14 HOW TO IDENTIFY NEW ZEALAND BIRDS 
and other animals is sometimes peculiar. Cattle with 
birds on their backs are a familiar sight, whilst 
some Petrels are said to share their burrows with 
Tuatara lizards. The writer has seen a nest of a 
British Wren placed for protection or company in 
a lean-to between two chained watch dogs. 
Gregarious birds congregate together in search of 
food or to rear their young. Many, like Herons, 
live mostly alone but breed in colonies. Penguins, 
Albatrosses, Terns, and various other sea-birds 
assemble together in vast quantities during the 
nesting season, whilst Starlings, etce., roam about in 
great flocks searching for food in common. 
During the winter months, male and female birds 
often unite together in separate flocks, as is the case 
of Chaffinches, Buntings, ete.; whilst birds band 
together for protection when feeding, like Crows, 
which eat with sentries out to give the alarm. 
Hawks and other birds of prey are rarely 
eregarious, but a pair will often join forces, the one 
to drive, the other to pounce on: the prey. 
Generally speaking, gregarious birds, from their 
habit of flocking together and sharing all issues in 
common, are more abundant than solitary birds such 
as Ravens, Hawks, ete. 
As regards nests, the sites chosen vary much with 
the habits and localities frequented by birds. The 
majority of sea birds in the breeding season occupy 
every inch of available space on the ledges of cliffs, 
rocks, etc., there being so many of them that the 
fight for territory is often very fierce. Most Petrels, 
except the Giant Petrel (Macronectes giganteus) and 
the Albatrosses build in deep crevices or burrows, 
likewise the Penguins, though some species breed 
in the open as well. 
Most Parrots or Woodpeckers, ete., and many 
other timber frequenting birds raise their young in 
holes of trees. 
