When you go to get the hook outta the fish, according to how deep the hook was you can rub a knuckle inside and lose the skin. Catfish knuckles are a thing, kids.
That’s the limit to their biting ability.
Of course bigger catfish, bigger mouth and lots more of the sandpaper mouth. So they could do some harm if you’re effin’ sticking your arm down their throat. 
Yeah, if the catfish was capable of taking off a finger, noodling wouldn’t be a thing. Meanwhile alligator snapping turtles are definitely a thing, too.
My understanding is they feel around with their feet. I assume they have some kinda boot on. Maybe not tho’.
They learn to tell the difference between turtles, crawdads, other snappy critters pretty quickly. When they decide it is a catfish then the arm goes down. If you know how to grab a fish by the mouth/gills it helps.
Certain times a day the fish are lazy and bigger catfish are not apt to jump out of their mud bed. It’s easier to find bigger ones..not the UL size of course. But bigger than you can catch with a pole and a worm.
(Hand fishing/noodlin’ is a long held tradition. Hey, Jeremiah Johnson was purported to be very bad at it)
The things you worry about on a catfish are the front fins, modified into spikes. The divers should worry about being skewered, not swallowed.
In the documentary mentioned above, I don’t remember much in the way of footwear.
I’m pretty sure catfish noodlers do it barefoot.
ETA: Not catfish, but today while was fishing for bass at a local lake (really just a wide spot in a river), I saw two carp cruise by that must have been four feet long each, and probably as thick as my thigh. I’m glad I didn’t get a hookup with either of them - they would have pulled me in!
I can buy that. The places they’re going could be frought with numerous biting things, poking thing…some with poisons on board, tho’
Think I’d wear waders or something. But, hey, that’s just me.
Yep. Pro-tip: if you’re in danger of going in, sacrifice the tackle.
And say Carpe Diem
Hopefully they weren’t the leaping Asian carp.
Nope. I don’t think those have made it to California. Yet.
Better hope they never do.
Big Bear Lake has the story attached:
To be fair, there are catfish that can top 9’, but none in North America. The Mekong giant catfish (Asia), the Wels catfish (Europe & western Asia), and the Piraíba (South America) can exceed 9 feet in length. In North America, our 9-foot catfish are strictly catch-and-exaggerate.
Yeah. As it’s been said.
But the Urban Legend is just that. A legend.
Some legends can turn out to be true. This one just seems not in the biology of the fish here. I mean you can have a tiny frog. It’s DNA tells it how big to get. You might have the odd outlier that’s huge. But generally speaking they’ll be within the norm.
I assume (not one of the -ists that mean fish smart person) there’s a normal size, given variables in place or foods available, and the different exact species of catfishes.
One never knows.
Catfish never stop growing, although their rate of growth slows as they mature. This is called indeterminate growth. Factors such as food resources and water temperature affect the rate at which they grow. A very long-lived Wels catfish, for example, can grow huge.
The wels catfish is a long-lived species, with a specimen of 70 years old having been captured during a recent study in Sweden.
I heard an adjacent urban legend. About freshwater sharks snacking on campers.
“Freshwater sharks don’t exist!”
“Well no, but catfish can get pretty big. And hungry.”
“Catfish don’t get that large.”
“Hand me the Guinness [Book of World Records]!”
We then read about a preposterously large catfish from Asia with much panic and hilarity, depending upon your innate skepticism.
ETA: What’s the significance of the dam? Why do giant catfish appear in such an environment (according to the UL)? I see from Reddit that there are longtime reports of catfish in the Ohio River as big as a VW Beetle.
BTW: Scuba masks magnify objects by 25%.
Plenty food. Deep water. Lots of oxygen. Hidey holes.
Maybe not, but Bull Sharks are able to tolerate fresh water. From wikipedia: “The bull shark is diadromous, meaning they can swim between salt and fresh water with ease…” They have been reported many miles upstream in rivers throughout the world.
What about the dreaded Land Shark?
“Candygram.”
