
2016–2023 Humpback Whale Unusual Mortality Event Along the Atlantic Coast
Since January 2016, elevated humpback whale mortalities have occurred along the Atlantic coast from Maine through Florida.

Learn more about Marine Mammal Unusual Mortality Events
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 was declared an Unusual Mortality Event in April 2017, and includes stranded humpback whales from 2016.
State | 2016 | 2017 | 2018 | 2019 | 2020 | 2021 | 2022 | 2023 | Total |
---|---|---|---|---|---|---|---|---|---|
Maine | 2 | 0 | 2 | 0 | 1 | 0 | 2 | 0 | 7 |
New Hampshire | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 |
Massachusetts | 3 | 7 | 4 | 4 | 10 | 4 | 3 | 2 | 37 |
Rhode Island | 2 | 3 | 0 | 1 | 0 | 0 | 3 | 1 | 10 |
New York | 4 | 5 | 8 | 5 | 9 | 1 | 2 | 5 | 39 |
New Jersey | 3 | 3 | 2 | 5 | 4 | 0 | 4 | 7 | 28 |
Maryland | 1 | 1 | 0 | 0 | 0 | 1 | 0 | 1 | 4 |
Delaware | 3 | 2 | 1 | 1 | 1 | 0 | 0 | 0 | 8 |
Virginia | 2 | 7 | 4 | 6 | 4 | 1 | 1 | 6 | 31 |
North Carolina | 4 | 6 | 2 | 4 | 3 | 3 | 4 | 1 | 27 |
South Carolina | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 |
Georgia | 0 | 0 | 1 | 1 | 0 | 0 | 0 | 0 | 2 |
Florida | 0 | 0 | 2 | 0 | 1 | 0 | 0 | 0 | 3 |
TOTAL | 26 | 34 | 26 | 27 | 33 | 10 | 19 | 23 | 198 |
Partial or full necropsy examinations were conducted on approximately half of the whales. Of the whales examined (approximately 90), about 40 percent 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 Stranding
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. Photo: Virginia Aquarium.
Interactive Map
More Information
- Frequent Questions: 2016–2023 Humpback Whale Unusual Mortality Event
- Frequent Questions: Offshore Wind and Whales
- Media Teleconference on East Coast Whale Strandings (January 18, 2023)
- Donate to the Unusual Mortality Event Contingency Fund
- Unusual Mortality Events
- Marine Mammal Health and Stranding Response Program
- Marine Mammal Protection
