Grylfalcon

Link to tweet

The largest falcon in the world, the ghostly Gyrfalcon is a fierce predator in the High Arctic, where it chases down ptarmigans in flight or plummets from the sky at breathtaking speeds to strike prey to the ground. Nesting on remote cliffs in the far reaches of Canada and Alaska, Gyrfalcons in North America are safe from most human disturbance but face challenges from a warming climate. They are rare winter visitors to open habitats in the northern United States.

https://www.allaboutbirds.org/guide/Gyrfalcon/overview#