Snow Petrel on Sea Ice in Winter
 - Pagadroma nivea

Snow petrels are birds of the Antarctic, they don't migrate as such but move further north in winter as the cold weather sets in. Research in recent years has shown that the Antarctic ocean beneath the winter ice is surprisingly rich in life - a fact that it seems these birds have known about for some time.  

They frequently arrive surprisingly far south in the winter in ridiculously low temperatures and high winds for such small creatures and rest overnight on totally exposed sea-ice, as here. Any spring and summer shelter is blocked up by now. The reason they venture south in such adverse conditions would seem to be in order to take advantage of the abundance beneath the ice and the relative rarity of summer competitors.