CAPE TOWN, SOUTH AFRICA (REUTERS) - A six-year study concludes that South Africa's great white sharks could die out due to human interference, ocean pollution and a limited gene pool.

Experts say years of poaching, overfishing and pollution have left the sea predator's numbers in decline, with only 350 to 520 sharks left.

"The causes of decline can also be an historical situation, where the animals have been killed for so long and so extensively that the population never recovered," said marine biologist Sara Andreotti.

South Africa is the first country to protect the great white shark, and such news will likely come as a blow.