Canadian-born London zookeeper Grant Kother stripped naked in a bid to encourage people to take part in 'Streak For Tigers' - a naked run inside London Zoo - taking place on 15 August.
The run is taking place to raise money to save the drastically reducing number of Sumatran tigers. A pack of tigers is called a streak, which inspired the clever name for the fun run.
Kother posed the photographs, with only a bucket to protect himself from the chill of the May air. It's hoped that his shots will encourage fundraisers to join him and enable the Zoological Society charity to continue its vital conservation work.
Lucy Osman, Challenge Events Manager said, 'We're thrilled to be holding such a daring and unusual event after hours at ZSL London Zoo.'
'We're hoping that by taking on this outrageous challenge, streakers' friends and families will dig deep to show their support and help protect tigers around the world.'
There are around 300 Sumatran tigers present in the world today. 300 runners are being encouraged to join in the festivities - one to represent each of the tigers whose lives could be preserved.
If you would like to participate in Streak For Tigers you can find out more information at the Zooilogical Society of London website.