Total count list:
At the title screen, press Up, Up, Down, Down, L1, R1, L1, R1, X, Circle, Start. Then, press Select at the options screen.

Big fish:
At the lure selection screen, press Triangle + Circle + Square + X + R1 + R2 at the same time.

Unlock Concave Dam:
Play the game 50 times.

Unlock Lake Center:
Play the game 100 time.

Attract Fish:
At the title screen, press triangle, X, O, Square, Up, Down, Left, Right then just fish and catch all the fish you want.