Tuna

The tuna is a fish you catch off the pier. Look for a huge shadow. In the northern hemisphere look for it in Nov – Apr, at any time of day. It can only appear after you have caught 50 fish. Nook's Cranny pays 7,000 Bells, C.J. pays 10,500 Bells.

Fish from your pier for an XX-Large shadow, after 50 catches. It sells for 7,000 Bells, and throwing fish bait off the pier helps bring more big shadows in.