Sharks would be very rare but possible, they cant live indefinately in fresh water.

Five foot cats I believe are definately possible. The two previous world records were both 4'10" in length for blues. I believe the flatheads were longer. There are accounts of fish approaching 150lbs caught by commercial fisherman in the late 19th and early 20th centuries but there is no solid proof of fish of that size. We all know how fish seem to grow after being caught.

What about alligator gars? They are several confirmed fish in the 9-10ft range! That is just amazing to me.

With the improving conditions of America's large rivers I think its only a matter of time before another all tackle record is taken and it could be in our own back yard. An interesting note, I have a friend that is a fisheries biologist who once did a small sampling of large cats inthe 50lb range. They found drum approaching 5lbs in their stomachs so maybe instead of using large shad for bait some one needs to get a giant hook and fidsh a live drum! It doesnt take "that" big of a flathead or blue to **** down a 2lb drum and maybe that real monster just turns up its nose when a bite sized shad drifts by. Hehe Another interesting note, bullhead catfish make up a large percentage of an adult flathead's diet, any one ever use those for bait (if legal)?