Des Moines area.... I imagine the river, fair grounds, Ankeny, to Adel area is not uncommon.. The way the area has spread makes it prime habitat to roam through.. Also at a time west Minneapolis to all along the south shore of Lake Superior was having lost pet problems I said it was big cats, until I was told ...what do you know.... Kind of a lazy Y pattern from south Florida up the east coast, and fanning across the mid west to the Black Hills, Big Horns, Rockies is usual sighting territory it seems...
Up here the pattern in usually up and down the west side of the Rockies in BC or the east side in Alberta...
There can be a black variation at time... For a crude comparison it can be as un common as a white, whitetail deer, but not an albino.. Also, here for instance, there can be an almost black grizzly bear variant.. A very rare thing.. Quite frankly... Unfortunately most people reporting a black cougar or grizzly are seeing it in lighting that leads them to miss identify... I could have miss colored the last grizzly to cross our place late last summer.... But not the shape...
Yes... At 50 to 100 kilometers square can be an average range of a cougar, depending on time of year, weather, shelter, water, food... This even for transient animals.. IE young males searching a territory..