Three of the nine tiger subspecies — the Bali, Javan, and Caspian — already have become extinct in the past 70 years.
Much has been done recently to try to save tigers, but conservation groups say their numbers and habitats have continued to fall, by 40 percent in the past decade alone.
In part, that decline is because conservation efforts have been increasingly diverse and often aimed at improving habitats outside protected areas where tigers can breed, according to a study published in September in the Popular Library of Science Biology journal.
Putin has done much to draw attention to tigers' plight. During a visit to a wildlife preserve in 2008, he shot a female tiger with a tranquilizer gun and helped place a transmitter around her neck as part of a program to track the rare cats.
Later in the year, Putin was given a 2-month-old female Siberian tiger for his birthday. State television showed him at his home gently petting the cub, which was curled up in a wicker basket with a tiger-print cushion. The tiger now lives in a zoo in southern Russia.
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