32 BIRD MIGRATION 



although the casualties of travel and the attacks of 

 predatory species have more than decimated the flocks. 



' Imagine a mild and clear evening in spring. The sun 

 has set long ago . . . the last soft note of the redbreast has 

 died away, and for some time no sound has broken the 

 scented stillness of the air. Suddenly, the clear fine note of 

 our little wren is heard, and soon afterwards the little bird 

 is seen rising from the neighbouring bushes against the 

 luminous evening sky. At measured intervals its call-note 

 hut, hut, hut ! is heard as it flies off in slightly ascending 

 spirals over the gardens ; then from every bush, here and 

 there, near and far, the cry is answered, and from all sides 

 his travelling companions mount upward in the wake of the 

 earliest starter. Assured by the answering voices that all 

 the sleepers are aroused, he ceases circling about and rises 

 almost vertically with brief and rapid strokes. Soon all 

 assemble in a somewhat loose swarm ; the call-notes are 

 silenced when the last straggler has joined the departing 

 flock, and the tiny wanderers vanish from sight.' x 



One wonders how goldcrests and many other weary- 

 winged travellers relish the exchange of peaceful 

 shrubberies and tranquil market gardens for the clash 

 of arms and the shock of high explosives. No doubt 

 they still make use of Heligoland as a resting-place a 

 half-way house to the Continent, for birds are intensely 

 conservative in the route of their migration. Their 

 ancestors passed that way ten or twenty thousand years 

 ago, when what is now the North Sea was an expanse 

 of forest and marsh, and the birds have learnt, and will 

 learn, no other. In alighting on Heligoland they are 

 too weary to seek anything but rest. Even if food were 



1 Heligoland as an Ornithological Observatory, pp. 318, 319. Edin- 

 burgh, 1895. 



