Atlantic Puffin (Fratercula arctica) showing a little teritorial dominance. Northumberland, UK Atlantic Puffin (Fratercula arctica) showing a little dominace flapping it's wings to let the others know that this is it's patch of rock. Bright colouring dominates the bird in the breeding season as in this image. The behaviour is also indicative of the breeding season. Sand Eels form their main diet when breeing, so an important resource.