Inbreeding of tigers must be a factor in its survival in the wild. I read that a minimum breeding population of 500 is needed for long term viability (i.e. per grouping). There are only around 1,411 left in the wild in India, broken up into small groups on reserves. The Siberian tiger also has an inbreeding problem. If enough forest land between the parks are eventually restored then tigers can move around freely reducing the risk of inbreeding. Tigers are so rare that some males can go an entire lifetime without finding a female to mate with. Sad i know but true.