Shark attacks are extremely rare (opens in a new tab) It’s unlikely you’ll meet one in person, let alone bite you. But during World War II, the sinking of a US Navy ship led to one of the most infamous shark attacks in history and the deaths of hundreds of men, with the explosion attracting apex predators. and causing a feeding frenzy that lasted for days.
In July 1945, the USS Indianapolis had completed a voyage to a naval base on Tinian Island in the Pacific to deliver uranium and other components that would be used to create the “Little Boy” atomic bomb. He first nuclear weapon once used in wartime, it would later be dropped on the Japanese city of Hiroshima.
After delivering the parts, the Indianapolis left for the Philippines on training duty. Shortly after midnight on July 30, the ship was torpedoed by a Japanese submarine, causing massive damage. She began to absorb large amounts of water and sank in just 12 minutes. Of the 1,195 men (opens in a new tab) on board about 300 went down with the ship, but almost 900 were left adrift in the open sea.
Many died from exposure, dehydration, and saltwater poisoning. However, according to Smithsonian magazine, it is estimated that up to 150 sailors and crew members were killed by sharks, in what is considered the worst shark attack in history. But why?
Dangerous sharks and how they hunt
Unlike other predators, such as lions and wolves, most sharks hunt alone, Nico Booyens, a marine biologist and director of research at the Shark Research Unit (opens in a new tab) in South Africa, he told Live Science in an email. “Different shark species have different hunting techniques, but many sharks are solitary predators that rely on their senses of sight, smell, and electroreception to locate their prey.”
Sharks also have a special system called lateral line (opens in a new tab) that picks up vibrations in the water, says Booyens. This sensory ability would have allowed them to detect the movement of men in the water as they thrashed to stay afloat. Once the sharks located the sailors, they had little chance of survival, especially those who were injured.
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According to survivor accounts, many victims were attacked near the surface of the water. This has since given rise to suggestions that oceanic whitetip sharks (opens in a new tab) (Carcharhinus longimanus) were the ones involved in the attacks because they are a surface-dwelling species (opens in a new tab).
“When a shark has located its prey, it often uses its sharp teeth and powerful jaws to bite down and tear off chunks of meat from the prey,” Booyens added. “Some sharks, like the tiger shark [Galeocerdo cuvier]are known for their ability to swallow their prey whole, while others, such as the bull shark [Carcharhinus leucas]It will attack and bite its prey repeatedly until it is weakened or immobilized.”
Although oceanic whitetips are at the top of the food chain, their meals can be few and far between, so they are often opportunistic eaters. According to the Florida Museum (opens in a new tab)the species is often the first to appear at the site of ocean disasters, and was also a leading cause of death after the sinking of the RMS Nova Scotia in 1942. The species is known to be persistent, unpredictable, and shows little fear , making it particularly dangerous to humans, the Florida Museum said.
The worst shark attack in history
On the USS Indianapolis, the bodies of the dead and wounded were collected first. Surviving Corporal Edgar Harrell told the Indianapolis Star (opens in a new tab) in 2014: “That first morning, we had sharks.” As the men got separated, they would come under fire,” she explained. “You hear a blood-curdling scream. And then the body would sink, and then that life jacket would reappear.”
The men were too scared to eat or move, for fear of being attacked. According to the report of a survivor, one of the sailors opened a can of Spam, the main ration at the time, but was surrounded by sharks, resulting in a “feeding frenzy”.
“Feeding frenzies generally occur when there is a sudden abundance of food, such as when a large school of fish becomes trapped in a small area,” Booyens said. “The scent of blood and the beating of prey can trigger a feeding frenzy, causing sharks to crowd together and compete for available food.”
Many species of sharks can engage in a hunting frenzy, during which they can become very aggressive, attacking each other and their prey. However, the opportunistic feeding behavior of oceanic whitetips, as well as their size and strength, made them particularly dangerous to sailors. “Feeding frenzies can be dangerous to humans in the water, as sharks may not be able to distinguish between prey and people,” Booyens added.
For four days, no rescue arrived. Although the US Navy had received word that a Japanese submarine had sunk an American ship, the message was believed to be false, in an attempt to lure American rescue boats into a trap. Meanwhile, the survivors tried to stay alive by floating in groups, but in the searing heat, many succumbed to dehydration. Others died of hypernatremia (too much sodium in the blood) from being forced to drink salty seawater.
Eventually, a Navy plane overhead saw the Indianapolis survivors and radioed for help. Food, water and rafts were dropped for the surviving men, before Lieutenant Adrian Marks landed a seaplane to rescue some of the survivors from the sharks. Eventually, the USS Cecil J. Doyle helped pull the remaining survivors out of the water. Only 316 men survived.