Sir David Attenborough has signed up to Instagram for the first time to help spread his environmental message.
"I am making this move... because, as we all know, the world is in trouble," he said in his first video message on the social media platform.
"Continents are on fire. Glaciers are melting. Coral reefs are dying... The list goes on and on," he continued.
Within an hour of his first post, he had more than 200,000 followers, and by 16:15 BST he had 1.2m followers.
"Saving our planet is now a communications challenge," the veteran broadcaster said.
Tennis player Sir Andy Murray and body coach Joe Wicks were among those to post welcome messages.
View this post on Instagram
David Attenborough has spent a lifetime travelling, exploring the wild places of our planet and documenting the living world in all its variety and wonder. He’s also witnessed the damaged caused. Saving our planet is now a communications challenge. We know what to do, we just need the will. That’s why we want to share this message on Instagram. Because there is hope and together, we can inspire change. Social media isn’t David’s usual habitat so while he’s recorded messages solely for Instagram, like the one in this post, we're helping to run this account. In case you’re wondering, ‘we’ are Jonnie and Colin and we worked with David on A Life On Our Planet. So, as well as sharing the messages he’s recorded especially for this account we’ll also post some exclusive clips and behind the scenes content. Stay tuned.
Sir David said he would use the platform to share videos explaining "what the problems are and how we can deal with them".
Concluding his message, the 94-year-old invited viewers to "join me - or as we used to say in those early days of radio, stay tuned."
Frequent collaborators Jonnie Hughes and Colin Butfield will help manage the account and its various technical aspects.
"Social media isn't David's usual habitat," they wrote in a message accompanying the naturalist's introductory video.
Sir David's Instagram debut precedes the release of latest book and Netflix documentary, both titled A Life On Our Planet.
The film sees him reflect on his career and the decline of the planet's environment and biodiversity he has observed first-hand.
It remains to be seen, though, if he will better the impressive debut Jennifer Aniston made on the platform last October.
The actress attracted almost five million followers in 12 hours after posting a selfie with her fellow Friends cast members.
Earlier this year Dwayne "The Rock" Johnson was named the celebrity thought to be able to charge more than any one else for a sponsored Instagram post.