Cocaine has been washing up on Florida beaches and floating in coastal waters for decades as drug smugglers relentlessly attempt to infiltrate the product into the United States.
Now scientists are examining whether the presence of these cocaine bricks has affected shark behavior, as thousands of sharks off Florida could be ingesting the dumped drugs.
In a documentary called "Cocaine Sharks," which is part of Discovery's Shark Week that starts this week, marine biologist Tom Hird visited the Florida Keys to investigate the sharks’ behavior.
"The deeper story here is the way that chemicals, pharmaceuticals, and illicit drugs are entering our waterways — entering our oceans — and what effect that they then could go on to have on these delicate ocean ecosystems," marine biologist Tom Hird told Live Science.
In the documentary, which airs Wednesday, Hird and University of Florida environmental scientist Tracy Fanara create an experiment with fake cocaine in packages similar to those the drug smugglers use and observe how a congregation of sharks exhibit intriguing behavior in response to the floating bales of fake cocaine, appearing somewhat agitated. One shark even swam away with a bale.
Subsequently, the duo also explored highly concentrated fish powder and noticed how it induced a dopamine response in sharks, akin to what cocaine might trigger in addicted individuals. Which led to sharks acting extremely hyper.
"I think we have got a potential scenario of what it may look like if you gave sharks cocaine," Hird said in the film. "We gave them what I think is the next best thing. [It] set [their] brains aflame. It was crazy."
However, Hird told Live Science that they still don't know what cocaine could do to a shark and that the experiment doesn't really show if sharks are actually consuming cocaine, but rather that they could also be consuming multiple other pharmaceuticals that land in the ocean, such as lidocaine, amphetamine, antidepressants, and even birth control.
In 2015, a U.S. Geological Survey revealed that fish nationwide were exposed to 17a-ethinylestradiol (EE2), a key component of oral birth control pills. This exposure resulted from the chemical entering waterways through human waste and the disposal of unused pills down drains.
Hird also said, that while the sharks did show similar behaviors to those of an addict, many other factors could explain their behavior, and more experiments, research, and blood tests are needed to fully confirm that these are indeed cocaine-consuming sharks.