I read in the newspaper this morning that a gentleman from Traverse City, Michigan found a dead shark in Lake Michigan. This did not surprise me. Rick Fasi discovered the two-foot long fish while boating and had it identified as a juvenile blacktip shark by an expert from the University of Florida. This species surprised me. I would have expected it to have been a bull shark. Let me give you some historical background on Lake Michigan and some surrounding freshwater rivers to explain why:
In September of 1937, the patience of Alton, Illinois anglers "Dudge" Collins and Herbert Copes was completely exhausted. More times than they cared to count, something—something big—had destroyed their Mississippi River fish traps while helping itself to a quick, easy meal. They guessed it was an opportunistic, gigantic catfish. They decided to end its marauding once and for all by setting a seine net to snare it.
When they returned they found that the trap had apparently worked, as the net’s buoys showed signs of a terrific struggle beneath the muddy water’s surface. What the men pulled up, though, left them shocked and scared. Ensnared in the net was a bull shark that was over five-feet long and 84 pounds. For those not familiar with bull sharks, here are a few facts:
- They can reach eleven feet in length.
- They are considered by divers to be the second most dangerous shark (after the great white). Unprovoked bull shark attacks on humans are not uncommon. Some studies have shown that bull sharks kill more humans per year than any other shark species.
- These unusual elasmobranches can not only survive in freshwater, but have been known worldwide to actually prefer it to saltwater. They are common inhabitants of—or visitors to—rivers that enter the ocean, such as the Ganges in India, the Zambezi in Africa, and our very own Mississippi and its tributaries.
Many authorities, presumably wanting to prevent panic among river dwellers and water-sport enthusiasts, insist that, due to the extensive lock-and-dam system built on the river shortly after the Alton catch, it would now be impossible for a shark to wend its way up the Mississippi, Illinois, or Ohio Rivers. That sounds comforting, but how can the authorities account for the following horror and oddity that occurred in 1955 and 1969 respectfully, well after the completion of the locks?
The day was beautiful, and consequently many were cooling off by boating or swimming in Lake Michigan. Among them was George Lawson, a boy from Chicago, who was swimming not too far from a boat off the shore. While splashing and playing, George was abruptly pulled underwater. Upon resurfacing, his screams for help brought John Adler to his rescue. Nevertheless, by the time he was brought into the boat, George’s right leg had been severed. The boat’s stunned passengers could do little but stare in dumbfounded awe at a large "tell-tale dorsal fin" that headed out to deeper water.
"I just couldn’t believe it, but I had to believe what I saw happening right before my eyes!" exclaimed a stunned Adler.
Doctors were certain that the boy’s injuries were inflicted by a shark, but were unable to explain from whence it came.
The second inscrutable encounter also played itself out on Lake Michigan. Anglers Gil Scharnek and Cal Lukasavitz literally stumbled upon a second shark specimen—much smaller, but a shark none-the-less.
"We saw a seagull sitting on what we thought was a piece of flotsam," recalled Scharnek. "When we got closer, the seagull flew away and we saw it was a fish. Cal said ‘Look, it’s a sturgeon,’ but when we got up to it we could see it was a shark."
The two brought the curiosity home with them, froze it and eventually had the identity of their find verified by a museum ecologist as a bull shark. Even though the lake’s temperature was a bone-chilling 42 degrees, the ecologist confirmed that even that was not too cold for a shark.Out-of-place animals have always fascinated me, but these sharks may have a purely biological origin...though blacktips are not known for their freshwater forays. The Michigan DNR, of course, proposed that "someone might have caught the shark of the Atlantic coast and kept it on ice while bringing it to norther Michigan." This begs the question: who keeps a two foot blacktip shark?