Dolphins and porpoises are at the top of the food chain and play an important role in the overall balance of the marine environment. They belong to a group of marine mammals called cetaceans. Marine mammals in the cetacean family include whales, dolphins, and porpoises. These animals are often referred to as “sentinels” of ocean health providing insight into marine ecosystem dynamics. Numerous studies have explored the effects of noise and chemical pollution, habitat degradation, and changes in climate on these animals.
Dolphins and porpoises tend to be social and live in groups. They exhibit complex methods of communication and echolocation making squeaks, buzzes, whistles, and clicks that can be heard from miles away. They are also thought to communicate by slapping the water’s surface with their tails or bodies. They range in size from the small, critically endangered vaquita porpoise to the iconic killer whale—the largest member of the Delphinidae, or dolphin family.
All dolphins and porpoises are protected under the Marine Mammal Protection Act, and some are also listed under the Endangered Species Act. Together with our partners, we work to study, protect, and conserve these fascinating species and their habitats.
Species News
Gervais’ beaked whale on the beach at Emerald Isle in North Carolina. Credit: NOAA Fisheries
A new study has classified the North Atlantic right whale stock as very highly vulnerable to climate change. Credit: NOAA
Necropsy of a dead humpback whale that was reported at the mouth of the Chesapeake Bay. The whale drifted near the Bay Bridge Tunnel, and the local stranding network pulled it up on land by using heavy equipment to conduct a necropsy near Lynnhaven Beach, Virginia.
Multimedia
Humpback whales swimming underwater. Credit: Kogia.org
Pair of bottlenose dolphins. Credit: NOAA Pacific Islands Fisheries Science Center/Lisa Morse.
Research
Publications by Northeast Passive Acoustics Branch Staff
We regularly publish their findings in scientific journals and Center-produced documents.
Passive Acoustic Research at the Southeast Fisheries Science Center
The Passive Acoustic Ecology Program conducts a variety of research projects that use passive acoustics to assess populations and improve our understanding of cetaceans in the Gulf of Mexico and U.S. waters of the Western Atlantic.
Passive Acoustic Technologies Used at the Southeast Fisheries Science Center
Researchers use advanced technology to record and study the sounds produced by marine mammals and human-made sources.
Passive Acoustic Research in the Atlantic Ocean
Marine mammals and many fish produce and receive sound in the ocean. In an environment where vision is limited, hearing is one of the most important senses. These animals rely on sound for navigating, socializing, establishing dominance, attracting…
Understanding Sound in the Ocean
Levels of underwater noise from human activities—including from ships, sonar, and drilling—have increased dramatically.
