a burrowing, snake-like creature who performs stenography for newspapers, magazines, or news websites or prepares news to be broadcast, spending much of its time stuck inside the anus of its superior.
The media is full of gerbilists - they spent so much time up Murdoch's ass that their view is permanently stained.
A lowly form of journalism; grubby and/or focussing on the minute and irrelevant. Often happens at the expense of reporting issues in the public interest.