Mountain Gorilla, Rwanda. About 880 mountain gorillas, who have thicker and more fur than other great apes, live in forests high in the mountains in the Congo Basin. They are threatened by civil conflict, poaching, and an encroaching human population.Panoramic Images/Getty Images
Long-tailed pangolin, Manis tetradactyla, Congo, DRC, Democratic Republic of the Congo
Captive Yangtze Finless Porpoise Gives Birth To Second Cub In Wuhan
Javan Rhinoceros (Rhinoceros sondaicus) forages in understory, Ujung Kulon National Park, Indonesia
Sumatran Orangutan (Pongo abelii) twenty-six year old male, named Halik, reaching out, Gunung Leuser National Park, Sumatra, Indonesia
black rhinoceros
Sumatran tiger adult
Indonesia, Sumatra, Gunung Leuser National Park, Sumatran elephants (Elephas maximus sumatranus) bathing in a waterhole
First Vu Quang Ox or Pseudoryx nghetinhensis ever captured eats leaves in a cage outside Hanoi
Leatherback sea turtle, Dermochelys coriacea, Galibi National Reserve, Surinam
Sumatran Rhinoceros (Dicerorhinus sumatrensis) female, Sumatran Rhino Sanctuary, Way Kambas National Park, Sumatra, Indonesia
Amur Leopard
AF07 ALA0114.jpg
Hawksbill turtle
Endangered Chinese Tigers Find New Home
Western lowland gorilla juvenile male feeding
Mountain Gorilla, Rwanda. About 880 mountain gorillas, who have thicker and more fur than other great apes, live in fo

Panoramic Images/Getty Images
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See 17 Animals on the Verge of Going Extinct

May 20, 2016

More than 10,000 species—everything from the Asian Elephant to the Bluefin tuna—have earned a place on the list of endangered animals, according to the International Union for Conservation of Nature.

But a select group of endangered species face an even greater threat. Animals in this group, included in the galley above, have been labelled "critically endangered" and teeter on the brink of extinction.

The threats faced include everything from deforestation to climate change. And, conservationists say, any effort to save endangered animals must deal with the surrounding issues to sustain itself. The annual Endangered Species Day—recognized on May 20—is a great place to start.

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