Estimating Shark Mortality: Challenges and Insights

Hollywood has given sharks a terrible reputation. But in reality, the finned fish should be far more scared of us, than we of them.

Millions of sharks are killed in fishing nets and lines every year.

One statistical claim seems to sum up the scale of this slaughter – that 100 million sharks are killed every year, or roughly 11,000 per hour.

But how was this figure calculated, and what exactly does it mean?

We go straight to the source and speak to the researcher who worked it out, Dr Boris Worm, a professor in marine conservation at Dalhousie University in Canada.

Presenter: Lizzy McNeill Producer: Nicholas Barrett Series producer: Tom Colls Production coordinator: Brenda Brown Sound mix: Annie Gardiner Editor: Richard Vadon