When playing Stardew Valley, you'll come across a request for Walleye for Sebastian's Book Club. Unfortunately, Walleye is one of the harder fishes to catch because it requires preset circumstances or a high crafting level.
Where can I find a Walleye fish in Stardew Valley?
The first requirement is that the day must be rainy, and since the weather is pretty random, that is difficult. The only way to guarantee it is to use Rain Totem, which can be found in Skull Cave or crafted if you have reached Foraging Level 9. Additionally, it must be the Winter or Fall season for them to appear.
Related: How to catch Chub in Stardew Valley
The above map shows red circles over the fishing spots you should pay attention to. Go to any of those spots when the conditions above are met to get a Walleye in Stardew Valley. In reality, it's pretty easy to find this fish if the conditions above are met. When it rains in Winter or Fall, you will catch at least one Walleye.
A Rain Totem will never work on a festival day because those days have preset weather conditions which are normally sunny. Make sure you don't try to get this fish on a festival day because it won't happen.