Contrary to the emerging conventional wisdom, younger users aren't abandoning Facebook, the company's chief financial officer said today — they're just using rival social services more than ever before. Answering a question on Facebook's Q1 2013 earnings call, David Ebersman dismissed the suggestions that users aged 15 to 25 are spending less time on the service.

"I'd start by saying we remain really pleased with the high level of engagement by people of all ages all around the world," he said. "We continue to have really high penetration rates among that age group both in the US and globally. And younger users remain among the most active and engaged users that we have on Facebook."

The competition is growing

At the same time, surveys have indicated that teens are spending an increasing amount of time using services not owned by Facebook — primarily Tumblr, but also SnapChat.

"We take this feedback seriously," Ebersman said. "But our sense is that much of the concern stems from the assumption that this is a zero-sum game, and that's not how we see it." And at least one of the apps growing in popularity with teens happens to be one Facebook owns. Instagram is very popular with teens, Ebersman said, and the company said today that the photo-sharing community had grown to 100 million active users.

Ebersman sidestepped the question of whether teens are spending less time on the platform than they used to, but said the company's position is strong. Despite the increased competition, Facebook sees the rising tide of social apps lifting all ships — Facebook included.

"We think the overall amount of time spent on services that enable you to connect and share is growing, and will continue to grow, because these kind of services are really engaging and good," Ebersman said. "It's great for us to be the leader in a market that's expanding rapidly, with the foundation we have with both Facebook and Instagram." Facebook's recent push on Messenger, which included the release of Chat Heads and Stickers, represent another step in that direction.

Nevertheless, Ebersman made it clear that the threat of so-called "Facebook fatigue" would require constant attention. "The challenge for us is to continue building great products that appeal to users of all ages," Ebersman said.