Part of the Oregon Islands National Wildlife Refuge, Simpson Reef, Shell Island, and the surrounding rocks and reefs are the largest haul-out for marine mammals on the Oregon Coast. Due to the reefs and islands are breeding and resting areas for sea lions, seals, and seabirds, they are closed to public access at all times.
Because of the gradual slope of the offshore rocks and sandy beaches, Simpson Reef is a great location for seals and sea lions to haul out of the ocean.
Viewpoints are available at Cape Arago State Park, Shore Acres State Park, and along hiking trails. Constructed in 2003 at the end of Cape Arago Highway (North Cape Arago State Park), Simpson Reef Overlook provides a great opportunity to view and take photos.
Region: South Oregon Coast • USA
Operated: Oregon State Park
Access allowed: No
Viewpoints along Cape Arago Hwy
Sunset Bay State Park campground
Dogs: Must be on a leash
GPS Coordinates: 43.314157, -124.403904
Pinnipeds (Seals and Sea Lions) of Simpson Reef & Shell Island
Northern Elephant Seals (lack visible ear flap) are the deepest diving and the largest sea mammals. Males can weigh over 5,000 pounds (over 2,200 kilograms) and are up to 13 feet (4 meters) in length. Females weigh less than 1,000 pounds. They are gray or tan in color without any spots.
Shell Island is the northernmost breeding site of the elephant seals on the Pacific coast. They are winter breeders and pups can't survive in the water for 8-10 weeks after birth. Because of winter storms northern elephant seals' pups rarely survive.
Harbor Seals (lack visible ear flap) are the smallest seals at Cape Arago. Mature males and females are similar in size, ranging from 150 to 300 pound (70-136 kilograms), and 5-6 feet (1.5-1.8 meters) long. They occur in wide variety of grays with dark spots. Harbor seals give birth at Cape Arago in April and May and nurse three weeks. Young harbor seals can swim at birth.
Steller or Northern Sea Lions are the sea lion family. Mature males can weigh up to 2,400 pounds (over 1,000 kilograms) and are about 10 feet (3 meters) long. Females are 700 pounds (317 kilograms) and 7-8 feet (2-2.4 meters) in length. Sea Lions have visible ear flaps and can turn their hind flippers under body which allows then to walk when on land. They are yellowish-brown with dark brown flippers and have a deep load roar.
The Steller sea lions are summer breeders but they don't breed at Cape Arago. They use rocks of Simpson Reef and Shell Island as a haul-out site. One of the breeding sites in Oregon is Sea Lion Caves in Florence.
California Sea Lions are easily identified by noisy barking. Only males migrate to Cape Arago during late summer and fall. Females and their pups remain in California. Mature males weigh over 500-700 pounds (227-318 kilograms) and grow to 8 feet (2.4 meters) long. Females weigh 200 pounds (90.1 kilograms) and 6.5 feet (2 meters) in length. They are brown in color, and males with age develop light tuft of fur on their head.
California Sea Lions breed in California in the summer months. After breeding, males migrate north and use the Cape Arago area as a haul-out site from late summer to spring. Females with pups remain in California.