Seals are present in New Jersey, utilizing the state’s coastline as a temporary home during the colder months. These marine mammals are seasonal visitors, migrating south from their northern breeding grounds in New England and Canada to forage and rest. New Jersey waters offer a suitable stopover point, providing rich feeding grounds and sheltered locations for these animals to recover energy.
Identifying the Seal Species in New Jersey
The most commonly observed pinniped along the Jersey Shore is the Harbor Seal (Phoca vitulina), which accounts for the vast majority of sightings. These seals have a relatively rounded head and a short, dog-like snout, with their nostrils forming a distinctive V-shape when viewed head-on. Adult Harbor Seals reach lengths of about five to six feet and can weigh up to 285 pounds. Their coats vary in color, ranging from silver-gray to light tan or brownish-black, often covered in dark speckles or spots.
Other species are seen less frequently but make appearances during the winter season. The Gray Seal (Halichoerus grypus) is a larger visitor, known for its long, horse-like head and broad arching snout. Adult males of this species are significantly larger than females and can be distinguished by their darker coats and thicker necks.
Occasional sightings also include the Harp Seal and, rarely, the Hooded Seal. Harp Seals, particularly juveniles, are sometimes seen; adults are silver-gray with a black face and a wishbone-shaped pattern on their back.
Seasonal Presence and Preferred Habitats
Seals are primarily winter residents in New Jersey, present from late fall (around November) through early spring (typically concluding by April). Their migration is driven by the availability of food sources and the need to avoid harsher winter conditions farther north. During this period, the seals feed on fish, squid, and crustaceans found in the nutrient-rich coastal waters.
The seals’ primary activity on land is termed “hauling out,” when they leave the water to rest, regulate body temperature, and digest food. They seek isolated, undisturbed locations for this behavior, often preferring sandbars, exposed rocks, and secluded beaches. Significant haul-out sites are found along the northern coast, particularly in the Sandy Hook Bay area, including sandbars near Skeleton Island.
Seals also use the mouths of major waterways, such as the Delaware Bay and various river inlets, as resting areas after foraging. Sightings along the coast become less frequent as water and air temperatures rise, signaling their return migration north to breeding and molting grounds. Low tide often offers the best opportunity for viewing seals, as more sandbars and rocks are exposed for them to rest upon.
Federal Protection and Responsible Viewing
All marine mammals, including seals, are legally protected by the Marine Mammal Protection Act of 1972 (MMPA). This legislation makes it illegal to harass, feed, or injure the animals. Harassment is defined broadly and includes any act that has the potential to injure a marine mammal or disturb its natural behavioral patterns, such as resting or feeding.
To avoid causing disturbance, the public is required to maintain a distance of at least 150 feet from any seal observed on the beach or shore. Approaching closer than this can cause the seal to become stressed and prematurely return to the water, expending energy it needs for survival. Signs that a seal is being disturbed include vocalizing, repeatedly looking at the person, or moving its flippers.
It is important to secure pets and keep them far away from hauled-out seals, as interactions can be harmful to both animals. If a seal appears to be injured, entangled, or in distress, people should not attempt to assist it themselves. Instead, immediately contact the Marine Mammal Stranding Center’s 24-hour hotline at 609-266-0538 for professional assistance.