The arctic skua breeds in the northern hemisphere, on open spaces inland, on coastal flats and islands, from the Arctic circle to as far south as northern Scotland. Each pair occupies its own territory on moorland, tundra or shingle and in an unlined shallow scoop the female lays two eggs. The breeding birds eat a range of food from small mammals and insects to other birds, their eggs and young.
The arctic skua migrates south around September and passes through the tropics to winter in the southern hemisphere. They are common in New Zealand waters from November — April and, during that time, are the most numerous skua seen off the coasts of the mainland and the Chatham Islands. They sometimes join roosting flocks of terns or gulls. It is usual to see them harrying white–fronted terns or small gulls which they may force to drop or regurgitate fish.
