How solving the mystery of pregnant tiger sharks in the Maldives could help save the apex predator

Millions of sharks are killed every year, but a population in the island paradise could hold clues to where they breed and give birth, enabling better protections

Within minutes the sharks, with their characteristic stripes and sharp, jagged teeth, appear from the depths of the Indian Ocean. They follow the scent of fish blood and oil coming from tuna heads a research team has hidden under a pile of rocks in a shallow sandy area.

The tiger sharks, perhaps eight or nine and up to four metres long, circle the divers, at times only an arm's length away. All are females, two with bite marks on their flanks and fins, indicating recent mating. Some have remarkably fat bellies.

Tiger sharks circle at the Tiger Zoo dive site