studies of the area in advance of the development of offshore wind farms.
“We didn’t know about it,” said Scott Kraus, marine mammals chief scientist at the New England Aquarium.
The Boston aquarium has just begun a one-year specialized aerial survey of the endangered right whales, other large whales, dolphins and sea turtles in federal areas south of the Vineyard that have been leased for wind energy projects. A simultaneous boat-based study in the area by the Woods Hole Oceanographic Institution and the Center for Coastal Studies in Provincetown will examine food density and composition that is drawing right whales to that area.
“The food is the lure,” said Charles “Stormy” Mayo, right whale habitat expert at the Provincetown center.
A 2011-2015 marine wildlife study, funded first by the Massachusetts Clean Energy Center and in conjunction with the federal Bureau of Ocean Energy Management, alerted researchers to the undocumented right whale feeding area.
There are 524 North Atlantic right whales in the world, and many of the ones seen south of the Islands are the same ones seen in Cape Cod Bay and throughout New England waters. A female named Pico, for example, was seen in Cape Cod Bay on Jan. 30 by airplane surveyors from the Provincetown center and then on March 6 by the aquarium’s surveyors off the Vineyard. A male first documented in 1985, who is called “Wavy Gravy” for the shape of his flukes, has been seen south of the Vineyard, as has another male first documented nearly 40 years ago.
Getting from Cape Cod Bay to south of the Vineyard is nothing for a right whale.
“They can swim 100 miles in a day,” Kraus said.
While the newly discovered right whale gatherings have attracted scientists studying population trends, food sources and more, the information arose because state offshore wind energy officials want to answer some basic questions.
The four-year study sets baseline data about marine wildlife in the lease areas, and that information could be used in federal and state environmental permitting in the future, Massachusetts Clean Energy Center Offshore Wind Director William White said.
“We’re front-loading it in order to expedite the process,” White said.
In addition, it became apparent that a one-year specialized survey of marine mammals, both from the air and the water, was needed, he said. The Clean Energy Center and the Bureau of Ocean Energy Management will again split the annual $1 million expense of the work, White said.
The 2011-2015 study found right whales in the lease areas from December through April, with a peak in March. The whales were in the area for short-term feeding, the study revealed.
In the past, a year-round airplane survey of the Gulf of Maine, conducted by the Northeast Fisheries Science Center, and the seasonal survey of Cape Cod Bay by the Provincetown center have helped researchers keep track of right whales in New England waters. Now, surveyors are reporting from south of the Islands as well.
From mid-February through mid-March, a voluntary boat speed restriction was announced south of the Vineyard because of reports of 10 to 14 right whales. At around the same time, close to 30 right whales were reported in airplane surveys in Cape Cod Bay.
The whales start to congregate once a certain density of zooplankton is reached.
“It’s like picking blueberries in the wild,” Mayo said. “You wander around until you find a clump.”
WHOI biologist Mark Baumgartner will draw food density data from the lease areas, and Mayo will compare that with what the center knows from its studies in Cape Cod Bay, including the food “profile” needed for a right whale to open its mouth to eat. The presence of that profile leads to congregating right whales.
The yearlong specialized survey does not include acoustic studies for marine mammals nor avian studies because researchers believe that the data in the 2011-2015 study was sufficient for those purposes.
Three offshore wind energy companies have signed commercial leases with the federal government for areas south of the Vineyard. At the same time, the state’s three electric distribution companies are expected to issue a request for proposals by June 30 for the companies to sell their wind energy to the utilities under state guidelines. No wind farms have been built in the area yet. All three companies are in the site assessment phase of the regulatory process.