The number of endangered species continues to climb at an alarming rate. Drawing attention to their plight is paramount to providing opportunities for recovery. According to the World Conservation Union (IUCN), over 18,000 species are known to be critically endangered, endangered or vulnerable. The list of the top ten most endangered has been compiled by consulting the IUCN Red List of Threatened Species, the World Wildlife Fund and other organizations focused on this cause. Once selected, the species were ranked according to their surviving populations, from lowest to highest.

The ivory-billed woodpecker once flourished in the southeastern United States and parts of Cuba. However, it has now become so endangered that many scientists believe it may be extinct. Threats include hunting and habitat loss due to logging and development.

The Baiji, or Chinese river dolphin, has been downgraded to the IUCN’s possibly extinct status. This freshwater dolphin once flourished in China’s Yangtze River. However, pollution and habitat loss due to human development have pushed this species to the brink of extinction.

The Amur leopard is the rarest of all large cats, with only 40 known to still exist. They call the Primorye region of Russia’s Far East home. These leopards face numerous threats, including illegal hunting, global climate change and loss of habitat due to logging, road construction and development.

The Javan rhinoceros once flourished in the swamps of Asia. However, there are now less than 60 of these rhinos in existence, making them the most endangered rhinoceros in the world. The rhino was hunted to near extinction for its horn and scientists are unsure as to whether the current population is large enough to prevent its extinction.

The greater bamboo lemur lives in the forests of the Island of Madagascar. Currently, there are less than 100 surviving members of this species. They continue to face a shrinking habitat, the result of logging and the burning of forest for agricultural development.

The northern right whale was hunted to near extinction for its oil-rich blubber. Only around 350 of these whales remain in the North Atlantic, and they currently face the threat of entanglement in commercial fishing nets.

The world’s biggest cat, the Siberian tiger, has dwindled to a population of around 500. Surviving in the birch forests of Russia’s Far East, they face threats from poaching and habitat loss due to logging and development.

There are fewer than 700 mountain gorillas still surviving in the highlands of east-central Africa. The gorillas are threatened by continuous wars and poverty, driving illegal hunting and logging.

The Hawaiian monk seal lives on the remote beaches of the Hawaiian Islands. Their population has declined sharply to less than 1000. Scientists are unsure of the exact cause, believing it may involve sea changes, competition with commercial fishing and net entanglements.

The population of leatherback sea turtles, the world’s largest turtle, has declined as much as 78 percent since 1982. These turtles face numerous threats, including theft of their eggs by humans and coastal development.