Facebook is rapidly losing ground against rival Internet platforms in attracting and keeping US teenagers, a survey showed.
The Pew Research Centre report confirms a trend seen in other surveys, showing a sharp drop in Facebook's share of what had long been a core age segment for the huge social network.
The survey found 51% of US teens ages 13 to 17 use Facebook, compared with 85% for YouTube, 72% for Instagram and 69% who are on Snapchat.
The landscape has shifted since a 2014-15 Pew survey which found Facebook leading other social networks with 71% of the teen segment.
“The social media environment among teens is quite different from what it was just three years ago,” said Pew researcher Monica Anderson, the lead author of the report.
“Back then, teens' social media use mostly revolved around Facebook. Today, their habits revolve less around a single platform. At the same time we've seen this shift, teens are more digitally connected than ever.”
The survey showed a split over the impact of social media on the lives of the teens.
Pew found 31% said social media has had a mostly positive impact, with 24% describing its effect as mostly negative. The remaining 45% said it was neither.
Those who reported a positive impact cited the ability to stay connected, find news and people with similar interests.
Others who found social media harmful cited the potential for online bullying, spreading of false information and addiction.
Facebook is the world's biggest social network with some two billion regular users.
But some surveys and analysts suggest it is losing appeal to younger users amid a rise in services like Snapchat and Facebook-owned Instagram.
A report earlier this year by the research firm eMarketer said Snapchat is drawing youths away from Facebook at a quicker clip than Facebook-owned Instagram.
According to eMarketer, Facebook will lose two million US users under the age 24 this year, offsetting those losses with gains among older users.
A report last year by investment firm Piper Jaffray showed Snapchat is the preferred social network for US teens, with 47% using the platform.