114 THE NATURAL HISTORY 



LETTER IX. 



TO THE SAME. 



Fyfield, near Andover, Feb. 12, 1771. 

 DEAR SIR, 



You are, I know, no great friend to migration ; l and the well 

 attested accounts from various parts of the kingdom seem to 

 justify you in your suspicions, that at least many of the swallow 

 kind do not leave us in the winter, but lay themselves up like 

 insects and bats, in a torpid state, and slumber away the more 

 uncomfortable months till the return of the sun and fine weather 

 awakens them. 



But then we must not, I think, deny migration in general ; 

 because migration certainly does subsist in some places, as my 

 brother in Andalusia has fully informed me. Of the motions of 

 these birds he has ocular demonstration, for many weeks together, 

 both spring and fall : during which periods myriads of the swallow 

 kind traverse the Straits from north to south, and from south to 

 north, according to the season. And these vast migrations con- 

 sist not only of hirundines but of bee-birds, hoopoes, oro pendolos? 

 or golden thrushes, &c. &c. and also many of our soft-billed summer- 

 birds of passage ; and moreover of birds which never leave us, 

 such as all the various sorts of hawks and kites. 3 Old Belon, 

 two hundred years ago, gives a curious account of the incred- 

 ible armies of hawks and kites which he saw in the spring-time 

 traversing the Thracian Bosphorus from Asia to Europe. Besides 

 the above mentioned, he remarks that the procession is swelled 

 by whole troops of eagles and vultures. 



Now it is no wonder that birds residing in Africa should re- 



1 [In Harrington's Miscellanies (1781) is an essay " On the periodical appearing 

 and disappearing of certain birds at different times of the year," and another " On 

 the torpidity of the swallow tribe when they disappear " . Both are very sceptical 

 as to migration, and probably affected White's view of the question.] 



2 [Golden orioles (Oriolus galbula, L.).] 



3 [One or two species of hawks are migrants even with us : e.g. , the honey-buzzard 

 (see above, Letter XLIII. to Pennant), which comes in spring, and the rough-legged 

 buzzard, which is an irregular autumnal visitor. The kestrel migrates in winter 

 from north to south within our island. White's difficulty about these movements, 

 which he expresses in the next paragraph, does not admit of a complete solution, 

 nor can the movements of other birds be satisfactorily explained ; but to some 

 extent, no doubt, the hawks are influenced by the movements of the small birds on 

 which they prey (Harting) ; they will gather in numbers where there is a plague of 

 field-voles.] 



