We strongly encourage catch and release to help sustain the fish population in Cabo San Lucas. However you are entitled to keep the fish you catch according to limits established by the Mexican government. Please discuss your plans on keeping or releasing your catch with the captain before your trip, so that they may follow proper procedures. If you're not planning on eating it, please release it.
If you catch a nice marlin or billfish, the crew can bring it on board for a quick picture then let it swim another day.