The Fishing Rod Situation
You pick up the fishing rod from the pond just outside the lake near the Gerudo Valley entrance. There is an old man there who gives it to you if you've already spoken to him once. He doesn't ask for rupees. The fairy at that pond can also fill your empty bottles if you've defeated someone who drops a fairy. Just don't expect the fish to behave predictably the first time you try. Walk to any body of water where fish spawn — Lon Lon River, Lake Hylia, the river behind the forest guard's house near Lost Woods. Stand at the edge and press A to cast. A timing bar appears on screen. It drains downward from the top. When the indicator hits the green zone, press A again. That sends the line out. The fish will appear underwater. You see them swim around. Now the bar starts draining again in a different pattern. Wait for it to reach green and press A to reel in. The fish fights back by making the bar behave erratically. Some species make it jump around more than others. Keep timing your presses to the green zone until the bar fully retracts and you've caught it. I spent probably two hours on my first attempt at Lake Hylia because I kept pressing A too early and spooked the fish. The bar doesn't reset when you miss. You just lose the current fish and have to recast. It feels frustrating at first but the rhythm clicks after you do it a dozen times without thinking about it.
Ocarina Of Time Fishing Guide
This is basically everything you need. The core loop never changes between locations. The only variable is how aggressively the bar moves during the reel-in phase depending on which fish you are targeting. The fish in Lon Lon River are mostly small ones — bluegill and bass types. They are slower and easier to catch. Good for learning the timing. The lake has bigger fish that require quicker reactions. You can actually find a certain key fish you need to complete a side quest involving the fisherman near the lake. He wants a specific fish type and if you bring it to him he gives you a song or item depending on which version you are playing. The river near the forest guard house has a particular fish you need for the fishing minigame inside the Hyrule Castle town pub on the GameCube version. That minigame is separate from the open-world fishing and uses its own timing system. Don't confuse the two. They share the same button but behave differently. The castle minigame gives you limited casts and a point system. Open world fishing is unlimited and you just keep going until you have what you need.
Edge Case: The Fast Fish in Lake Hylia
There is one species in Lake Hylia that moves significantly faster than the rest and changes direction mid-bar. I nearly threw the controller when I realized I was wasting casts because I had never seen it move like that. The workaround is to let the bar drain almost all the way down before pressing. Waiting longer gives you more reaction time once the fish jerks. You lose a bit of margin but it is better than spamming A and immediately losing the fish. Caught fish sell for rupees at any shop. The prices are not great. You will not get rich from fishing. It is more useful for quest requirements and the occasional side quest reward. The GameCube port added a dedicated fishing minigame with better rewards but that is a completely separate thing from the original N64 experience. If you are playing the Master Quest version nothing changes. Fishing works identically.
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Common Mistakes Beginners Make
Pressing A the moment the bar starts moving. It does not work like that. The bar has to reach the green zone on its own before you press. Spamming A just wastes your cast and scares the fish away. Also standing too far from the water's edge. If you cast from too far back the line doesn't reach the fish zone and you waste time walking back. Stand right at the water and you are fine. Fishing is not a major plot requirement in Ocarina of Time. You do not need to catch anything to progress the main story. It exists as filler content and side quest material. If you are impatient you can skip it entirely without missing anything critical. But if you want the full experience it takes about twenty minutes to learn and another twenty to reliably catch the quest fish you need.