The sky is broad, the land is rugged, and the air fills your lungs with joy. But for many adventurers, the true appeal of a trek through a national park is the fine detail: the living flora and fauna often rare and unusual that quietly populate the landscape.
U.S. national parks are each home to an average of 415 species of wildlife—often hundreds more—and over a thousand different plants. Yet there’s not really such a thing as the average national park. Each has its unique characters, families, sights, and sounds. From tiny but tough pikas to trumpeter swans and Dutchman’s breeches, these wild expanses are full of surprises.
So where are most of those surprises found? A recent report from vacation rental site Casago analyzed National Park Service data to find out which parks have the most wildlife and plants per 100 km² (38.61021585 square miles) and which have the greatest biodiversity overall.
Casago sourced the number of species of amphibians, birds, fishes, mammals, and reptiles in each national park from the National Park Service’s Integrated Resource Management Applications (IRMA) portal. They combined the figures to give the total number of animals overall and per 100 km² in each park and calculated additional figures just including birds. And then they did the same for plant species.
- Congaree in South Carolina has the greatest density of wildlife species with 362 per 100 km²
- However, Biscayne in Florida has more overall: a total of 1,002
- Carlsbad Caverns in New Mexico boasts 194 bird species per 100 km², the highest density
- Cuyahoga Valley in Ohio has the densest plant biodiversity of all at 935 species per 100 km²
- The Great Smoky Mountains in North Carolina and Tennessee have the highest number of plant species overall: 2,278.
1. Congaree National Park, South Carolina
Number of species per square kilometer: 362
Life of all kinds from tiny synchronous fireflies to 160-foot-tall loblolly pines crowds this park’s bottomland hardwood forest ecosystem 18 miles from Columbia, South Carolina’s capital. Congaree is also laced with rivers and lakes that sustain its astonishing biodiversity.
Paddling the Cedar Creek Canoe Trail is a great way to look for wildlife. Most commonly you see what we call the creepy-crawlies including fishing spiders with leg spans wider than your palm and red-bellied water snakes. Other residents you might encounter include barred owls, river otters, pileated woodpeckers, and sometimes, alligators gliding on the water.
2. Cuyahoga Valley National Park, Ohio
Number of species per square kilometer: 317
Located 20 miles southwest of Cleveland, Ohio, Cuyahoga Valley National Park is a mixed ecosystem of oak-hickory forest, meadows, and wetlands sheltering a variety of animals. From the boardwalk at Beaver Marsh watch for water-loving mammals (river otters, muskrats, beavers) or snapping turtles that can weigh as much as 55 pounds each. It’s neat to see the old-timers covered in moss.
More than 200 bird species live or migrate through the park including nesting peregrine falcons (near the Route 82 Bridge) and bald eagles (hike the Towpath Trail north from Station Road Trailhead). Check the park website for occasional birding walks or ranger talks.
3. Carlsbad Caverns National Park, New Mexico
Number of species per square kilometer: 286
The poster child for Carlsbad Caverns is the Brazilian free-tailed bat. Every summer, hundreds of thousands of the furry, big-eared creatures roost in these honeycombed limestone caves in southeastern New Mexico attracting crowds at sunset with their spectacular outflight. But it’s just as exciting to come just before dawn and watch the bats return; the bats tuck their wings and execute speedy dives back into the caverns.
The Brazilians are one of 17 bat species that nest at Carlsbad. You might also encounter ringtails (a small, raccoon-like mammal), porcupines, peccaries, and cave swallows.
4. Pinnacles National Park, California
Number of species per square kilometer: 255
Driven to the brink of extinction in the 1980s, the mighty California condor now soars again over this landscape of twisty volcanic peaks in central California. Intense recovery efforts including a captive breeding program and the establishment of two distinctive wild-flying populations have brought the population of the largest birds in North America from just 22 in in 1982 to 347 condors today.
Eighty-nine of the birds are thought to live in and around Pinnacles. If you have binoculars, you have a good chance of seeing condors flying over the ridge behind the main campground in the mornings and evenings.
Other Pinnacles standouts include golden eagles, peregrine falcons, an exceptionally high density of prairie falcons, and more than 400 species of bees.
5. Acadia National Park, Maine
Number of species per square kilometer: 242
The Atlantic Ocean meets the cliff-lined Maine coast at this popular park on Mount Desert Island providing habitat for wildlife with feet and flippers. From the shore or a sea kayak (try Castine Kayak Adventures or Coastal Kayaking Tours) scan the water for the dorsal fins of harbor porpoises and the sleek heads of harbor and gray seals.
On land, you might spot beavers, snowshoe hares, or if you’re lucky a mink or bobcat. In between in the intertidal zone tide pools hold translucent anemones, sea urchins, snails, and sea stars. Acadia also draws loons and songbirds and fall, rangers and volunteers conduct an annual hawk watch from Cadillac Mountain, Acadia’s highest point.
6. Wind Cave National Park, South Dakota
Number of species per square kilometer: 235
Located at the edge of South Dakota’s Black Hills National Forest this park may be best known for its unique boxwork cave geology. But wildlife watchers also come for the herds of American bison, elk, and pronghorns grazing above on the mixed-grass prairie.
Wind Cave is part of an ecosystem restoration and species recovery program that’s been going since the early 20th century. Populations of all three ungulates have rebounded since then and in 2007, biologists also returned the critically endangered black-footed ferret to the grasslands. Drive the 3.7-mile Bison Flats Road or hike the steep, challenging Boland Ridge Trail for the best chance to see animals.
7. Dry Tortugas National Park, Florida
Number of species per square kilometer: 223
Contrary to its name, water makes up 99 percent of this park located on and around a seven-island archipelago some 70 miles off the coast of Florida. Visitors must catch a seaplane or ferry from Key West to get to this remote part of the Florida Keys but they’re rewarded with excellent coral reef and seagrass habitats.
The part of the park’s name that does make sense: Five species of threatened or endangered sea turtles (Tortugas in Spanish) nest here; visitors might see them swimming or on the sandy beaches.
Book a snorkeling or scuba diving excursion to explore the reefs where green sea turtles, nurse sharks, barracudas, and decorator crabs live amid elkhorn and staghorn corals. Divers can also access the Windjammer wreck site where an iron-hulled ship that sank in 1907 provides a home for marine life.
8. Black Canyon of the Gunnison National Park, Colorado
Number of species per square kilometer: 219
In western Colorado, the 2,722 vertical feet between this sparsley visited park’s canyon rim and the Gunnison River below support multiple wildlife habitats. Experienced climbers and hikers who venture into the inner canyon, find collared lizards and mule deer near the rim and bighorn sheep scampering along the middle of the cliffs. Trails are extremely steep, covered with poison ivy and require a wilderness permit to use.
It’s easier to access the Gunnison River by driving down East Portal Road where anglers fish for brown and rainbow trout and nature-lovers might run into river otters and ringtails.
9. Mammoth Cave National Park, Kentucky
Number of species per square kilometer: 217
Located in central Kentucky this national park holds the longest known underground cave system in the world. Mammoth’s 426 miles of caverns are home to 160 species from animals that merely visit (think bats) to those that can’t live anywhere else. Long-legged cave crickets pick their way up the walls, eerily eyeless white cave fish swim the underground waterways, and black-spotted orange cave salamanders lurk under rocks.
If you’re going into the cave system, stop and slowly look around. You might see some of the small, inconspicuous vertebrates that are thriving in complete darkness.
10. Bryce Canyon National Park, Utah
Number of species per square kilometer: 215
The glowing orange hoodoos and rocky walls of Bryce Canyon National Park might seem stark but the arid Utah landscape teems with life. Scan carefully for short-horned and side-blotched lizards basking among the boulders and look out for the venomous Great Basin rattlesnake under the canyon rim.
Small, furry mammals like the golden-mantled ground squirrel, Uinta chipmunk, and Utah prairie dog are easy to see throughout the park but you’re less likely to spot larger predators such as mountain lions and black bears.
Take only memories
A wildlife trip to a national park makes for a welcome alternative to urban life and the computer screen. But to stand your best chance of spotting some gems and avoiding harm to the park’s natural life, leave no trace.
- People only, no pets
- Keep quiet and stay still where possible
- Dress in natural tones and don’t wear scent
- Keep your distance and never feed wildlife
- Take only memories (and photos); leave only footprints
- And don’t forget to look at the clouds
Nature is a mutable cloud which is always and never the same.
—Ralph Waldo Emerson