A Paddler’s Guide to the Seals of Maine

July 18, 2024

A closer look at the most commonly spotted marine mammal on the Maine coast

If you’ve been on the ocean in Maine, whether by paddle, oars, motor, or sail, you’ve probably spotted at least one seal. But did you know that Maine is home to four different kinds of seals? Some of these blubbery creatures live in our local waters year round, while others are only seasonal visitors. Read on to learn more about Maine’s most beloved marine mammals!

What Makes a Seal a Seal

Seals are pinnipeds – a group of mammals that also includes walruses and sea lions. All of Maine’s seals are members of the True Seal family (Phocidea in latin). True seals are also called earless seals (because of their smooth round heads), or crawling seals, because of the way they scoot themselves flat across the land. This differentiates them from the eared or walking seals (sea lions and fur seals of the Otariidae family) who possess visible ear flaps and waddle with the front of their bodies held upright when on land. When in the water, true seals propel themselves using their hind flippers, while the front flippers are used for steering and stability. The opposite is true of eared seals.

The skeleton of a Harbor Seal

Like other marine mammals, seals breathe air, but spend most of their time in the water. Unlike dolphins, whales, or manatees however, seals are able to come up on land. In fact, they do so regularly to rest, sunbathe, and avoid predators. A colony of seals perched on one of Maine’s numerous rocky ledges is the most common way to view them. Seals eat a wide variety of fish, crustaceans, and shellfish as their primary foods, but have also been known to eat seabirds and other marine mammals on rare occasions. Just like cats and dogs, they are members of the order carnivora, and people are often surprised by how closely their skeletons resemble these distant cousins (since most of their limb bones are hidden inside their blubbery bodies). Their closest relatives within carnivora are the mustelids, such as weasels, otters, minks, ferrets, and skunks.

Juvenile harbor seal, aka a “Sea Dog”!

Harbor Seals

The most common seal in Maine (and the entire world) is the harbor seal. Harbor seals are identified by their small round heads, large eyes, and short snouts. They are often referred to as “sea dogs” or “sea pups” because of their similarity in appearance to a Labrador Retriever and their curious attitude. Harbor seals pup in spring or early summer, then spend the rest of the summer gathered in colonies as the babies grow and put on layers of blubber. In the winter they separate and will live either solitarily or in small family groups. When not basking on rocks, harbor seals are most likely to be seen popping up a few boat lengths behind or beside a paddler, in order to check out those strange-looking crafts. Harbor seals mainly eat fish, crustaceans, and shellfish, and adults reach an average length of five to six feet, weighing anywhere from 150 to 400 lbs. As for coloring, they tend to be a mix of brown and gray, with speckling of different colors and shades, which gives them a thoroughly mottled appearance.

Close up of a grey seal

Gray Seals

The larger of our two year-round pinnipeds, gray seals can be seven to eight feet long and weigh up to 800 lbs! Gray seals pup in January and February, and pups are born with a soft layer of white fur, which they shed after about a month. The winter pupping season means gray seal babies are more mature by the time most boaters are on the water. Gray seals are most easily distinguished from harbor seals by their size and by their longer snouts, which give them a more horse or cow-like appearance. And, they can dive the longest of any Maine’s seal species – able to stay underwater for up to a hour!

For information about recent gray seal pup rescues in Cape Elizabeth, check out MMoME’s facebook page!

Radio tagging data shows the travels of three different Gray Seals from their place of birth – Map by Kimberly Murray, from NOAA research permit #21719

Harp Seals

Adult harp seal

Harp seals are distinguished by the dark harp-shaped marking on adults’ backs, and by the mask-like patch of dark fur on their face. Juvenile pups are referred to as “beaters”, and are cream with brown spotting. One of two of Maine’s “ice seal” species, they spend their summer in arctic waters, then move south as pack ice forms, where they will give birth on ice flows in late winter or early spring. They regularly migrate thousands of miles, and can be found as far south as Maritime Canada and the Gulf of Maine during the winter.

Juvenile harp seal or “beater”: named for the sound their tails make on the surface of the water

The harp seals seen in Maine are typically members of the Western Atlantic group, which breed off the coast of Newfoundland and Labrador and around Magdalen Island in the center of the Gulf of St. Lawrence.

One of the things which makes harp seals unusual is their weaning process. Pups nurse with their mother for only up to twelve days, at which point they are abruptly abandoned entirely. Pups will stay on pack ice for four to six weeks, while eating nothing at all, until eventually entering the water and learning to feed themselves. After weaning their pups, female harp seals join males at the breeding colony, where they will mate before migrating north to summer feeding grounds.

Hooded Seals

Perhaps the strangest looking of Maine’s four pinnipeds, hooded seals are named for the large air sacks on the male’s heads. Even without the sacks inflated, hooded seals are very distinct, with mottled white-light gray and black-dark gray fur, and a very wide nose reminiscent of an ape or short-faced dog. Juveniles have a distinct light belly and a silvery-blue back. These seals are much more territorial and aggressively solitary than other seals. Hooded seals are of a similar size to the gray seals, ranging from seven to nine feet long and weighing up to 900 lbs.

Hooded seals

Hooded seals are known to be deep-diving feeders, with dives typically lasting 20 minutes and to a depth of 1900 feet. Another type of ice seal, they mate and give birth on pack ice in March and April, and have the shortest weaning period of any mammal, lasting only 3-5 days! They are the least likely of Maine’s four seals to spot in our waters.

Tips & Guidelines for Seal-Watching

Seals are most often seen resting on shore or popping up out of the water to investigate boaters. When paddling keep your head on a swivel, looking to the sides and behind you, and you might spot a curious seal following your boat. You’ll want to keep your ears open too, because seals will often make a distinct huffing sound as they blow salt water from their nostrils. At a distance, seal heads often look like dark-colored buoys or resting sea birds, but with practice you’ll soon be able to spot the differences. When looking for seals on the land, keep your eyes out for movement, or odd discolorations in the rock. Seals, especially the common harbor seals, have a wide range of possible gray, black, brown, tan, and white colorations. They will also often rest in “banana shape” with their head and tail lifted up off of the rock.

Seals are protected under the Marine Mammal Protection Act, and it is very important that we do not disturb them. Never disrupt seals resting on rocks or beaches. If a seal pops up near you while paddling, stop and watch it or paddle away calmly. Never paddle directly at a seal. It is highly unlikely that a seal will cause you or your boat any harm, but for safety (and because it is illegal to do so), you should never try to touch a seal with your hand or paddle, or try to feed it or otherwise coax it closer.

A harbor seal swimming in the distance

The MMPA requires people to stay at least 50 yards (150 feet) away from seal colonies and beached seals at all times (that’s the length of half a football field, or 10 boats). If the seals are reacting to your presence, you are too close. Moving away, waving flippers, yawning, staring, vocalizing, and eating or chewing rocks and sand are all possible signs of disturbance. And please don’t touch a seal pup, even if it looks abandoned. It’s probably just relaxing in a safe spot while mom fishes nearby. Rest out of the water is important for seals, as it keeps them safe from predators, allows them to build up their blubber reserves out of the cold water, and the sun helps kill potentially harmful bacteria.

What to Do if You Spot a Seal That May Be In Trouble

If a seal appears to be injured or is being disturbed by others, call the Maine Marine Mammal hotline at 1-800-532-9551.

While waiting for the response team, do not approach, touch, pour water on, or in any other way disturb the seal. Your assistance in educating other beach-goers and paddlers to keep their distance is greatly appreciated!

A harbor seal resting on the rocks near Portland harbor and Fort Gorges

Seeing Seals with Portland Paddle

Our daily sunset tours are one of the best ways to see seals in southern Maine June through August! Sea kayaks were originally invented by Indigenous Arctic Peoples such as the Greenland Inuit for seal hunting, and these quiet, sea-worthy crafts give you an up close, seals-eye view of the world.

For those looking for a longer expedition, our half day and full day kayak tours offer paddlers the chance to explore beyond Portland harbor, while our multi-day trips provide an amazing opportunity to see seals and other marine mammals such as whales, porpoises, and dolphins in more remote ocean settings!

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