Chapter XV 



ACCLIMATISATION WORK; GENERAL 

 CONSIDERATIONS 



IN the various experiments made in the attempt to acclimatise, or, 

 as I prefer always to call it, to naturalise, certain animals, very little 

 forethought was given as to the possibilities of any particular case. 

 We are wise now after the event, and we blame the acclimatisation 

 societies, the Government, or various private individuals for mistakes 

 made. But it is doubtful whether we would have done any better 

 ourselves. There is one curious fact which never seems to have entered 

 into the minds of most if not all of the acclimatisation enthusiasts, 

 viz., the migratory character of the species which it was sought to 

 establish in this new land. This applies especially, of course, to the 

 birds. It probably explains the failure of certain species to become 

 established here. Thus the blackcap (Sylvia atricapilla) and nightingale 

 (Daulias luscinia) are summer visitors only in the British Isles, the 

 former wintering in Southern Europe, Northern and Tropical Africa, 

 and the latter in Tropical Africa. Only a very few examples of these 

 two species were introduced, but it would "not have mattered how 

 many had been successfully conveyed to New Zealand, and liberated, 

 the result must have been the same. After a time the birds would 

 almost certainly have become possessed by the desire to migrate to a 

 warmer climate, but having no hereditary line of migration to follow, 

 they would probably have proceeded northwards and perished at 

 sea. There is no information at all as to the effect of the migratory 

 instinct on birds which have been taken from their own country to 

 a totally different hemisphere. We can only assume that the desire to 

 migrate would come on them strongly, and if so, it would inevitably 

 prove fatal to them in an island country like New Zealand. Seebohm 

 (in Siberia in Asia, p. 196) states that 



the migration of birds follows ancient coast-lines. The migration from 

 the south of Denmark over Heligoland to the coast of Lincolnshire seems 

 to correspond so exactly with what geologists tell us must have been the 

 old coast-line, that it is difficult to believe it to be only a coincidence. 



The following species which have failed to become established 

 in New Zealand are purely winter visitors in Britain: brambling 

 (Fringilla montifringilla), white-fronted goose (Anser albifrons), brent 



