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Endangered animals: Creatures that have come back from the brink of extinction

Thousands of critically endangered snails have been released back into the wild on Bermuda after being rescued from the edge of extinction. But they're not the only animals who have been saved from dying out.
Thousands of critically endangered greater Bermuda land snails have been released back into the wild on Bermuda after being at risk from dying out. It was after a big international conservation effort, including a small number of remaining snails being sent to Chester Zoo in the UK for a breeding programme. It got us thinking about other endangered animal good news stories...
Great Bermuda land snailChester Zoo
Indian rhinos were once common across the northern part of the Indian sub-continent, but by 1975, there were only 600 left. Dedicated conservation saw their numbers increase to 3,000 by 2012.
Indian rhinoChester Zoo
After nearly 30 years of team conservation efforts between different states in the US, the number of grizzly bears in the Greater Yellowstone Ecosystem across Montana, Wyoming and Idaho has grown to around 700 bears - up from 136 counted in 1975.
Grizzly bearReuters
Manatees were listed as "endangered" in 1967, when only a few hundred swam in Florida waters. But in 2016 their status was changed from "endangered" to "threatened" because of improvements in the manatees' habitats. There are now more than 6,300 in Florida and around 13,000 worldwide.
Once native to 23 countries in Asia, tigers can now be found in only 11, and have disappeared entirely from the wild in Cambodia and in Vietnam in recent years. But government initiatives to track tiger populations and stop illegal hunting have showed a promising increase in population numbers: 2,226, up from 1,411 in 2007.
After 10 years of conservation work in Indonesia's Sebangau National Park - which holds the largest wild orangutan population in the world - researchers found numbers had risen by 7 percent since 2007, with 5,826 orangutans recently counted. However most of the world's orangutans live outside of protected areas and are still threatened by logging and farming.
During the 1980s researchers in Florida monitored green sea turtles as they built their nests, counting fewer than 50 nests per year during the nesting season. After a lot of work to protect their environment, in September 2015, researchers reported counting 12,026 nests, up from 11,839 nests set in 2013.
Green sea turtle