Copper redhorses are a type of fish.
Like all types of fish, each copper redhorse gives one fish fillet when caught.
Catching copper redhorses
Copper redhorses can be caught with red lures in any fishing spot, but their favorite spot is #1 (the shallow area in front of the fisherman's hut).
Copper redhorses can be caught in large circles and therefore are easier to catch.
See Fishing List for more detailed information.
Copper redhorses in the fishing book
The copper redhorse is on page 2 of the fishing book:
'This friendly, relaxed and long-living fish has found a permanent home in your lake.'