BIRDS OF THE HUMBER DISTRICT. 75 



summer months along the Yorkshire coast and at 

 Flamborough, where there are some large colonies in 

 the sea cliffs. Congregates in August, leaving about 

 a fortnight earlier than either of the preceding. 



125. CYPSELUS APUS (Linnaeus). Common Swift. 



Provincial. Devilling. 



Forty or fifty years since, as old inhabitants in the 

 district have told me, nearly every village church in 

 our marshes had its attendant troop of Swifts ; but 

 this has long ceased to be the case, and they are now 

 very local in their haunts. Plentiful in the marshes 

 near Grimsby, where scores may be seen hawking 

 through the long summer days from early dawn 

 to late into the night *. There has been a decided 

 increase of this species with us during the last ten 

 years, although their decrease has been remarked 

 upon in other places f. A small colony have recently 

 established themselves in the fine old tower of our 



* It is astonishing the space passed over in a summer day by 

 the Swift. I have seen them on the wing at 4 o'clock, and as 

 late as 9 in the evening seventeen hours of probably almost 

 uninterrupted movement ; and calculating the flight of the 

 Swift at the average rate of eighty miles an hour, this gives 

 the amazing distance of 13GO miles in a single day. 



Mr. Macgillivray, in his 'British Birds,' vol. iii. page 622, re- 

 marks, " the Swift comes abroad as early as half-past two j and 

 I have seen it flying as late as half-past nine." 



t See Mr. Boul ton's remarks, in the 'Zoologist' for 1864, on 

 the gradual decrease of the Swifts in the neighbourhood of 

 Beverley. 



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