Black Guillemot.
On a pelagic cruise at Witless Bay, Newfoundland, Canada on June 5, 2018, we saw thousands of nesting Black Guillemot. Cepphus grylle The Black Guillemot can stay underwater for up to 2 minutes and 20 seconds. source - https://www.allaboutbirds.org/guide/Black_Guillemot/