I saw this loon dive in the middle of the pond as i was driving by. I stopped and hid behind the guard rail and waited for it to surface. Recent roadside brush cutting has increased visibility from shore. The loon surfaced just a few metres off shore and i had to decrease my zoom to capture the loon in a single frame. As you can see the Loon remained low in the water and dove again quickly.
Based ONLY on the photos, I think they're American Golden Plovers, but I'd be happy to be corrected if I'm wrong.