18 Pound Salmon

A 18 Pound Salmon is a trophy fish that can be caught while fishing. It does nothing, but can be equipped in the off-hand and shown off.

If you merely wield the trophy fish, it will not show on your character. You have to type 'z' to force the wielded items to display.

Source
This item can be fished in:
 * Alterac Valley
 * Burning Steppes
 * Deadwind Pass
 * Eastern Plaguelands
 * Feralas (Jademir Lake only)
 * Scholomance
 * Silithus
 * Stratholme
 * Western Plaguelands
 * Winterspring
 * Zul'Gurub