Have you ever wondered whether sharks prefer human blood or fish blood? You might think that ‘blood is blood‘ no matter what the animal, but is it? The chances for a shark to come across fish blood vs human blood are much higher, as other fish live side-by-side with sharks, whereas humans don’t. Humans only visit the oceans to scuba dive, to surf or to swim, which means sharks are less likely to recognise the smell of human blood vs fish blood.
Sharks prefer fish blood vs human blood and they are nearly 17 times more likely to be attracted to fish blood vs mammal blood, which in the experiment was cow blood. But the blood of mammals is very similar across all mammal species, which means that cow blood is similar to human blood.
The above information about sharks preferring fish blood vs human blood is demonstrated in the following video. Mark Rober teamed up with the Discovery Channel to film this experiment – Shark attack test – Human blood vs fish blood. This was filmed in the Bahamas where there are many sharks, including the beautiful tiger shark.
But if you rewind the video to the point where Mark is collecting fish blood, you will note he does this by creating a smoothie out of whole fish. A smoothie from whole fish is not the same as fish blood, as it contains the flesh, fat and organs of the fish too, which is going to be way more attractive to the sharks than blood on its own.
Whereas the mammal blood, which is to represent human blood in the experiment, is pure blood. It is for this reason that the experiment falls down. Having said that it’s very interesting to watch.
Do sharks prefer human blood or fish blood?
Sharks prefer human blood over fish blood because the smell of fish blood is wired into their DNA, meaning that sharks will know when a potential meal is nearby if a fish gets wounded. Sharks are opportunistic feeders like all predators, and if they are able to find an easy meal, they will take the opportunity.
Does blood actually attract sharks?
Sharks will react to blood in the water if the smell of the blood reaches them due to tidal movements, but it is more likely that fish blood will attract sharks rather than human blood. The sense of smell of sharks is not as well developed as many portray, which means if you cut yourself in the water, or if you are on your menstrual cycle, it’s unlikely this will actually attract sharks.
Do sharks attack when they smell blood?
Sharks are unlikely to attack humans when they smell blood, but they are likely to attack other fish if they get wounded. It’s not only the blood of fish that attract sharks, but it is the electrical signals they give out when they struggle when wounded. This is why it’s dangerous and provocative to hunt fish with harpoons with sharks around.
This can be seen in the following video of a bull shark attack on a spearfisherman. Not nice to watch as the shark gets hurt.
Before you go, you may be as fascinated as I was when I found out what fish eat sharks. In this article there are three amazing videos of other fish eating sharks whole: What Fish Can Eat Sharks, for me it’s the first video I was most amazed at.
But also, and if you are interested in sharks, you may like to discover more about oceanic whitetip sharks, which are extremely curious sharks and often when they are around scuba divers they look for openings or weaknesses. Two articles you may like to read about these aggressive sharks include Elphinstone Reef Shark Attack and Brothers Shark Attack: Oceanic Whitetip Shark Attacks Diver.
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