They can't climb trees, but they are excellent and determined climbers. Lower water levels won't be effective, you need more of a fence/wall around this pond. They are excellent diggers as well, so a fence would need to be at least a foot underground. They are susceptible to flying and furry predators (large birds, cats, dogs, raccoons...), so you may need some sort of fence above the pond as well.
You'd also need shade, water heaters (water should be in the mid-70's) and some sort of filtration.
They are native to the Mississippi river, not sure about Iowa.
how to post a pic...
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