A 'traffic jam' on a one-lane penguin 'highway' worn deep into the snow cover at a Gentoo penguin rookery on Petermann Island, Antarctic Peninsula, January 2004. The bird on the left turned around and went back to an open area.
Gentoo penguins (the two birds with beaks raised to vertical) exchanging 'ecstasy calls', the greeting of one bird to another on return from the sea. Petermann Island, Antarctic Peninsula, January 2004