I'd say you're correct - and that map at the USDA has to be old, because I'm in MN and we absolutely have it here
We'll have to see - since we're not trying to make it like 'perfect' (i.e. we're going for the nature pond thing) I think it won't be too bad. We took a bucket of water from a local pond to jump-start things and so we've got a few (native thankfully) snails eating algae, a ton of boatmen, etc. so there's a mini-ecosystem starting. Hopefully it will not require too much in the way of upkeep, but if it does at least it's small...
still learning lemmy - didn't realize it was a picture at a time so here's the tadpole evidence
Frog Pond
So my wife decided that she wanted a pond for Mother's Day (like small garden pond - we live in the burbs) and so she got one.... Took longer than a day, but we at least started on Mother's Day. Anyway - her ultimate goal was to get a 'natural' pond set up and get frogs to spawn in the pond.... While we still need to do some work covering the liner at the top - it's in and we filled it with water like 3 weeks ago... We now have tadpoles!! And a pair of mallards are using it for like a love nest or something - they come and go throughout the day, splash around taking baths, etc. ...