The scent of blood is one of the most striking to animals in general, and sharks are no exception. These animals have the ability to detect the aroma of blood even in very small amounts, from a fairly large distance. In addition, sharks can swim in relatively shallow waters to capture their prey, which makes them quite dark in the beach areas. However, sharks are limited by the distance and speed of their swimming, which varies depending on the size of the shark.
Sharks persist the aroma through water by two methods, diffusion and water currents:
The method of diffusion is too slow, and it consists of dispersing blood molecules slowly through water, diffusing it and diluting it with water as you move away from your starting point.
The method of the water stream consists of the travel of the blood by the movement of water. This is the fastest method for odors to travel through water.
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Depending on how fast the water moves, the smell of blood can reach a shark that is a minute or twelve or more minutes away, depending on how far away the shark is.
The distance gets an effect on the sense of smell of the shark
The only way a shark can react instantly to the smell of blood is if it is near the place where the blood was spilled. Most of the time it takes several minutes for a shark to sniff the blood and several more minutes for it to reach the site of the spill. Sharks swim in the current where they detect the smell of blood. To begin with, if they are a mile (1.6 km) away, it is very difficult for them to detect the smell of blood, but from a much shorter distance, such as a quarter of a mile (0.40 km), the shark has a good occasion to detect a strong aroma. The hunting sharks swim in spirals to remove the currents that do not bring the smell of blood and to follow those that do.
Sharks have a special sixth sense called electroreception.
This ability to receive electrical impulses helps them detect the electric waves that all living beings emit, alerting them of their presence.
