24 of the most endangered animals in the US

NatalieJean/ShutterstockGiant sea bass are critically endangered because of over fishing.

While our planet boasts incredible biodiversity, 99.9% of species that have ever existed on Earth are now extinct.

It was estimated that the earth boasts anywhere between 5.3 million to 1 trillion species. In 2020, the International Union for Conservation of Nature (IUCN) assessed 116,177 species from four categories: vertebrates, invertebrates, plants, and fungi & protists, and a little over 31,000 were considered threatened with extinction.

To find the most imperiled creatures ranging from amphibians to avians, Insider consulted data from the IUCN Red List and the United States Fish and Wildlife Service.

Keep reading to learn about 24 of the most endangered species in the US.

Although extinct in the wild by 1980, the red wolf was reintroduced to North Carolina seven years later by the US Fish and Wildlife Service.

Joanna Wu/ShutterstockRed wolves are identified by the colour of the fur behind their ears and along their necks and legs.

Prior to going extinct in the wild in 1980, red wolves – identified by the reddish fur behind their ears and along their necks and legs – were native to North Carolina, Tennessee, and Texas. In 1987, the United States Fish and Wildlife Service reintroduced the species to eastern North Carolina in an area spanning the Albermarle and Pamlico Sounds.

In adulthood, red wolves weigh an average of 45 to 80 pounds and stand 26 inches at the shoulder.

The red wolf is currently listed as critically endangered by the IUCN.

There are 41 Oahu tree snail species, and all are listed as federally endangered by the US Fish and Wildlife Service.

Anony Shutter/ShutterstockOahu tree snails were once so common that they factored into Hawaiian folklore and songs.

Oahu tree snails – any of 41 species belonging to the genus Achatinella – were once so common on the eponymous island that they factored into Hawaiian folklore and songs. The creatures live at elevations of more than 1,300 feet in mountainous dry to wet forests and shrublands.

The snails – which measure three quarters of an inch and feature varying shell patterns, colours, and shapes – graze on the fungus that coats the surface of native plant leaves. Hermaphroditic in adulthood, they have a long lifespan.

Once prized by collectors, their biggest threat is now habitat destruction and predation by rats and carnivorous snail species.

The Kemp’s ridley turtle is critically endangered.

You Touch Pix of EuToch/ShutterstockDespite their small stature, adult Kemp’s ridley turtles can weigh up to 100 pounds.

Found mainly along the Gulf of Mexico, some Kemp’s ridley turtles swim to the east coast of the United States, including the shore of South Carolina.

Due to the over-harvesting of its eggs, the Kemp’s ridley is one of the world’s most endangered sea turtle species. It’s also the smallest species – adults have a shell length of just two feet. Despite their small stature, these turtles can still weigh up to 100 pounds.

Found in the southern tip of the Sunshine State, there are only 100 to 180 Florida panthers in the wild.

jo Crebbin/ShutterstockPanthers once lived across the southeastern US from Florida to Arkansas.

Panthers were once found across the southeastern US, spanning from Florida to Mississippi to Arkansas. Now, the only known breeding population is in southern Florida, where there are between 120 to 130 of the wildcats left in the wild.

As habitat generalists, panthers – which belong to the same subspecies as pumas, mountain lions, and cougars – are just as likely to live in forests, prairies, and swamps.

The Columbia Basin pygmy rabbit is the smallest rabbit species — and one of the most endangered.

Randy Bjorklund/ShutterstockThe main reason for the rabbits’ decline is the destruction of their sagebrush habitat.

True to its name, the Columbia Basin pygmy rabbit – which weighs less than a pound and measures between 9.3 to 11.6 inches long in adulthood – is the smallest rabbit species. It’s also one of the most endangered. As of 2001, fewer than 50 were found in the wild.

While the species once lived throughout the northwestern United States, its range is now limited to Washington State. The main reason for the pygmy rabbits’ decline is the large-scale destruction of their sagebrush habitat. They rely on sagebrush for both shelter and food.

The Eskimo curlew was last sighted with certainty in 1963 — and some scientists speculate it might already be extinct.

Tom Middleton/ShutterstockEskimo curlews once migrated between breeding grounds in Alaska and Canada and their winter home in Argentina.

Listed as critically endangered on the IUCN Red List, the Eskimo curlew was last seen with certainty in 1963. Some scientists speculate it might already be extinct.

Historically, the birds ranged from breeding grounds in the Alaskan and Canadian Arctic to Argentina’s Pampas grasslands, where they would migrate each winter. One report from the mid-19th century detailed how a flock occupied 40 to 50 acres of ground in Nebraska.

Ramsey Canyon leopard frogs have been found at just five sites in Arizona, including backyard ponds.

Alexander Sviridov/ShutterstockAs habitat generalists, these amphibians thrive in aquatic areas in oak woodlands and semi-desert grasslands.

Native to Arizona’s Huachuca Mountains, extant populations of Ramsey Canyon leopard frogs have been found at only five sites, backyard ponds included. As habitat generalists, these amphibians can thrive in aquatic areas of pine-oak, oak woodland, and semi-desert grassland environments.

Although they’re now protected in California and Mexico, giant sea bass are critically endangered due to over fishing.

NatalieJean/ShutterstockGiant sea bass are found from California’s Humboldt Bay to the tip of Baja California.

Spanning from California’s Humboldt Bay to the tip of Baja California, giant sea bass are critically endangered due to over fishing, and have been listed by the IUCN since 1996.

While juveniles are found at depths of about 40 to 70 feet, where they swim around kelp beds, adults prefer depths of nearly 100 feet.

Staghorn coral has experienced a population reduction of more than 80% over the past 30 years.

John A. Anderson/ShutterstockThis coral species is found in shallow tropical reefs from Florida to Venezuela.

Staghorn coral – found in shallow tropical reef ecosystems from Palm Beach, Florida, to Venezuela – has experienced a population reduction of more than 80% over the past 30 years.

Major threats to the species (and other corals) include disease and climate change.

The Franklin’s bumble bee was last sighted in 2006 by a retired entomologist.

Bachkova Natalia/ShutterstockFranklin’s bumble bee not pictured.

Much of what we know about the Franklin’s bumble bee, which was last sighted in 2006, comes from a retired (and tireless) entomologist named Robbin Thorp. His unpublished reports indicate that populations have decreased drastically since 1998 – to such an extent that not a single one of the bees was spotted between 2004 and 2005.

This rare bumblebee – one of more than 20,000 apian species – is only found between southern Oregon and northern California.

In general, the largest threats to bumblebees include exotic diseases introduced via commercial greenhouses, habitat destruction, and agricultural pesticides.

There are fewer than 250 dusky gopher frogs, which are found only in Mississippi.

Luke P Ferguson/ShutterstockDusky gopher frog not pictured.

It’s estimated that there are fewer than 250 mature dusky gopher frogs, which live in stump holes and burrows in longleaf pine forests. You’ll find breeding adults and tadpoles in shallow, fishless emphemeral, and isolated wetlands.

Once spanning the coastal plain of the southern United States from eastern Louisiana to Alabama’s Mobile River delta, the species is now limited to Harrison County, Mississippi. As of 2003, these frogs have primarily been found in Glen’s Pond in De Soto National Forest.

Like sharks and rays, smalltooth sawfish are members of a cartilaginous group of fish called elasmobranchs.

Reimar/ShutterstockIn adulthood, smalltooth sawfish can weigh up to 770 pounds.

Along with sharks, skates, and rays, sawfish are members of a cartilaginous group of fish called elasmobranchs. The oldest cousin of the sawfish we know today took to the waters 100 million years ago.

The smalltooth, found mainly in the peninsula of Florida, is one of two sawtooth species native to the US. It’s also found as far away as Honduras and Sierra Leone. Measuring between 18 and 25 feet long in adulthood, smalltooth sawfish can weigh up to 770 pounds.

Due to their size, smalltooth sawfish can damage fishing gear and pose a threat to fishermen. When they’re captured by mistake, they’re often killed. Juvenile fish, which live in shallow areas abundant in vegetation (such as mangrove forests), are imperiled by habitat loss.

The Mitchell’s satyr butterfly is found only in Michigan and Indiana, where it lives in rare wetlands known as fens.

Sari ONeal/ShutterstockThe species can be identified by the orange-ringed black circular eyespots on its wings.

Found only in Michigan and Indiana, the Mitchell’s satyr butterfly is restricted to rare wetlands known as fens. It can be identified by its wings, which feature orange-ringed black circular eyespots.

Habitat destruction is the main reason why the Mitchell’s satyr is endangered. Much of its wetland habitat has been drained and filled due to urban and agricultural development. Fens are also susceptible to pollution from pesticides, fertiliser, and other contaminants. Additionally, some populations might have been decimated by butterfly collectors.

Bog turtles are threatened by damage to their wetland habitat. They’re also in demand in the pet trade.

Jay Ondreicka/ShutterstockThere are two separate populations of bog turtles.

There are two separate populations of bog turtles, which live in marshes and swamps in regions ranging from the southeastern Appalachian foothills to western Massachusetts.

The biggest threat to the species is habitat destruction. Bog turtles are also in small but high demand in the pet trade.

California condors nearly perished for good in the 1980s, but an intensive captive breeding program brought them back from the brink of extinction.

Georgi Baird/ShutterstockThe species’ decline has been attributed to lead poisoning and to the reduced eggshell thickness from DDT.

By 1987, California condors – which have historically been found between British Columbia and Baja California – were extinct in the wild. That year, the last six wild members of the species were captured for a breeding recovery program. Thankfully, the program was successful, yielding a population of 223 birds by 2003.

The species’ decline has been attributed to lead poisoning (from the accidental ingestion of bullet fragments stuck in carcasses) and to reduced eggshell thickness related to ingesting the pesticide DDT.

The Ozark hellbender is a large, aquatic salamander found in Missouri and Arkansas.

Jay Ondreicka/ShutterstockThe Ozark hellbender is nocturnal, usually hiding under large rocks during the day.

The Ozark hellbender is a large, aquatic salamander that can survive for up to 30 years in the wild. Found only in southern Missouri and northern Arkansas, the species lives in the White River watershed.

In addition to ore and gravel mining, its habitat is harmed by nutrient and toxic runoff. The Missouri populations are also threatened by an infectious fungus.

The Kanab ambersnail is found only in Utah and in Arizona’s Grand Canyon National Park.

Erik Agar/ShutterstockThe Kanab ambersnail is not pictured.

Kanab ambersnails are an endangered mollusk found in Kanab, Utah, and in Arizona’s Grand Canyon National Park. They utilise wetland vegetation for food and shelter, receding into their shells during the winter.

A hermaphroditic species, these snails are capable of self-fertilisation if they can’t find a mate.

Mississippi sandhill cranes are found only at a wildlife refuge in Jackson County, Mississippi.

Jean Faucett/ShutterstockAround 100 of the cranes live at the refuge.

Critically endangered, Mississippi sandhill cranes are found only at a wildlife refuge in Jackson County, Mississippi, where around 100 individuals remain.

Originally, the population’s range spanned along the Gulf coastal plain from southern Louisiana to the western Florida panhandle. Much of the species’ habitat was destroyed when the open pine savanna was converted to pine plantations following World War II.

The grotto sculpin is found in the caves of Perry County, Missouri.

Silvlandia/ShutterstockThe grotto sculpin not pictured.

The grotto sculpin, a tiny, cave-dwelling fish, is found only in Perry County, Missouri. A federally endangered species, the population is contained to five cave systems and two streams.

Water contamination poses the biggest threat to the species.

The coral pink sand dunes tiger beetle is critically endangered and only found in Utah.

Ferdy Timmerman/ShutterstockThe tiger beetles range from 11 to 15 millimetres in length.

The coral pink sand dunes tiger beetle can only be found in Utah’s Coral Pink Sand Dunes State Park. Its habitat is primarily threatened by offroad vehicles and droughts due to climate change.

While two conservation areas and a ban on offroad vehicles have been established, the species remains critically endangered because of its small range size.

The entire species of the Maui parrotbill is fenced in to prevent threats from feral pigs and deer.

Thipwan/ShutterstockThe bill can be used to split branches and extract larvae.

This endangered species is up against a variety of threats, including feral pigs, deer, hurricanes, and general environmental degradation.

The feral pigs began invading the species’ habitat in 1945 and continued to threaten the parrotbill up until 1995, spreading disease-carrying mosquitos. Now, the Maui parrotbill species are currently living in a conservation area on the Hawaiian island of Maui.

The Florida cave shrimp has only been found in a single limestone cave in Florida and were last seen there in 1973.

Brandon B/ShutterstockFlorida cave shrimp not pictured.

The first Florida cave shrimp were collected in 1953, then again in 60s and 70s, with the last known species recorded in 1973.

Since the cave shrimp are only found in one cave, their ecosystem is expected to face threats as Gainsville, Florida expands. The expansion could impact ground-water quality because of storm water runoff, sewage drainage, and fertiliser use in the area.

The cave shrimp are also threatened by an invasive fish species that have been found in the cave.

The Akohekohe, or crested honeykeeper, is the largest bird of its kind in Maui and is predominantly threatened by deer.

Michael Siluk/ShutterstockThe Akohekohe is not pictured, but also features orange splotches throughout its body and head.

The Akohekohe species lives in the forests of Maui and is threatened by habitat degradation and disease-carrying mosquitos found in the lowlands. Extreme weather as a result of climate change is also a constant threat to the bird.

There are only an estimated 3,800 mature individuals, which places the species on the IUCN’s critically endangered list.

The Razorback Sucker’s population is believed to have declined by 80 per cent over the last three generations.

Helen H. Richardson/The Denver Post via Getty ImagesA USFW Biologist holds holds the rare Razorback Sucker on a recent outing on the Colorado River.

Commonly found in the Colorado River basin, the species ranges from Wyoming to Colorado, and from Sonora to Baja California.

The Razorback Sucker’s species has declined so much because of newly introduced fish species and dams. Whenever stream flow is manually regulated or there is an introduction of pesticides and pollutants, the Razorback Sucker is threatened.

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