People often believe that just a small drop of blood falling into the ocean can be detected by sharks up to 400 meters away, prompting them to rush towards it. But is this true?
Sharks have highly sensitive sensory organs in their noses that help analyze smells accurately.
First, let’s explore how sharks “smell” that blood. When a drop of blood comes into contact with water, it dissolves, and the blood molecules disperse into the water. The current then carries these blood molecules away. If a shark encounters a water flow containing these blood molecules, its highly sensitive sensory organs will analyze the scent, allowing the shark to swim in the direction of the water flow with the highest concentration of blood molecules.
So, is one drop of blood enough for a shark to detect? It’s quite difficult because the number of molecules in a single drop of blood is very small. However, under favorable water conditions, those blood molecules can still reach a shark’s nose. Imagine it being similar to a person hearing a nail drop on the ground from 400 meters away in a truly quiet environment. In the ocean, achieving complete silence is nearly impossible due to various environmental factors that keep the waters turbulent, making it hard for blood molecules to travel far.
Moreover, studies indicate that sharks can detect blood at concentrations as low as 1 part per 1,000,000, meaning they can sense one drop of blood in 50 liters of water.
Therefore, a significant amount of blood and ideal ocean currents are required for sharks to “sniff” it out. The idea that sharks can detect a single drop of blood from afar is extremely unlikely.
Which Shark Species Has the Best Sense of Smell?
The long snouts of hammerhead sharks lead many to believe they have a keener sense of smell than other shark species. However, a 2014 study on the olfactory capabilities of 58 species of sharks and rays revealed that large shark species like the great white, tiger, and bull sharks possess the most developed sense of smell. These species have the largest olfactory organs, allowing them to detect scents over greater distances in the ocean.
In contrast, species like the shortfin mako or the longtail shark have less developed olfactory senses. This difference may be related to their diet. Sharks with a sharper sense of smell typically hunt stronger-scented animals like seals or scavenge from decomposing whale carcasses. Meanwhile, sharks with less acute senses often hunt smaller, less odorous prey.
Superior smelling ability is an advantage that helps sharks effectively hunt. Thanks to this sense, they can locate food from a distance, even when prey is hiding.
Sharks and Their Relationship with Humans
Although sharks have an incredibly sensitive sense of smell, fortunately, they do not seem to be interested in the scent of humans. Most shark species primarily use their sharp olfactory senses to hunt prey like bony fish or other marine animals, rather than targeting humans. This may explain why shark attacks on humans are quite rare.
In conclusion, a shark’s sense of smell is an extremely important tool that helps them survive and hunt in the ocean. Despite exaggerated myths about their ability to detect scents, it cannot be denied that sharks are some of the most keenly perceptive and effective predators beneath the waves.
