Debunking myths: NASA Engineer tests shark's blood detection skills

Former NASA engineer Mark Rober decided to investigate a common stereotype about sharks that fans of the children's movie Finding Nemo are familiar with. He introduced blood into the ocean to see if sharks could sense it from a distance of approximately 1.6 kilometres.

The scene from the well-loved children's movie "Finding Nemo," where Bruce, the great white shark, can't contain himself after smelling a drop of Dory's blood, has intrigued many, not just fans.

In real life, to see if sharks can indeed detect the scent of blood in the water, the former NASA engineer turned YouTuber Mark Rober set out to find the truth.

The 44-year-old travelled to an area known for sharks, 29 kilometres off the coast of the Bahamas, to carry out his experiment with a marine biologist and shark diving expert Luke Tipple.

He assured his audience that he had concocted a "solid testing method" and created "NASA-grade equipment" to dispel the long-standing belief that sharks go into a frenzy as soon as they detect the smell of human blood.

He explained regarding his experiment that his intention was to discover how far they could sense a single drop of blood in water, but first, he wanted to prove that they indeed prefer blood over any other scent.

He arranged four surfboards, each emitting about 7.5 litres of different substances: fish oil, cow blood, seawater, and urine. These substances were released into the ocean over an hour, and Mark and Luke observed from their boat, noting the number of sharks attracted to each board.

Four sharks approached the fish oil; none showed interest in the urine, but the board with blood drew as many as 41 sharks. Although it is hard to consider this experiment a scientific study, it clearly demonstrated that blood was, by far, the most intriguing scent to sharks. This disproves the surfer's myth about urine attracting sharks.

In the following part of the experiment, the YouTuber assessed the sharks' interest in surfboards from which drops of human blood were leaking. On the first board, a device was set up to release one drop of blood per minute, and on the second - one drop every four seconds. Over an hour, no shark showed interest in either board.

The engineer concluded that while this wasn't a flawless experiment, it's fair to say that since no shark was drawn to the board dispensing 15 drops of human blood per minute amidst waters filled with sharks, scratches are likely not a concern.