What is a sharks most sensitive means of finding prey?

Even though the shark uses both its eyesight and its sense of smell to hunt prey, neither one of those senses alone would lead it to enough prey to sustain its voracious appetite. The shark's eyesight is not very keen, and even though its sense of smell is good, smells do not travel well under water. As a result, these senses do not provide the shark with enough range to effectively hunt for prey. How, then, does the shark find enough prey to satisfy its appetite? The shark has two highly developed means of searcher for prey. A shark has a very sensitive vibration detector and an even more sensitive electrical field sensor.

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