In order to obtain this Trophy you must raise Noctis' fishing level at least once.
When you first reach Golden Quay there is a pier opposite from the parking spaces. Going to the end of this pier you will discover that Noctis can cast a line and begin fishing. Baits and different types of durable fishing line can be purchased from the vendor also on the pier.
After catching between 2-4 fish Noctis' fishing level should increase. Once you make camp or sleep for the night and Fishing goes up to level 2 you will unlock this Trophy.