Research estimates there are fewer than 4,000 of the big cats left in the wild. A century ago there were around 80,000.
The crisis is blamed on poachers and trophy hunters. Economic development is also a major factor in their decline because it ruins their habitat.
Campaigner Martin Hughes-Games has been studying the tiger count in India, which accounts for 60% of those left.
He said: “India is a country that’s industrialising incredibly fast. There are roads and railway lines and industries everywhere you look.