Tiger triplets turn 1

The Calgary Zoocelebrated the first birthday of three Amur tiger triplets Saturday.

Kira, Samkha and Vasili were born one year ago Saturday after their mother's last two attempts at motherhood were unsuccessful.

Amur tigers are classified as endangered and there are only about 350 of them left in the wild today.

These cubs represent about one per cent of the world population.

The births were a result of a breeding program the Calgary Zoo participates in.

When born, the cubs weighed about 750 grams each and stayed in the den with their mother for roughly three months before venturing into public view.