Okoboji Lake creature

Okoboji Lake is in Dickinson County in northwest Iowa. It is part of the chain of lakes known as the Iowa Great Lakes.. The East  lake is said to be not very deep , with a depth of 22 feet (7 metres). The West Lake however is estimated to be 140 feet (45 metres) deep. They are  described as  glacial potholes, a remnant of ice age 12,000 years ago..The towns of Spirit Lake and Okoboji sit on the   shore. Apparently it has  a monster within the lake. It is described as a giant fish with a head the size of a bowling ball and as being a dark green colour., Obojoki, as it’s been nicknamed by local residents, has been reported brushing against the sides of lake-users’ boats for many years.
One of the first
Mr. and Mrs. Charles Bartlett were at the lake a few days ago on a fishing excursion. They saw something, or rather saw where something was. They have no idea what it was. It might have been a sea serpent, or it might have been some kind of a fish that had grown to unusual and extraordinary size.They were out in the lake in a boat, when they noticed a short distance from them a terrible commotion in the water. The thing, whatever it was, was moving quite rapidly through the water and quite close to the top, and had the appearance of being as large as an overturned skiff. It made waves so large that Mr. Bartlett was really alarmed, fearing they would swamp his boat.He does not pretend to know what it was and declares he would not have believed there was such a creature in the lake had he not seen it with his own eyes the commotion made by it.
Source: Vindicator & Republican Estherville, Iowa July 3, 1903



There is also a you tube video of the satellite photo of the creature:
http://www.youtube.com/watch?v=Bq7vEYREzEw

 Then there is also this:
"One day (June 23 2001) my family and I were on vacation at lake Okoboji (in Iowa). We were at a small resort, with a dock.  I must make this clear, first: Okoboji is a huge lake. This lake was naturally made multiple dozens of thousands of years ago, and it is undoubtably hundreds of feet deep and possibly hundreds of acres from shore to shore. Anyways, my two children and I (one 10 and one 13) were sitting on the dock eating some icecream cones looking at the water. It was a calm evening, probably about 7:30 so it was still light outside but just starting to darken. The water was still, like glass, with ripples only from passing boats (no fancy boats, just normally cheap little things, and none came anywhere near close to us). When my 13 year old daughter nudged me in the arm and told me to "look here" and pointed at a waked spot in the water. it was churning, almost creating a small whirl pool.. A massive hump (well ok it wasnt that big but it was bigger than anything I wanted to see) slowly and gracefully rose out, about 1 foot away from the churning water. Then it moved quickly about 2-3 feet and rapidly went back under.  I remember it didnt have scales like a fish, more like a snake or maybe it had some kind of pattern that made it look like scales. It was dark dark dark greenish or blue. We were playfully "freaked out" while we watched for more, not thinking about the safety of us. Then, we saw a head... a very good-sized oval or sphere, a bit bigger than a bowling ball (but it wasnt perfectly round, it was like a lizard or a horse's head). The head arose, i could see it had the same pattern and colour as the hump i had previously seen. It had its head out and about 2 inches of its neck, and it swam very very very quickley through the water. The only part of its body that made the wake was its head, and i knew the creature must have been big, so it must have had a fairly LONG neck for its body to not disturb the surface. It swam probably a dozen yards, then its mouth opened, it appeared to take a gulp of air, then it went under. Just a split second later i saw the same hump role under the water, then i saw the last part of its tail  (it was a fairly stumpy tail) splash out. My children and I were too dumb-founded to say or do much. Then we saw its head again and it was coming toward our dock. About 1-2 feet away from the dock supports (the poles that hold it up), it went under. Less than a second later we felt a huge bump and a large "THUD" sound. The dock shook violently for a few seconds. By this time, we were terrified. we ran back to the shore as fast as we could.  http://theshadowlands.net/sightings.htm

So what was it? I think it may have been a Wels Catfish. It is a scale less fish and depending on it’s environment can be green brown in colour.  It is recognisable by its broad, flat head and wide mouth. They can live for 30 years and will eat anything and can grow to enormous sizes. What does anyone else think, a known fish or an unknown monster?

White men follow after: A collection of stories about the Okoboji-Spirit Lake region 

Lakes of Iowa: Lake Sugema, Clear Lake, West Okoboji Lake, Spirit Lake, Carter Lake, Lake Darling State Park, East Okoboji Lake