Northern pikes are a type of fish.
Like all types of fish, each northern pike gives one fish fillet when caught.
Catching northern pikes
Northern pikes can be caught with green and gold lures in any fishing spot, but their favorite spot is #8 (the rocky area near the fishing boat).
Northern pikes can be caught in large circles and therefore are easier to catch.
See Fishing List for more detailed information.
Northern pikes in the fishing book
The northern pike is on page 9 of the fishing book:
Always on the tail of other fish! They'd appreciate it if you took the pike for a breather.