A new survey has found that the population numbers of great white sharks (Carcharodon carcharias) off South Africa is about half what had been expected. A paper in Marine Ecology Progress Series shows the results of a six year study into the numbers of the apex predators and shows that there are only between 353 and 522 of the sharks. Of these, around 333 are of breeding age.

The study used dorsal fin imagery, genetic biopsy sampling and microsatellite marking to count the sharks. It suggests that trophy hunting, shark nets and pollution have caused the population to decline and that the South African population of great whites may become extinct soon.

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