Spear fishing for fish ?

That may be true where you live, but you should check your local and state (country) regulations. Here in Alabama, you can legal bow fish but not for game-fish. (IE B, Crappie, Catfish) as for other fish like Gar and Carp, you can use a bow and arrow to harvest. You can also use a spear gun for saltwater fish. But as for using an Air rifle, that is illegal.