Is it true that a shark can smell blood from a kilometer away? (5 photos)

Have you ever been afraid of getting hurt at sea? No? Very in vain. As soon as a drop of blood falls into the sea, they will come for your soul from the farthest corners of the ocean. Sharks. Ruthless predators, baring their fangs, will circle around until they drive you into a ring from which you will no longer be destined to escape.





Man, where are you? Cut yourself to give a signal.

This seems to be how they describe the supernatural ability of predatory fish to smell their prey, right? But how are things really going? How far can a shark smell fresh blood?

Let's start with something simple. What is smell? Ultra-fine particles of a substance that, due to their smallness and lightness, distribute well in the environment. How these particles spread is a matter of the state of the environment into which they fall. On land this is done by air currents, in water by currents.

Also, for the nose to smell the smell, there must be quite a lot of these microparticles in one place. No nose can smell one molecule among a trillion other substances. And in a moving and unstable environment, the concentration of substances quickly drops to a state in which it is not only impossible to recognize with the nose, but also impossible to catch these very particles.



Hello, I ordered a bloody Mary. If you don't bring it now, I'll make a Bloody Mary out of you!

And now you, reader, will ask me why I’m talking about physics and chemistry here, when we’re actually talking about sharks here. But everything described above simply affects the shark’s perception of odors! Because at one moment, due to the nature of the flow and the amount of blood shed, she can really smell the deliciousness even from this very notorious kilometer! But if the water is calm and there is only three drops of blood from the cut, the shark will not even know about your existence.





Hammerhead sharks have the most powerful sense of smell among sharks. But they use it not for hunting, but to find a soul mate.

In addition, the olfactory abilities of fish are too overrated. Yes, sharks have a sensitive sense of smell. Just as sensitive as their relatives - stingrays. Both are capable of detecting a drop of a substance in a ratio of 1 to a billion. It sounds like a lot, but in reality it is the volume of a small backyard swimming pool. If you decide to splash around with a shark wearing this, it will probably notice you, beware!



Girl, don't be afraid, I've got your back!

But it would be unfair to say that our blood is not at all interesting to sharks. The fish will really be interested in us if we empty out a whole bucket. This was proven in a visual experiment by science-pop blogger Mark Robert. He placed four buckets on the surfboard: with human blood, fish oil, urine and sea water. Each container was emptied simultaneously and evenly. A bucket of human blood gathered 41 sharks around it! And 4 predators were circling around the fish oil.



In general, we are not too tasty for a shark. The man is too thin. But pinnipeds, which are full of subcutaneous fat, are a completely different matter!

In the second part of the experiment, the blogger introduced the same liquids into water in a thin stream at a speed of 15 drops per minute. The same place, the same blood did not attract a single predator. As a result, he came to the conclusion: if you cut yourself and there is no fountain gushing out of you, you can rest easy!