Two New Right Whale Slow Zones: NE of Boston, MA and SW of Martha’s Vineyard, MA
Effective Through May 5 and 6
On April 20, 2025, the Cape Ann buoy operated by the Woods Hole Oceanographic Institution NA the presence of right whales northeast of Boston, MA. The right whale Slow Zone is in effect through May 5, 2025.
On April 21, 2025, the NOAA North Atlantic Right Whale Sighting Survey detected the presence of right whales southwest of Martha’s Vineyard, MA. The right whale Slow Zone is in effect through May 6, 2025.
As a reminder, three additional Slow Zones are also currently in effect. Locations and effective dates are listed below.
Voluntary Right Whale "Slow Zone" Areas
Mariners are requested to avoid or transit at 10 knots or less inside the following Dynamic Management Areas (DMAs) and Acoustic Slow Zones where right whales have been detected. Please visit our website for more information.
Southwest of Martha’s Vineyard, MA DMA Slow Zone: Effective April 21 - May 06, 2025
Waters bounded by:
NORTHERN BOUNDARY: 40°19′ N
SOUTHERN BOUNDARY: 39°39′ N
EASTERN BOUNDARY: 71°9′ W
WESTERN BOUNDARY: 72°1′ W
Northeast of Boston, MA Acoustic Slow Zone: Effective April 20 - May 05, 2025
Waters bounded by:
NORTHERN BOUNDARY: 42°52′ N
SOUTHERN BOUNDARY: 42°11′ N
EASTERN BOUNDARY: 70°6′ W
WESTERN BOUNDARY: 70°60′ W
Southwest of Nantucket, MA Acoustic Slow Zone: Effective April 16 - May 01, 2025
Waters bounded by:
NORTHERN BOUNDARY: 41°20′ N
SOUTHERN BOUNDARY: 40°40′ N
EASTERN BOUNDARY: 69°53′ W
WESTERN BOUNDARY: 70°46′ W
East of Boston, MA DMA Slow Zone: Effective April 14 - 29, 2025
Waters bounded by:
NORTHERN BOUNDARY: 42°35′ N
SOUTHERN BOUNDARY: 41°57′ N
EASTERN BOUNDARY: 70°23′ W
WESTERN BOUNDARY: 71°14′ W
Southeast of Nantucket, MA DMA Slow Zone: Effective April 10 - 25, 2025
Waters bounded by:
NORTHERN BOUNDARY: 40°50′ N
SOUTHERN BOUNDARY: 40°8′ N
EASTERN BOUNDARY: 68°59′ W
WESTERN BOUNDARY: 69°53′ W
Active Seasonal Management Areas (SMAs)
Mandatory speed restrictions of 10 knots or less (50 CFR 224.105) are in effect for most vessels 65 ft or longer in the following areas:
Great South Channel SMA (Apr 1 - Jul 31)
Mid-Atlantic U.S. SMAs (Nov 1 - Apr 30)
Cape Cod Bay SMA (Jan 1 - May 15)
Off Race Point SMA (Mar 1 - Apr 30)
NOTE: From March 1-April 30, Massachusetts state law requires all vessels, regardless of size, to adhere to the 10 knot speed limit within the Cape Cod Bay SMA.
Give Right Whales Room
North Atlantic right whales are on the move along the Atlantic coast of the U.S. If seen, remember that approaching a right whale closer than 500 yards is a violation of federal law.
Right Whales in Trouble
Endangered North Atlantic right whales are approaching extinction. There are approximately 360 individuals remaining, including fewer than 70 reproductively active females. Human impacts continue to threaten the survival of this species.
In August 2017, NOAA Fisheries declared the increase in right whale mortalities an “Unusual Mortality Event,” which helps the agency direct additional scientific and financial resources to investigating, understanding, and reducing the mortalities in partnership with the Marine Mammal Stranding Network, Canada’s Department of Fisheries and Oceans, and outside experts from the scientific research community.
All boaters from Maine to Virginia, or interested parties, can sign up for email or text notifications about the latest Right Whale Slow Zones. You can also follow us on Facebook (@NOAAFisheriesNEMA) and Twitter (@NOAAFish_GARFO) for announcements.
For your awareness, starting May 13, NOAA Fisheries will be sending text message alerts from a new, toll-free phone number: (844) 548-2865. This will replace our current 468-311 number. Learn more about our text message service.
Disclaimer: For quality assurance purposes please note well that while the information contained in this website is regularly vetted for accuracy it is not intended to replace the local knowledge or expertise pertaining to port conditions of our marine operations personnel.
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