Vulnerable Species

Updated: December 26, 2021
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Vulnerable species are at risk of becoming extinct in the wild or extinct. The IUCN currently identifies over 10,000 species as vulnerable. For a species to be considered vulnerable it must meet any of the following criteria:

Population Reduction

  • A taxon’s population size is reduced by 50 percent or more over 10 years or three generations, whichever is longer, and scientists understand that the reduction causes are reversible and have stopped. For example, let’s pretend there is a bird species that traditionally had a population of 2000. Over 10 years, it drops to 1000 because a logging company demolished its habitat. If lawmakers establish regulations that bar the logging company from continuing to fell trees in the area, then the IUCN will list the bird species as “endangered” because they understand the reason for the decline, and it is stopped.
  • A taxon’s population size is reduced by 30 percent or more over 10 years or three generations, whichever is longer. However, conservationists don’t understand the reduction cause or know if it is reversible. For example, let’s say there is a bird species that traditionally had a population size of 2000. Over 10 years, it drops to 1400. Scientists, however, can’t figure out why they’re dying off. In this case, the IUCN would list it as “endangered” because the decimation is evident, but it can’t figure out why.
  • A taxon’s population size is reduced by 30 percent or more over 10 years or three generations, whichever is longer, and the animal is also battling habitat shrinkage or another threat.

Geographic Reduction

The area where a species can live is reduced to 20,000 square kilometers or less, or the area where it currently and actually occupies is reduced to 2,000 square kilometers, and at least two of the following criteria are also true:

  • The population is not known to exist at more than 10 locations.
  • Scientists observe or predict that the habitat in question will continue to shrink or be degraded, and there’s also a decline in subpopulations or the number of reproducing adults.
  • Scientists observe extreme fluctuations in the number of locations, subpopulations, or the number of reproducing adults.

Dangerously Low Number of Adults

  • A taxon’s population only has 10,000 or fewer adults left, and a 10 percent decline is anticipated within 10 years or three generations, whichever is longer. If none of the taxon’s subpopulations contain more than 1,000 adults, or all the adults live in one subpopulation.
  • Scientists observe extreme fluctuations in the number of mature adults in a taxon’s population.

Dangerously Low Overall Population Size

Only 1,000 or fewer individuals of a taxon remain.

A population with a viable but restricted habitat area is vulnerable to human activities within a very short period and thus may become critically endangered or extinct in the near future.

Expected Rapid Decline

Research indicates that there’s a 10 percent or greater chance that the taxon will be extinct in the wild within 100 years

Vulnerable Species

A African Golden Cat
African Golden Cat

The first image of an African golden cat was captured in the wild in Gabon in 2002.

A Aldabra Giant Tortoise
Aldabra Giant Tortoise

One got to be 255 years old!

A Apennine Wolf
Apennine Wolf

Wolves do not howl at the moon. They howl to communicate with other members of their pack.

A Asian Carp
Asian Carp

Asian carp can consume 40% of their body weight in food a day!

A Asian Palm Civet
Asian Palm Civet

It mainly eats mangos and coffee!

A Babirusa
Babirusa

Babirusas can stand on their back hooves to eat leaves on the lower branches of a tree.

A Baleen Whale
Baleen Whale

“Sings” a whale song during breeding season.

A Banded Palm Civet
Banded Palm Civet

Markings give it camouflage!

A Beauty rat snake
Beauty rat snake

Beauty Rat Snakes are relatively harmless if left undisturbed, only attempting to bite out of fear.

A Bhutan Takin
Bhutan Takin

Live in bamboo forests 15,000 feet above sea level

A Bilby
Bilby

In Australia, the chocolate bilby replaces the chocolate bunny for Easter.

A Binturong
Binturong

Also known as the Asian Bearcat!

A Bird Snake
Bird Snake

Usambara vine snakes sit perfectly still and sway in the wind like a stick.

A Blacktip Reef Shark
Blacktip Reef Shark

They move in and out of mangrove swamps with the tides.

A Box Turtle
Box Turtle

This reptile has an S-shaped neck allowing it to pull its entire head into its shell.

A Bull Trout
Bull Trout

The bull trout is not actually a trout, but a member of the char family.

A Burmese Python
Burmese Python

These snakes can swallow their prey as whole.

A Cantil
Cantil

Cantils heads are marked with bright white lines on each side of their heads.

A Capuchin
Capuchin

Named after Capuchin friars.

A Caribou
Caribou

Males and females grow antlers

A Cheetah
Cheetah

The fastest land mammal in the world!

A Chinese Cobra
Chinese Cobra

Juvenile Chinese cobras have the ability to start hunting almost from the moment they hatch from the eggs.

A Clouded Leopard
Clouded Leopard

Has canines that can be two inches long!

A Cobras
Cobras

Several medicines have been created using cobra venom.

A Cockatoo
Cockatoo

Highly social, smart, and chatty bird.

A Codfish
Codfish

They eat other fish

A Coelacanth
Coelacanth

The coelacanth first evolved almost 400 million years ago.

A Conure
Conure

They are intelligent and noisy, often mimicking sounds and learning vocabulary.

A Coral Snake
Coral Snake

There are over 80 species of coral snake worldwide.

A Crested Gecko
Crested Gecko

The crested gecko can walk on glass and even has a prehensile tail.

A Crested Penguin
Crested Penguin

Has long yellow eyebrows!

A Cricket
Cricket

Male crickets can produce sounds by rubbing their wings together

A Crocodylomorph
Crocodylomorph

Crocodylomorphs include extinct ancient species as well as 26 living species today.

A Cubera Snapper
Cubera Snapper

While very intimidating, the cubera snapper also falls prey to other marine animals like barracudas, whale sharks, and moray eels.

A Darwin’s Frog
Darwin’s Frog

Camouflages itself as a dead leaf!

A Desert Rain Frog
Desert Rain Frog

The desert rain frog doesn't hop

A Dwarf Boa
Dwarf Boa

Some species can change color from dark to light, and back again.

A Dwarf Crocodile
Dwarf Crocodile

Digs burrows in river banks to rest!

A Eagle Ray
Eagle Ray

Majestic underwater bird like fish

A Eastern Barred Bandicoot
Eastern Barred Bandicoot

Digs funnel-shaped holes in search of insects

A Eastern Box Turtle
Eastern Box Turtle

When injured or damaged, the shell of the eastern box turtle can regenerate

A Evening Grosbeak
Evening Grosbeak

They are friendly and non-aggressive to those in their species.

A Finch
Finch

Finches have strong, conical bills that help them break open tough seeds that many other birds cannot.

A Fritillary Butterfly
Fritillary Butterfly

Some emit noxious defense chemicals

A Gaboon Viper
Gaboon Viper

Gaboon vipers are the largest vipers in Africa.

A Galapagos Tortoise
Galapagos Tortoise

The biggest species of tortoise in the world!

A Giant Armadillo
Giant Armadillo

Armadillos have a smell that’s described as strong, sweet and acrid.

A Giant Clam
Giant Clam

Can reach nearly 4ft in length!

A Giant Panda Bear
Giant Panda Bear

Bamboo makes up 99 per cent of their diet!

A Golden Masked Owl
Golden Masked Owl

While flying high above this owl can hear a mouse moving in the tall grass of field!

A Goonch Catfish
Goonch Catfish

The goonch catfish, or giant devil catfish, is one of the most fierce freshwater fish.

A Gopher Tortoise
Gopher Tortoise

It is the only species of tortoise native to Florida.

A Goral
Goral

A mix between a goat and an antelope

A Great White Shark
Great White Shark

Can grow to more than 8 meters long!

A Greenland Shark
Greenland Shark

This shark has the longest lifespan of any vertebrate.

A Haddock
Haddock

The haddock is very popular in both recreational and commercial fishing

A Herring
Herring

People enjoy the taste of the oily fish in many different ways including pickled, smoked, salted, dried and fermented.

A Hippopotamus
Hippopotamus

Has pink anti-bacterial sweat!

A Hooded Seal
Hooded Seal

Hooded seal pups are called bluebacks because the color of the fur on their back is blue-gray. This pretty color made people want to make fur coats out of them and made them a target for hunters.

A Hornbill
Hornbill

The bird has a massive horn on its bill!

A Horned Grebe
Horned Grebe

Sleep with one foot tucked up under the wing so they lean to the side

A Humboldt Penguin
Humboldt Penguin

Found on the South American coast!

A Hyacinth Macaw
Hyacinth Macaw

The Hyacinth Macaw is the largest flying parrot in the world!

A Ibex
Ibex

Can jump over 6 feet straight up from a standstill

A Indian Star Tortoise
Indian Star Tortoise

Popular in the exotic pet trade!

A Jamaican Boa
Jamaican Boa

When a Jamaican boa is coiled up, it almost looks like two snakes together because of color pattern.

A Jumping Spider
Jumping Spider

Some can jump 50 times the length of their bodies

A King Cobra
King Cobra

They are the longest venomous snake in the world.

A Kodkod
Kodkod

The kodkod is among the smallest species of cats in the entire world

A Komodo Dragon
Komodo Dragon

Only found on five Indonesian islands

A Kowari
Kowari

Kowaris do not drink or take water; all they get is the water content in their diet.

A Leatherback Sea Turtle
Leatherback Sea Turtle

They are the largest living turtle and the only sea turtle without a hard shell!

A Lion
Lion

Lives in small groups called prides!

A Malayan Civet
Malayan Civet

Also known as the Oriental Civet!

A Manta Ray
Manta Ray

Can grow up to 9m wide!

A Mantella Frog
Mantella Frog

Some of the smallest and most brightly colored frogs in the world

A Marine Iguana
Marine Iguana

Adult marine iguanas vary in size depending on the size of the island where they live.

A Mola mola (Ocean Sunfish)
Mola mola (Ocean Sunfish)

The ocean sunfish is the biggest bony fish in the world

A Northern Fur Seal
Northern Fur Seal

Dense underfur means they don’t need blubber to stay warm

A Oenpelli python
Oenpelli python

Oenpelli pythons are unusually thin for a python.

A Orange Roughy 
Orange Roughy 

One of the oldest commercially harvested fish

A Oregon Spotted Frog
Oregon Spotted Frog

Oregon spotted frogs are the most endangered frogs in Canada!

A Ovenbird
Ovenbird

The ovenbird is named for its unusual nest, which is shaped like an oven!

A Paddlefish
Paddlefish

Paddlefish have existed since the Cretaceous Period

A Parrotfish
Parrotfish

The parrotfish can change from female to male at some point in its life.

A Peacock Spider
Peacock Spider

They can jump up to 10 centimeters (40 times their body size) and see the full rainbow spectrum of light, including UV.

A Polar Bear
Polar Bear

Could be extinct within the next 30 years!

A Porbeagle Shark
Porbeagle Shark

The porbeagle is one of the few sharks that jumps out of the water

A Potoroo
Potoroo

They can carry items with their tail.

A Python
Python

Female pythons lay eggs and defend them until they hatch.

A Quokka
Quokka

Makes runways through the long grasses!

A Reef Shark
Reef Shark

Grey reef sharks can give birth without males

A Rhino Viper
Rhino Viper

The river jack snake has a gigantic horn-like scale on the tip of its nose.

A Royal Penguin
Royal Penguin

Can reach speeds of 20mph!

A Russian Tortoise
Russian Tortoise

Known by at least five different names

A Sailfish
Sailfish

Fast billfish with a sail-like dorsal fin

A Sambar
Sambar

Male sambars will compete for mates by clashing together with their antlers

A Sand Tiger Shark
Sand Tiger Shark

The sand tiger is the shark most commonly seen in aquariums.

A Sandpiper
Sandpiper

Some sandpipers can migrate more than 8,000 miles without stopping!

A Sarus Crane
Sarus Crane

Parents use low calls to tell their chicks to freeze and lie still when danger lurks.

A Shoebill Stork
Shoebill Stork

Adults greet each other by clattering their bills together.

A Silky Shark
Silky Shark

Has an extremely acute sense of hearing

A Smooth Hammerhead Shark
Smooth Hammerhead Shark

Congregate in large groups during annual migrations

A Snow Leopard
Snow Leopard

Unlike other big cats, snow leopards don’t roar.

A Snowy Owl
Snowy Owl

One of the largest owl species in the world!

A Southern Hognose Snake
Southern Hognose Snake

The southern hognose snake has an upturned snout that enables it to dig through the soil.

A Sperm Whale
Sperm Whale

Each tooth weighs 1kg!

A Spinner Shark
Spinner Shark

Can have up to 20 babies

A Spiny Dogfish
Spiny Dogfish

Found in ocean waters worldwide!

A Sulcata Tortoise
Sulcata Tortoise

Some cultures in Africa believe the sulcata tortoise is an intermediary between the people and their ancestors and gods.

A Sun Bear
Sun Bear

The smallest species of bear in the world!

A Syrian Hamster
Syrian Hamster

Can get used to and respond to human voice

A Tailless Whip Scorpion
Tailless Whip Scorpion

The average lifespan of these strange creatures is 5 to 10 years; however, tailless whip scorpions have been known to live up to a whopping 15 years in captivity!

A Takin
Takin

The takin can leap some 6 feet through the air

A Tamarin
Tamarin

These tiny yet intelligent monkeys often give birth to fraternal twins.

A Tarpon
Tarpon

Its genus dates back to the Cretaceous period – 113 million years ago

A Teddy Bear Hamster
Teddy Bear Hamster

The oldest recorded teddy bear hamster was six and a half.

A Timor python
Timor python

Ironically, Timor pythons have never been found on the island of Timor.

A Tree Kangaroo
Tree Kangaroo

It’s the only macropod that lives in trees.

A Turtles
Turtles

Some species of aquatic turtles can get up to 70 percent of their oxygen through their butt.

A Uakari
Uakari

Have a very short tail for their size!

A Umbrellabird
Umbrellabird

Migrates up and down the mountains!

A Urial
Urial

Urials are the ancestors of modern-day domesticated sheep.

A Uromastyx (Spiny-Tailed Lizard)
Uromastyx (Spiny-Tailed Lizard)

Spiny-tailed lizards "sneeze" out salt!

A Viper
Viper

Vipers are one of the most widespread groups of snakes and inhabit most

A Wandering Albatross
Wandering Albatross

Featured in “The Rime of the Ancient Mariner”

A White Shark
White Shark

White Sharks live in all of the world's oceans.

A White Sturgeon 
White Sturgeon 

They don't have any teeth!

A Xingu River Ray
Xingu River Ray

The Xingu River ray is only found in the Xingu River in Brazil.

Vulnerable Species List

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