Minecraft wiki entry for Fishing, associated text: After a period of waiting, a trail of water particles appears a short distance from the bobber and heads toward the bobber (provided that the Particles Video Setting is not set to Minimal). When the particle trail reaches the bobber, the bobber dips below the surface and the player must immediately use the rod again to reel in the line. The window for reeling in when the bobber submerges varies in duration, averaging about half a second. If a bite is missed, the line can simply be recast or left in the water to wait for another bite.