Some of Wales' most endangered species are "at risk of vanishing" from an area of the country's largest national park, experts have warned.

The National Trust said Nant Ffrancon, a valley in Eryri National Park, was facing "serious ecological decline" with some species in danger of disappearing altogether, including the mountain blackbird and the mountain finch.

Now, a new £1m scheme is aiming to restore and conserve more than 4,000 acres of habitats at Eryri, also known as Snowdonia.