Sharks may be consuming cocaine dumped in Florida waters and it could be making them act “crazy”, scientists said.
The researchers investigate whether drugs thrown overboard affected marine life in the region over a documentary that found that some sharks appeared to be acting strangely and others responded to similar stimulants.
Smugglers have left countless tons of cocaine in the seas around Florida, transported from South and Central America, either to be picked up by associates or to avoid arrest. The drugs are then often washed ashore by ocean currents.
Last month, the US Coast Guard seized more than 14,100 pounds (6,400 kg) of cocaine in the Caribbean Sea and Atlantic Ocean, with an estimated value of $186 million (£142 million).
Marine biologist Tom ‘The Blowfish’ Hird and University of Florida environmental scientist Tracy Fanara studied sharks off the Florida Keys to see if the drugs had any impact on them.
During a behavioral observation dive, a great hammerhead shark, a species that normally avoids humans, came right up to the team and appeared to be swimming awkwardly.
The researchers also recorded a sandbar shark that seemed to be obsessed with something and swam in tight circles, even though there was nothing in sight.
Fictional drugs trigger a feast of ‘crazy’ sharks
In addition to monitoring the sharks, the scientists also placed packages similar in size and appearance to real bales of cocaine in the water alongside dummy swans as part of their study.
To their surprise, the sharks headed straight for the bales, not the swans, and took bites.
One shark even grabbed a bundle and swam away with it.
Next, the researchers made a bait ball out of highly concentrated fish powder. This was designed to trigger a dopamine rush as close to a cocaine hit as the team could (and ethically) achieve in an experiment.
When the sharks ate the powder, the researchers watched them go crazy.
“I think we have a potential scenario of what it would look like if you gave sharks cocaine,” Hird said in the movie Cocaine Sharks, made for Shark Week on the Discovery Channel.
“We gave them what I think is the next best thing. (It) turned on (their) brains. It was crazy.”
Man dies after rare tiger shark attack
Endangered shark meat ‘sold in fish and chip shops’
Eventually, the team dropped their fake cocaine bales from a plane to simulate a real-life drug drop, and several species of sharks, including tiger sharks, made the move there.
The biologist conceded that many different factors could be responsible for the strange behavior and that the results do not necessarily show that the sharks in Florida are using cocaine.
Hird said: “We have no idea what (cocaine) could do to the shark.”
He added that the research shows that different fish appear to react in different ways to the same chemical, Live Science reported.
“So, we can’t even say ‘okay this is a baseline’ and go from here,” he said.
But he said he hopes the TV show, which will air later this month, will lead to more research in the area, and especially how pharmaceuticals of all kinds affect animals.