The number of teenagers that update a weblog has fallen by half since 2006, says the Pew Internet and American Life Project.
Research by the US organisation says that just 14 percent of 12-to-17 year olds blog, with the majority preferring to "micro-blog" or make shorter postings to social networks such as Twitter and Facebook.
However, the study did reveal that the number of over 30s blogging had risen from 7 percent in 2007 to 11 percent in 2009.
Senior researcher for Pew, Amanda Lenhart, told the Associated Press micro-blogging had "kind of sucked the life out of long-form blogging", although she said it was unlikely to disappear completely.
Pew also said that nearly a third of teens and 55 percent of 18 to 29 year olds use their mobile phone to access the web.
See also: 75% of teens can't live without the web
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