Hutton. — Oar Migratory Birds. 259 



The evidence is therefore strong that both our cuckoos 

 leave New Zealand in the autumn and travel north-west to 

 New Guinea and the Solomon Islands, but we still want 

 evidence of the spring migration to the south. 



We have also migrations on a minor scale confined to 

 New Zealand, but very little notice has been taken of them up 

 to the present. Both the wry-bill plover (Anaryhnchus fron- 

 talis) and the little sand plover (Thinomis novce-zealandice) 

 breed in the South Island and pass tbe winter in the North 

 Island ; while the pied stilt (Ilimantopas picatus) seems to 

 perform some sort of migration, for it is found near Napier 

 in the summer, but not in the winter. However, it breeds 

 in both Islands, and its movements have not yet been made 

 out. 



The banded dotterel (Ochthodromus bicinctus) has been sus- 

 pected of migrating from New Zealand to Tasmania in the 

 autumn, for it is common in Tasmania in the winter and 

 leaves in the spring. The species occurs all through eastern 

 Australia, as well as in Lord Howe and Norfolk Islands. In 

 New Zealand it breeds in August and September, and is 

 equally abundant in the South Island all the year round, 

 showing no signs of migrating, and, as Mr. Handly reports 

 that it is also common in Marlborough throughout the year,* 

 I think that it may be safely affirmed that it does not pass 

 regularly to and fro between Tasmania and New Zealand. 



There are several other birds which do not migrate in 

 New Zealand, although they belong to genera, or even to 

 species, which migrate in other parts of the world. The 

 pectoral rail (Hypotmnidia pliilippensis) does not migrate 

 with us, although it does so in Australia, being a summer 

 visitor to New South Wales and South Australia, arriving 

 there in August and retiring northwards in February. The 

 New Zealand snipe (Gallinago aucklandica) and the brown 

 dotterel (Ochthodromus obscurus) do not migrate, and it was 

 so formerly with our quail (Goturnix nova-zealandia), al- 

 though all these belong to genera which migrate in other 

 parts of the world. In the cases of the New Zealand quail 

 and snipe, their powers of flight were so much reduced that 

 they were incapable of migration. But it is different with the 

 pectoral rail and grey dotterel. These fly well, but have lost 

 the migratory instinct. 



Now, what is this migratory instinct ? And what are the 

 reasons which induce, or have induced, birds to migrate ? 

 The principal cause of the migration of birds in the Northern 

 Hemisphere is, obviously, the food-supply, which for insect- 

 eating birds differs much in the summer and winter. In the 



* Trans. N.Z. Inst., vol. xxviii., p. 363. 



