And I thought Lake Michigan was Safe...

http://animals.howstuffworks.com/fish/bull-shark.htm/printable

http://www.sharkattackfile.net/spreadsheets/GSAF5.xls

So, if you read the first article, you'll see that Bull Sharks have been sighted quite far up the Mississippi River.

The second is a spread sheet that I found on the Wikipedia page about Shark Attacks. If you alt+F for Chicago... It was 1955.

I guess I'm never going swimming at night again.

Swim at Your Own Risk

But that doesn't mean all of the Potomac shark sightings were the result of overactive imaginations. The lower Chesapeake Bay is an important nursery ground for the sandbar shark. The smooth dogfish and the sand tiger shark have also been known to frequent the bay.
In times of drought, when salinity rises in the bay and in the Potomac, sharks can swim upriver. Said Musick: "There are records of sharks up in the Potomac River that have involved bull sharks, which are nasty creatures."
A bull shark is what the crew must have dragged up near Chapel Point. Bull sharks have been spotted 1,000 miles up the Amazon, and the marine science institute's specimen collection includes an 8-foot bull shark taken from the mouth of the Potomac.
Most attacks on humans by sharks are accidents, but bull sharks are one of the few species that attack humans simply because they want to eat them.
Perhaps one day we'll see another fin slicing through the water near Washington. That would be kind of cool, actually.
"Yeah, it would," Dr. Musick said. "It would be appropriate, with all the other sharks up there."

What Smiff won't be doing this weekend: going to the beach

Search is on for killer shark

A retired veterinarian who was swimming with members of a triathalon club is killed in a shark attack north of Fletcher Cove. A marine expert said the wounds appeared to be from a great white shark, an attack he described as "practically unprecedented" in the area.
Swimmer killed by shark remembered as a 'great guy'
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