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
Southern Resident killer whale preys on salmon in the Salish Sea near Seattle. Credit: Su Kim/NOAA Fisheries
Hawaiian monk seal RK96 and her pup rest in Waikīkī. Credit: Hawaii Marine Animal Response.
A harbor seal pup is assessed for body condition and signs of injury. Credit: WDC
Southern Resident killer whale L47, also known as Marina, was born in 1974, just after the last commercial captures of the now-endangered population. Credit: Jeanne Hyde/The Whale Museum
Research
Marine Mammal Research Surveys in NOAA’s Southeast Region
How survey data is collected and used to inform marine mammal population assessments in the Southeast.
Marine Mammal Life History
Data collected from stranded and bycaught marine mammals are critical to understanding their life history
Understanding Sound in the Ocean
Levels of underwater noise from human activities—including from ships, sonar, and drilling—have increased dramatically.
