The animals of North America include some of the most diverse species in the world. They are of all different sizes, shapes, colors, and speeds.
Here is a list of the ten slowest animals in North America, starting at the short, slow end and working down to some of the slowest creatures on the continent, perhaps in the world.
10. Swallowtail Butterfly
Swallowtail butterflies are a group of insects belonging to the family Papilionidae. This family comprises about 560 butterfly species, with different species living all over North America. Their name derives from their appearance, especially the pointed tips of their hind wings, which resemble that of the swallow bird.
Swallowtail butterflies can be brightly colored or have darker wings with light spots. Their natural appearance can mimic that of poisonous species for protection.
Their wing-beat speed, the slowest of all insects, makes them one of North America’s slowest animals. This allows the swallowtail to feed on its most common foods, which in the case of the Eastern Tiger Swallowtail (Papilio glaucus), include lilac, wild cherry, and milkweed nectars.
Compared to a midge fly (several species of the order Diptera), which is 62,760 beats per minute, the swallowtail butterfly’s wings flap at only 300 beats per minute.
The manatee is one of the slowest-moving mammals on the North American continent. The Florida Manatee (Trichechus manatus latirostris) is a subspecies of the West Indian Manatee (Trichechus manatus) and inhabits coastal areas including Florida, the Gulf Coast, and the Eastern Seaboard, up to Massachusetts.
These animals can grow from eight to thirteen feet in length and weigh as much as 1,300 pounds. Historically, the manatee likes to inhabit warm waters, generally attracted to warm natural springs.
The manatee is currently attracted to warm-water outflow from power plants and other human-made sources. Unlike other animals, manatees have lungs along their backs, which expand and contract to give them varying buoyancy degrees.
Though they can swim in short bursts up to 15 miles an hour, this elephant relative generally swims at slower rates. Grazing on seagrass and other marine plants, manatees gently float at 4.8 to 8 km/hr (3 to 5 miles per hour).
8. Rosy Boas
The Rosy Boa (Lichanura trivirgata) is a snake species that is one of the United States two native boas. Dwelling in the American Southwest and the states of Sonora and Baja, Mexico, these snakes are used to staying out of the sun under rocks and in caves.
They are usually seventeen to forty-four inches long and have a round, smooth body in varying shades of brown, orange, gray, and even blue.
Feeding on small birds, snakes, lizards, amphibians, and rodents, the Rosy Boa kills by constricting its prey. It can strike quickly, but its average crawling speed is about 1.6 km/hr (1 mile per hour), making it one of the slowest snakes in the world.
7. Gila Monsters
The Gila Monster (Heloderma suspectum) is another reptile that lives in the American Southwest and the Sonoran Desert. However, it can also live in the mountains, at elevations up to five thousand feet.
This roughly two-foot-long lizard weighs about four pounds and has a distinctive black-and-orange (or yellow or pink) pattern. Though it favors the rocky outcroppings of desert foothills, it spends significant time underground.
It only comes to the surface of the sun itself, albeit rarely. A venomous lizard (though not harmful to humans), the Gila Monster feeds on bird eggs and small newborn mammals.
It has a low metabolism, resulting in the reptile’s large size. A Gila Monster can consume the calories it needs for a year in three or four large meals. Still, it manages a pace of 1.6 km/hr (1 mile per hour), matching the Rosy Boa.
Starfish belong to a large genus called Asteroidea, which contains over 1,500 starfish species worldwide. In North America, starfish inhabit both coasts — from the Northwest Pacific-dwelling Pink Sea Star (Pisaster brevispinus) to the Atlantic’s Common Sea Star (Asterias Rubens).
Typically, starfish live in rocky shallows or gravel-laden parts of deeper waters. They are generally carnivorous and tend to eat stationary bivalves like oysters, clams, and mussels, with some species extending their stomach far beyond their mouth.
As many species do not need to travel quickly to feed or mate (males and females typically release spores into the water), starfish have evolved to be sedentary creatures, often traveling at speeds of 0.096 km per hour (0.06 miles per hour).
5. Desert Tortoises
Desert tortoises are a few reptile species common in the Mojave and Sonoran deserts (Southern California, Nevada, Utah, Arizona, and Northwestern Mexico). They grow to about nine to fifteen inches in length and can weigh as much as fifteen pounds.
Desert tortoises are two species, Gopherus agassizii and Gopherus more kai, living west and east of the Colorado River, respectively. They have a complex, high shell, domed in shape, and can withdraw their limbs entirely underneath it.
Feeding on cacti, grasses, and wildflowers, desert tortoises do not need to move fast to capture prey or run away from predators. Often burrowing underground for cover, these animals have a walking speed of only 0.05 km/hr (0.03 miles per hour).
4. Garden Snails
Whether you consider it a garden pest or a delightful delicacy, the garden snail (Cornu aspersum) is one of North America’s slowest gastropods. Existing on the continent entirely as an introduced species, this species inhabits Canada, Mexico, Haiti, Martinique, and large parts of the United States.
Garden snails have a distinct shell of 1.1 to 1.7 inches in diameter and typically feed on flowers, plants, and shrubs; they also particularly favor citrus plants and fruit.
Their bodies are lined with mucus to trap moisture in, and though their shells provide some protection, they are often prey to insects, lizards, amphibians, and birds. On average, they travel at a rate of 0.047 km/hr (0.029 miles per hour).
Insects find their mates in some unique ways. Please find out more in this article I wrote.
3. Banana Slugs
The banana slugs are several species that belong to the genus Ariolimax. These gastropods can grow up to 9.8 inches and are usually yellow, though they can be white, tan, or greenish.
They live on the Pacific Northwest’s damp forest floors (from Alaska to Northern California) and feed on dead organic matter, moss, fallen plants, and animal feces. With bodies mostly of water, these slugs secrete mucus to retain moisture.
The mucus also has the added benefit of being bad-tasting to predators. As members of Ariolimax only have one lung and one foot, their speed is minimal, clocking in at 0.0098 km/hour (0.0061 miles per hour).
2. The Dwarf Seahorse
The Dwarf Seahorse (Hippocampus zosterae) is considered the slowest fish in existence (by the way, starfish are not fish). They are also one of the world’s tiniest seahorses, about 1 inch in length.
This species inhabits grassy seabeds of the Gulf Coast, the Caribbean, and the eastern coast of Florida. They swim by propelling themselves with their dorsal fins and steering with their pectoral fins. This results in an upright mobile position, one that is used to eat copepods, small shrimp, and very tiny fish.
Mating behaviors are like many seahorse species, in which fertilized eggs are kept inside the male’s pouch to brood for 11 days. The Dwarf Seahorse lives among floating vegetation and can afford to travel at slow speeds, about 0.0015 km/hour (.00093 miles per hour).
1. Sea Anemones
Sea anemones are animals that belong to the scientific order Actiniaria. They are closely related to jellyfish, corals, and water-dwelling animals known as hydra.
Like many corals, sea anemones are polyps that attach to hard surfaces — and have tentacles and mouths with which they sting and consume their prey (usually crabs, plankton, or tiny fish). They also have symbiotic relationships with green algae known as zooxanthellae. The algae provide the anemone with glucose and amino acids, and the anemone includes carbon dioxide and other plant-sustaining nutrients.
Over 1,000 sea anemones worldwide, with species like the Sunburst Anemone (Anthopleura sola) inhabiting the Pacific Northwest and the Giant Anemone (Condylactis gigantea) living in the Caribbean and off the Mexican and Floridian coasts.
Sea anemones can “glide” very slowly along their chosen surfaces or detach from them completely to fasten onto other surfaces. They move at an astonishingly slow 1.016 e-6 km/hr (0.04 inches per hour) — that’s 0.000001016 km/hr (0.000000631 miles per hour), making them the slowest animals on our list.
Bryan Harding is a member of the American Society of Mammalogists and a member of the American Birding Association. Bryan is especially fond of mammals and has studied and worked with them around the world. Bryan serves as owner, writer, and publisher of North American Nature.