2016-2018 Humpback Whale Unusual Mortality Event along the Atlantic Coast

Floating whale offshore of Delaware.

Floating whale offshore of Delaware. 

Photo credit: Marine Education, Rehabilitation and Research Institute


Since January 2016, elevated humpback whale mortalities have occurred along the Atlantic coast from Maine through Florida. A table of stranding numbers by state is below.

This event has been declared an Unusual Mortality Event.

Humpback Whale Strandings by State
State 2016 2017 2018 (as of 6/1) Total
Delaware 3 2 0 5
Florida 0 0 2 2
Georgia 0 0 1 1
Massachusetts 3 6 2 11
Maryland 1 1 0 2
Maine 2 0 1 3
North Carolina 4 6 1 11
New Hampshire 1 0 0 1
New Jersey 2 3 2 7
New York 4 5 5 14
Rhode Island 2 3 0 5
South Carolina 1 0 0 1
Virginia 3 7 3 13
TOTAL 26 33 9 76

Partial or full necropsy examinations were conducted on approximately half of the whales. Of the whales examined, about 50% had evidence of human interaction, either ship strike or entanglement.

Causes of the humpback whale UME

A portion of the whales have shown evidence of pre-mortem vessel strike; however, this finding is not consistent across all whales examined. More research is needed.

As part of the UME investigation process, NOAA assembled an independent team of scientists to coordinate with the Working Group on Marine Mammal Unusual Mortality Events to review data, sample stranded whales, and determine the next steps for the investigation.




Report a stranded or floating whale

The most important step members of the public can take to assist investigators is to immediately report any sightings of live whales in distress or stranded, or dead whales. Make the report by calling the Greater Atlantic Marine Mammal Stranding Hotline at 866-755-6622, the Southeast Marine Mammal Stranding Hotline at 877-433-8299 or contact the U.S. Coast Guard on VHF Channel 16.  Do not approach or touch injured or dead marine mammals.

Dead stranded humpback whale showing evidence of pre-mortem propeller injuries.

Dead stranded humpback whale showing evidence of pre-mortem propeller injuries.  
Photo Credit: Virginia Aquarium

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