INTRODUCTION 21 



ber of a million birds. They are not truly 

 Australian, though they live with us during six 

 months of the year. 



The young are reared in Northern Asia, and 

 brought as far south as Tasmania to get away from 

 the northern locking up of food. 



Apart from this great migrating stream, a^ a^ a^ 

 map 6), there are minor doings in travel as under: 

 Daily migration : 1. Up and down valleys (New 



South Wales). 2. From range to sea (Queens- 

 land). 

 Bathic migration : Plains to higher mountains 



(Spring-autumn) . 

 Partial migration : Annual e.g., Southern Victoria 



to Northern New South Wales. 

 Periodic migration : Subject to droughts and 



plagues. 

 Accidental migration: Internal and external. 

 Extra Australian : Within the Australasian Region 



e.g., from Port Augusta to New Guinea and 



islands. 

 Migration beyond Australia has its reverse side, 

 as shown in map 7. A truly marvellous silent mass 

 of life sweeps down from China and Transbaikalia 

 into the Malay Peninsula and New Guinea after the 

 summer of the northern hemisphere. This is in 

 July. Also at that time thousands of southern 

 Australian birds, wintering in New Guinea, leave 



