Some animals are not born hot-tempered, but a decade of life without a spouse might have been enough to turn a gibbon cranky. Seeing other animal couples living happily together, the lonely animals tend to become impatient, restless and even violent.

The major reason for their difficulty in mating lies in the fact that they are rare and precious.

If an elephant wants to go on a journey to mate, it is impossible to find a cage and truck big enough to transport it. Importing potential mates from foreign countries has proved impractical due to customs procedures and paperwork.

According to regional newspapers, about 5,000 endangered animals in about 400 species across the country are living single lives.