220 AUSTRALIAN BIRD MAPS 



climbing. That is, it dies before maturity, as the 

 grubs generally go to the strong. 



The young of the White-tailed species may travel 

 with the parents as far north as the Ashburton 

 River, though it is more at home in the magnificent 

 forests of the south-west. 



THE NORTH-WEST SEA LINE 

 (Plate 2, Fig. 45) 



The north-west sea line is somewhat similar to 

 the north-east one, though not so rich in coral reefs, 

 or reef birds. There are those birds which keep to 

 the sand beaches, and many others common to the 

 mangrove estuaries. 



The Reef Herons are endeared to the atolls. 

 Many land birds cross the narrow sea to the low 

 lying islands. Petrels of the south rarely come so 

 far north, excepting that fine bird the Black-billed 

 Albatross of Lord Rothschild. It is so rarely seen 

 that we wonder if it is not the rarest of all the tube- 

 nosed birds. The "mutton-bird" is a type of petrel 

 that is said to migrate to the Japanese seas using 

 both dark and sunlight. Their nesting is mostly 

 nocturnal, a necessary evolution because of day- 

 light enemies, as skua gulls. 



The commonest of all our sea birds is the Noddy 

 Tern, found on the Houtman Rocks in nesting time, 

 and along the equatorial waters to New South 

 Wales. Elegant Tropic Birds, with attenuated red- 

 tail feathers, and great Frigate Birds lend charm 

 to the tropic seas of the north-west coastline. 



