How much of our biodiversity is at risk?

Another global summit - COP15 – has concluded in Canada. It focused on biodiversity, which is the variety of all living things on earth. Activists, charities and ministers came together hoping to find solutions to protect and save forests, wetlands and water bodies before it’s too late. Recent studies have suggested that nearly a third of all species are currently endangered due to human activities such as logging, climate change and farming. And scientists are warning that the biodiversity clock is ticking in Africa and around the world, putting human life and wildlife at risk. So how bad is the situation and what needs to be done to protect biodiversity? Alan Kasujja speaks to the BBC World Service Environment correspondent, Navin Singh Khadka.