With so much cocaine in the waters, Tom “The Blowfish” Hird wanted to find out if thousands of sharks off Florida ingest the discarded drug and if they did, if the drug had any effect on them. On Cocaine Sharks, part of Discovery’s Shark Week, Hird and University of Florida environmental scientist Tracy Fanara conducted a series of experiments to find out.
Sharks behaving unusually
“The deeper story here is how chemicals, drugs and illicit drugs get into our waterways — our oceans — and then what impact they can have on these sensitive ocean ecosystems,” Hird told Live Science.
Hird and Fanara set their sights on the Florida Keys, where fishermen tell stories of sharks consuming drugs transported to the area by ocean currents. On the show, they dived with sharks to investigate unusual behavior and began seeing sharks acting in unexpected ways.
The great hammerhead (Sphyrna mokarran), a shark species that is normally wary of humans, has been observed swimming strangely, coming directly towards team members. In a shipwreck 60 feet (18 meters) below the surface, Hird encountered a sand shark (Carcharhinus plumbeus) swimming in narrow circles, seemingly fixed on something, despite nothing in sight.
They did different experiments
To investigate further, Hird and Fanara designed three experiments to see how sharks responded to bales of “cocaine” released into the water, creating packages that were similar in size and appearance to real bales of cocaine. In the first, they put these fake bales next to the puppet swans to see what the sharks were going for. Surprisingly, the sharks headed straight for the bales and took bites from them. A shark even grabbed a bale and swam away with it.
In the next experiment, they made a bait ball with a high concentration of fish powder that would cause the sharks to increase dopamine. This was done to give the closest response to the cocaine effect, and the sharks were found to react wildly. “I think there’s a potential scenario of what it would look like if you gave the sharks cocaine. We gave them what could have been similar, and it fired their brains. It was crazy,” Hird said. said.
Cocaine isn’t the only problem in the oceans
Finally, the team threw bales of fake cocaine out of an airplane to simulate a real-life drug crash, and several shark species were activated, including tiger sharks (Galeocerdo cuvier).
Hird said their findings don’t necessarily indicate that sharks in Florida are consuming cocaine. “Many factors can explain the behavior observed during filming, and these experiments need to be repeated over and over to come to full conclusions,” he said.
And the problem may not be just cocaine. “The other thing we might find is actually caffeine, lidocaine, cocaine, amphetamines, antidepressants, birth control pills, and their drift from cities into the ocean… It’s starting to hit animals,” Hird said.