Eastern hognose - Heterodon platirhinos. It's always helpful to give location when seeking ID. I'm pretty sure it's a plati but that one has an unusual pattern compared to the ones around here - doesn't help that ours are largely melanistic as adults.
the video was shot at a lake close to Parry Sound , Ontario. At a lake called Snake Lake , coincidentally, lol.
I had thought it looked like a hognose , but I wanted another opinion from someone who could tell me definitively.