UK charities are raising awareness of the hedgehog population decline by encouraging everyone to check their bonfire carefully before lighting them.

Hedgehogs are in decline across the UK with the London Wildlife Trust reporting numbers falling to less than one million from 30 million in the middle of the 20th century.

Some experts believe if the current decline continues the hedgehog could eventually become extinct.

The video below captures friends Sophie Barker and Rob Davis using the integrated thermal imaging camera in the Cat® S60 smartphone to help locate the animals. The thermal camera highlights temperature contrasts to reveal hedgehogs as small red and orange balls of heat, hidden amongst the cooler wood, which shows up in purples and blues on the screen.

For further information on the plight of hedgehogs and how to keep them safe around bonfire time, get advice from The Wildlife Trust.

Film by Tom Sands, Producer and Director at Substantial Films.