Reef sharks receive stimuli through the five senses that humans have: smell, taste, touch, eyesight, and hearing. However, they can also detect electricity and vibrations in water. First, the shark’s sense of smell is much stronger than a human’s. They can detect blood nearly 0.25 miles away. The nostrils are located on the underside of the snout and water always flows through the nostrils. This water relays information about smell to the shark. Sharks also have good eyesight. Their color vision helps them distinguish prey from the surrounding water. A shark’s pupils can dilate and contract to control the amount of incoming light that the retina is receiving. Not only does a shark have good vision and smell, but also good hearing. They are sensitive to low frequency sounds and are very good at determining where a sound comes from. They do not have ears but instead have endolymphatic pores on its head that lead to the semicircular canals, creating the sense of sound.

     To detect electricity, sharks have a special network of jelly-filled canals that detect electric fields. This lets the shark detect weak electrical stimuli from muscle contractions of other animals. They can even detect magnetic fields that some sharks can use for navigation purposes. In terms of detecting vibrations in the water, sharks use neuromasts, located on their back, that detect the intensity and direction of vibrations in the water.

     Blacktip reef sharks use their caudal fins to propel themselves through the water while the pectoral fins guide them. Therefore, when they react to a stimulus, they must swim in this manner to take action.