Blue Peter presenter Helen Skelton is to bow out after five and a half years next month - and will be replaced by CBBC colleague Radzi Chinyanganya.
It means another big change for viewers who learned the identity of another new host, Lindsey Russell, only a fortnight ago after she won a talent hunt to land a position on the show.
Daredevil Skelton, who has set world records during her stint on the long-running series including a kayak journey down the Amazon, was recently announced as a new presenter for BT Sport.
Chinyanganya will join the show in mid-October to become the programme's 33rd presenter, joining Russell and and regular host Barney Harwood, who also graduated to the show after becoming a familiar face on CBBC.
Chinyanganya has been a reporter for Match Of The Day Kickabout and is a presenter of Saturday morning show Wild. He is 26 and comes from Wolverhampton.
CBBC controller Cheryl Taylor said he had already become a "firm favourite" with viewers of natural history show Wild.
He said: "When I was younger all I ever wanted to be was a Blue Peter presenter. Blue Peter was my absolute favourite show - in fact, 16 years ago I earned my very own Blue Peter badge, which I still have, and now very soon I will be starting my ultimate dream job of Blue Peter presenter. Unbelievable.
"It's impossible to put into words what this means to me, but I just cannot wait to see what adventures and challenges I will be up to. It's going to be great to work with Barney and Lindsey."
Skelton said: "I have been so lucky over the last five years. I have travelled the world, met amazing people, been part of some unbelievable adventures and I have loved every second of it.
"However, Blue Peter is a 24 hours a day, 365 days a year job, and with so many exciting new projects in the pipeline, I can't be there as much as I would like, so I've made the difficult decision to hang up my badge.
Programme editor Ewan Vinnicombe said: "Helen has been a fabulous Blue Peter presenter and will be missed by both our audience and the whole team here. I'd like to thank her for all of her hard work and commitment to the show and know that she'll remain a friend of the programme in the years to come. "
Blue Peter moved from BBC1 to digital channel CBBC last year.