Two reasons why Siberian Tigers endangered?

Overhunting was an early reason for the decline of this species, Indian princes and foreign hunters took an enormous toll of the great cats in the 1800's to mid 1900's.

As the human population expanded, more land was cleared for settlements and crops, meaning less land for tigers. Conflicts occured, and the tiger was the loser. Finally, quack Chinese medicines made from tiger body parts led to a lucrative poaching trade, pressuring the tigers even more. Today, Bengal tigers are afforded the strictest protection, and the last survey showed an increase in their numbers, up to around 1800 from a low of around 1411.