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Voluntary Vessel Speed Restriction Zone Established South of Nantucket to Protect Right Whales

November 19, 2018

New voluntary vessel slow speed zone established to protect a group of four right whales spotted south of Nantucket.


A voluntary vessel speed restriction zone (Dynamic Management Area or DMA) has been established 21 nautical miles south of Nantucket, MA to protect an aggregation of four right whales sighted in this area on November 18, 2018.

This DMA is in effect immediately through December 3, 2018. 


Mariners are requested to route around this area or transit through it at 10 knots or less.

South of Nantucket, MA DMA coordinates:

41 16 N
40 37 N
070 42 W
069 47 W 

There is also a Seasonal Management Area in effect in Block Island Sound through April 30, 2019. A mandatory speed restriction of 10 knots or less (50 CFR 224.105) is in effect in Block Island Sound.

Right Whales Are Migrating South

North Atlantic right whales are on the move along the Atlantic coast of the U.S. With an unprecedented 20 right whale deaths documented in 2017 and 2018, NOAA is cautioning boaters to give these endangered whales plenty of room as they migrate south. We are also asking commercial fishermen to be vigilant when maneuvering to avoid accidental collisions with whales, remove unused gear from the ocean to help avoid entanglements, and use vertical lines with required markings, weak links and breaking strengths.

Right Whales in Trouble

North Atlantic right whales are protected under the U.S. Endangered Species Act and the Marine Mammal Protection Act. Scientists estimate there are slightly more than 400 remaining, making them one of the rarest marine mammals in the world.

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.

More Info

Download the Whale Alert app for iPad and iPhone

Send a blank message to receive a return email listing all current U.S. DMAs and SMAs.

Details and graphics of all ship strike management zones currently in effect.

Reminder: Approaching a right whale closer than 500 yards is a violation of federal and state law. 

Last updated by Greater Atlantic Regional Fisheries Office on November 19, 2018