Situated at the mouth of Massachusetts Bay, Stellwagen Bank National Marine Sanctuary is one of the planet's best whale watching destinations. Each summer, humpback whales visit these protected waters to feed on sand lance. Experienced scuba divers come to observe life below the surface – schooling fish, sponges, moon snails, clams, wolf eel, sharks and ocean sunfish, among others.
Photo courtesy of Massachusetts Office of Travel & Tourism

The Monterey Bay National Marine Sanctuary was established in 1992 to protect the waters off California's central coast. Encompassing 276 miles of shoreline between Marin and Cambria, the sanctuary protects the country's largest kelp forest where 34 species of marine mammals, 525 species of fish and 180 species of birds live. Nicknamed the "Serengeti of the Sea," the sanctuary is a great place to go tide pooling, whale watching or to spot seals, sea lions and sea otters.
Photo courtesy of Robert Schwemmer

Crystal River National Wildlife Refuge was established in 1983 as the only refuge specifically for the protection of the endangered Florida Manatee. This stunning sanctuary protects undeveloped spring habitat at the headwaters of the Crystal River, where manatees migrate each winter. Visitors can view them from above the water or below, via guided snorkeling tours.
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Although the nene – Hawaii’s endangered state bird, a.k.a. the Hawaiian goose – is emblematic to the Kaua’i refuge, its sheer cliffs and ocean waters are home to a number of fascinating creatures. It boasts large populations of nesting seabirds, plus Hawaiian monk seals and spinner dolphins. Its historic lighthouse punctuates the island’s rugged and dramatic north shore.
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Wildlife enthusiasts flock to Ellie Schiller Homosassa Springs Wildlife State Park to spot the endangered West Indian manatees – the mammals are visible from the park's underwater observatory just about every day of the year. Manatees aren't the only residents; it's also possible to see American alligators, American crocodiles and river otters, as well as a few terrestrial mammals, like black bears, bobcats and white-tailed deer.
Photo courtesy of Tim Donovan/FWC

While the Channel Islands themselves are perhaps most famous for the sly island fox, it's what lies just offshore that makes this national park a wildlife watcher's dream. The Santa Barbara Channel boasts productive waters that attract mega pods of common dolphins, as well as Risso's dolphins, elephant seals, northern fur seals, harbor seals, California sea lions and Pacific gray whales.
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Although most equate “Ding” Darling with serious birding, the Florida refuge is great for aquatic animals as well. The 4-mile Wildlife Drive and its spur trails allow nature watchers to come quite close to American alligators, Florida manatees and nearly 250 species of birds. Its recreation concession offers rentals, lessons and tours by kayak, tram, boat and paddleboard.
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Located northeast of Naples, the Corkscrew Swamp Sanctuary protects a swathe of Everglades ecosystem where it's possible to spot alligators, otters and red-bellied turtles, along with a wide variety of bird life. A boardwalk trail winds through the sanctuary, providing excellent viewing and photography opportunities.
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The second largest national park in the contiguous US, the Everglades covers more than 1.5 million acres. It's a fantastic place to view different species in their natural habitats: tropical fish, colorful birds, giant tree snails, and an array of reptiles and amphibians. In fact, this preserve is the only place in the world where alligators and crocodiles share a habitat.
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The waters of Puget Sound and the San Juan Islands boast a staggering array of animal life. Visitors to the second largest estuary in the United States can often spot orcas, sea lions, harbor seals, sea otters, gray whales and humpback whales, as well as hundreds of bird species.
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