Sharks detect weak electrical fields using the ampullae of Lorenzini, a network of jelly-filled canals and sensory organs around the head. The receptors can sense electrical signals produced by living animals. They supplement other senses such as smell, vision and the lateral line.
Tiny pores connect to sensitive receptors
The visible pores on a shark’s snout lead to canals that end in electroreceptive cells. These organs respond to weak electric fields in seawater. NOAA describes the ampullae as sensory structures that help sharks detect electrical signals from prey. [1]
A close-range sense
Electroreception is useful when prey is hidden in sand or close to the shark. It is not a long-distance “radar” that reveals every animal in the ocean. Sharks combine electrical cues with smell, vision, hearing and movement detection.
Magnetic fields are a related but different question
Some research also investigates how sharks may detect Earth’s magnetic field, but the specific role of the ampullae and magnetoreception remains an active area of study. The well-established function of the organs is sensing weak electrical fields.
Can a shark sense a heartbeat?
It can detect weak electrical fields from nearby living animals, but the range and behavior depend on the species and conditions.
Sources and evidence
- NOAA Fisheries — Sharpen your shark facts ↗
Describes ampullae and electrical sensing in sharks.
- NOAA Office of National Marine Sanctuaries — Sharks in your sanctuaries ↗
Explains how ampullae of Lorenzini detect electrical fields.
Sources consulted: 11 October 2026. Written with AI assistance and checked against the linked references; not independently reviewed by a subject specialist. Sources do not endorse this article. See our editorial policy.
Revision: Initial publication; explanation checked against linked institutional and scientific sources.