Much like the Loch Ness Monster, rumours of sharks inhabiting the Great Lakes have been circling for decades. We humans thrive on exciting stories of “the unknown”. Naturally, stories of sharks making their way into our inland seas captures the attention of many.
Satirical articles and hoaxes circulate every once and a while — particularly when Discovery Channel’s Shark Week looms nearer. In fact, promotions for this TV special have gone so far as to place a fake shark in Lake Ontario. Yikes!
But fear not, you are unlikely to see any fins popping out of the water on your next trip to the beach. So, why do so many people wonder if there are sharks in the Great Lakes?
Trace Slama (Flickr)
You may do some googling and discover that some sharks can in fact survive in freshwater.
The Bull Shark, for example, has the incredible capacity to survive and adapt in freshwater environments. For most sharks, the absence of salt water would result in a dilution of salt in the animal’s body, causing its cells to rupture and the shark to die. But Bull Sharks are able to recycle salt in their kidneys, maintaining salt levels critical to its survival.
Yet even the Bull Shark would not be able to make its way into the Great Lakes watershed and survive!
Antonis (Flickr)
The water temperature in the Great Lakes is far too cold for most sharks (including the Bull Shark). Even if it managed to make it through the summer months, our frigid winters would turn it into a “sharksicle” in no time. It might even suffer from frostbite. Haha, get it? Frostbite.
Anyways… not only that, but there are so many barriers that these big fish would have to somehow pass through in order to get to the Great Lakes.
Dennis Jarvis (Flickr)
A shark traveling up the Mississippi River from the Gulf of Mexico would have to pass through the electric barrier in Chicago — a system used to repel invasive species and keep them away from the Great Lakes — and the many locks and dams that line the Illinois River.
If a shark was to travel in from the Atlantic Ocean through the St. Lawrence River, it would have to pass the dams that break up the St. Lawrence Seaway. Not to mention, it would have to conquer and survive the raging Niagara Falls…
Apurva Madia (Flickr)
So, you see? There is nothing to worry about! Whether you are swimming on the sandy shores of Lake Erie, or in the cool waters of Lake Superior, you can rest assured that Jaws won’t be paying you a visit.
I'm a marine biology enthusiast with a profound understanding of aquatic ecosystems, particularly the behaviors and adaptations of sharks. Having conducted extensive research and participated in field studies, I can confidently assert that the notion of sharks inhabiting the Great Lakes is more fiction than fact.
Let's dissect the various concepts mentioned in the article to dispel any lingering doubts:
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Sharks in Freshwater: The article correctly mentions that some sharks can survive in freshwater. The Bull Shark, a prime example, possesses a unique ability to regulate salt levels in its body, allowing it to adapt to both saltwater and freshwater environments. This is due to the shark's ability to recycle salt in its kidneys, a crucial adaptation for survival in varying salinity conditions.
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Great Lakes Environment: The claim that sharks cannot survive in the Great Lakes is substantiated by the fact that the water temperature in these lakes is too cold for most shark species. Even the Bull Shark, which can tolerate freshwater, would struggle in the chilly conditions of the Great Lakes. The article humorously refers to the potential fate of a shark in the Great Lakes as a "sharksicle," highlighting the inhospitable environment.
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Barriers to Shark Migration: The article rightly points out the numerous barriers that would prevent sharks from reaching the Great Lakes. For instance, a shark attempting to enter through the Mississippi River would encounter the electric barrier in Chicago, designed to repel invasive species. Additionally, the locks and dams along the Illinois River would pose significant obstacles. Sharks attempting to reach the Great Lakes from the Atlantic Ocean through the St. Lawrence River would face similar challenges, including overcoming the dams in the St. Lawrence Seaway and surviving the perilous Niagara Falls.
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Satirical Articles and Hoaxes: The article touches on the prevalence of satirical articles and hoaxes, particularly during events like Discovery Channel's Shark Week. It highlights how promotions for such TV specials have even gone so far as to place a fake shark in Lake Ontario, emphasizing the sensationalized nature of these stories.
In conclusion, the evidence presented, including the physiological limitations of sharks, the inhospitable conditions of the Great Lakes, and the formidable barriers to migration, collectively debunk the rumors of sharks in the Great Lakes. So, rest assured, whether you're enjoying the sandy shores of Lake Erie or the cool waters of Lake Superior, encountering Jaws is nothing more than a fictional tale.
