What Divers Should Know About Harbor Seals

Harbor seals, also known as common seals, are true seals widely distributed along the temperate and Arctic marine coastlines of the Northern Hemisphere. Divers frequently encounter these adaptable pinnipeds in coastal waters across the northern Atlantic and Pacific oceans, as well as the Baltic and North Seas. Their coat varies from brown, silvery white, tan, or grey, often adorned with a unique pattern of spots, and they possess distinctive V-shaped nostrils.

An adult harbor seal can reach an impressive length of 1.85 meters (6.1 feet) and weigh up to 168 kg (370 lb). Females typically outlive males, often reaching 30-35 years compared to the males' 20-25 years. These seals prefer to stay relatively close to shore, frequenting subtidal and intertidal zones. They can be spotted in kelp forests, bays, estuaries, and even coastal rivers where they actively forage in shallow littoral waters. While often observed resting on rocky haulout sites, they are agile and graceful underwater, generally keeping a respectful distance from human activity.