One-woman mission to protect hammerhead shark

Swimming off Cocos Island in the Pacific Ocean, Ilena Zanella had her first close encounter with hammerhead sharks.

As social creatures, the sharks gather in their hundreds, and soon she found herself surrounded, according to BBC News.

Easily spooked by the bubbles coming from her diving equipment, the sharks appeared shy, vulnerable and beautiful.

"I saw the vulnerability of this endangered species," she says.

"This experience changed my life and I decided to dedicate my work and myself to the protection of hammerheads."

Hammerhead sharks are something of a curiosity in the animal kingdom, with their elongated heads and pinprick eyes.

Of the nine known species, several are endangered, including the scalloped hammerhead, which is found off the Pacific coast of Costa Rica.