Seals and sea lions belong to a group of marine mammals called pinnipeds, which means fin or flipper-footed. These animals live in the ocean, but are able to come on land for long periods of time. Some species have evolved the ability to hold their breath for up to two hours and dive to depths of more than 6,500 feet when looking for food.
There are two families of pinnipeds: Phocids and Otariids. Phocids are also known as earless seals or “true” seals. They have ear holes, but no external ear flaps. They also have small front flippers and move on land by flopping along on their bellies. At sea, these seals move their rear flippers back and forth like a fish's tail to propel themselves through the water. Phocids include the harbor seal and Hawaiian monk seal.
Otariids, also known as eared seals, include sea lions and fur seals such as the Steller sea lion and the northern fur seal. Unlike true seals, they have external ear flaps. Their front flippers are large, and on land, they are able to bring all four flippers underneath their bodies and walk on them. Otariids propel themselves in the water by paddling their front flippers and using their rear flippers to steer.
All seals and sea lions 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 unique marine mammals and their habitats.
Species News
A new study has classified the North Atlantic right whale stock as very highly vulnerable to climate change. Credit: NOAA
Gray seal swimming in a Beverly, Massachusetts pond. Photo Credit: Seacoast Science Center
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.
Healthy harbor seals in a tide pool along the coast of Washington State. Puget Sound seal populations are considered healthy. Credit: Sophie McCoy, UNC
Multimedia
Humpback whales swimming underwater. Credit: Kogia.org
Pair of bottlenose dolphins. Credit: NOAA Pacific Islands Fisheries Science Center/Lisa Morse.
Research
First Demographic Parameter Estimates for the Mediterranean Monk Seal Population at Madeira, Portugal
We provide the first comprehensive demographic assessment of the Endangered Mediterranean monk seal…
Publications by Northeast Passive Acoustic Research Staff
Our staff regularly publish their findings in scientific journals and Center-produced documents.
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…
Protected Species Gear Research
We work closely with the commercial fishing industry to reduce harmful interactions with marine mammals, turtles, and other protected species.
Viewing Marine Life
Watching marine animals in their natural habitat can be a positive way to promote conservation and respect for animals and their environment.
