Fishing was the act of catching fish. A sport was developed around it.
The Second Doctor, with Jamie McCrimmon and Victoria Waterfield, accompanied William Wallace on a fishing trip in 13th century Scotland. Unlike the others, the Doctor threw the fish back into the river after catching them, as he believed in "catch and release." English soldiers led by Captain John Fitzroy attempted to arrest them for poaching but Wallace killed Fitzroy in defence of his companions. (PROSE: On a Pedestal)
The Fourth Doctor stated he once caught a huge salmon in the River Fleet. He shared it with the Venerable Bede. (TV: The Talons of Weng-Chiang) The Doctor went fishing on Tara; he complained when he caught nothing. He kept a fishing rod in the TARDIS. Romana I did not know what fishing was. (TV: The Androids of Tara)
The Sixth Doctor was fond of fishing for Gumblejack; he considered them amongst the tastiest fish in Mutter's Spiral. (TV: The Two Doctors) One of the Doctor's fishing trips was interrupted by his seventh incarnation, who was searching for a segment of the Key to Time. (COMIC: Time & Time Again) The Doctor decided to go fishing on Világ, but the fish were startled by Corporal Reid. (AUDIO: Arrangements for War) The Doctor gave up fishing when he started thinking that it wasn't fair on the fish. (AUDIO: The Wormery) He later went fishing on Majus Four, but was summoned to Brighton in 1989 by Bob Lines. (PROSE: Business Unusual)
The Seventh Doctor once tried to relax by fishing on the planet Adeki, but the attempt was frustrating enough that he ended up angrily snapping his fishing rod over his knee. (COMIC: Planet of the Dead)
James Blake went fishing at Mill Creek on first of December, 1955, the day he was due to drive the bus that Rosa Parks would famously be arrested on, because Krasko changed his schedule in an attempt to alter history. Graham O'Brien and Ryan Sinclair joined him and warned him of an alleged black protest, he left fishing to work as a bus driver that evening. (TV: Rosa)