Scientists suggested in research that sharks may be ingesting cocaine which is being dumped in the ocean near Florida, which could be causing them to act in "crazy" ways.
While looking into whether drugs dropped overboard have an effect on the areas of marine life for a documentary, researchers revealed that some sharks appeared to be acting abnormally, and others responded to comparable stimulants,
Numerous tonnes of cocaine that had been smuggled from South and Central America had been dumped by smugglers in the ocean surrounding Florida, either to be collected by associates or to avoid getting arrested, which are then frequently carried ashore by ocean currents.
Sky News reported that more than 14,100 pounds (6,400 kg) of cocaine was seized by the US Coast Guard in the Caribbean Sea and Atlantic Ocean, with an estimated value of $186 million (£142 million) last month.
Tom 'The Blowfish' Hird, a marine biologist, and Tracy Fanara, an environmental scientist from the University of Florida, examined sharks around the Florida Keys to determine whether the drugs had any effect on them.
A great hammerhead, a species that typically avoids humans, approached his crew directly as they tried to study behaviours, and appeared to be swimming strangely.
Additionally, despite there being nothing in sight, a sandbar shark was observed swimming in close circles and seemed concentrated on something according to the researchers.
The scientists monitored sharks and placed cocaine bales in the water alongside dummy swans and they observed that the sharks seemed to prefer the bales, taking bites from them.
The researchers created a bait ball with concentrated fish powder to trigger a dopamine rush as close to a cocaine hit as possible in an ethical experiment. The team of researchers said that as soon as the sharks ate the powder, the deadly sharks "went wild".
"I think we have got a potential scenario of what it may look like if you gave sharks cocaine," Hird said in the film Cocaine Sharks, as part of Shark Week on the Discovery Channel.
"We gave them what I think is the next best thing. [It] set [their] brains aflame. It was crazy."
As a final step of their research, the researchers imitated an actual drug drop by dropping their phoney cocaine bales from an aeroplane, and several shark species, including tiger sharks, moved in.
The researcher acknowledged that a wide range of causes might be to blame for the peculiar conduct, and the findings don't necessarily indicate that sharks in Florida are ingesting cocaine.
Hird said: "We have no idea what [cocaine] could do to the shark."
He added that research suggests that different fish seem to react in different ways to the same chemical, Live Science reported.
"So we can't even say 'well this is a baseline' and go from here," he said.
However, he believes the television episode, which will premiere later this month, would spur additional study in the field, particularly about the effects of all kinds of drugs on animals.