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
A Cuvier’s beaked whale (Ziphius cavirostris) cruises just under the surface after having taken a breath. NMFS MMPA Permit No.21938. Credit: NOAA Fisheries/Richard Holt.
Southern Resident killer whale J16 breaches near San Juan Island in Washington while J26 swims nearby.
Credit: NOAA Fisheries
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.
