What do ripples on the water indicate?

The bubbles you occasionally see indicate a higher activity of fish in that tile. If you successfully land your lure within or close to that bubbling tile when fishing, you will get a visual confirmation with the water splashing. The area for the benefit slightly extends outside of the tile, and the different visual effects can be seen below:

Note: The Standard Fishing Visual Effect is also displayed when the bobber hits the water.

When fishing from the ripples, you will notice that fish and other debris bite much quicker. With lures and bait, you will find fish biting within the first 5 seconds of fishing.