The gumblejack was a type of fish that was considered to be one of the tastiest in Mutter's Spiral. The Doctor liked to fish for them, specifically once in his sixth regeneration. (TV: The Two Doctors)
Frobisher hunted for some gumblejack he had created in the Doctor's TARDIS. They made high-pitched squeaking noises. (AUDIO: The Holy Terror)
The Doctor wrote a book about the history of gumblejack fishing in the eighth galaxy. It became a bestseller. (PROSE: Spiral Scratch)
The TARDIS had a tiny fish pond in the control room which was full of rainbow gumblejacks. (PROSE: The Novel of the Film)
The Eighth Doctor once planned to eat some dry-roasted gumblejack fritters and re-read The Final Problem. (PROSE: The Bodysnatchers)