BRITAIN^S BIRDS AND THEIR NESTS. 161 



of Ailsa Craig at the entrance of the Firth of Clyde also 

 afford nesting - places for great numbers of these birds. 

 In fact, the British Solan colonies are sufficiently few 

 in number to be enumerated in fall. Nevertheless,' our 

 stock of Gannets is not small, for most of the colonies are 

 of great size. Two Scottish colonies have already been 

 mentioned ; but there are still four others — Sule Skerry 

 (' Solan Islet '), some forty miles west of the Orkney main- 

 land ; Sulisgeir (' Solan Rock '), a still more lonely isle, 

 about thirty-five miles north of the northernmost point of 

 the Lewis ; Stack -an- Armin and Stack Lii, both off Boreray 

 in the St Kilda group. Wales has one colony — namely, 

 that on Grassholm, off Pembrokeshire ; but England has 

 none, now that the one on Lundy Island in the Bristol 

 Channel has disappeared. Off the south-western corner of 

 Ireland there are two colonies, a large one on the Little 

 Skellig, and a smaller colony on the Bull Rock, seventeen 

 miles away. These, with a colony in the Faroes and several 

 off Iceland, make up the European list, for there are none 

 off Scandinavia. There are transatlantic colonies, however, 

 on some of the islands in the St Lawrence estuary and 

 elsewhere. 



At all seasons of the year Gannets may be found round 

 the greater part of our coast-line. For one thing, they 

 are birds of such strong flight that the areas which they 

 fish over extend for a considerable distance on all sides 

 from their nesting-stations. For another, a fair number 

 even of mature birds apparently do not breed in some 

 seasons ; and as the Gannet takes six years to come to 

 maturity, the number of immature, non-breeding birds 

 is consequently large. In winter, too, the nesting islands 

 are forsaken, and the species becomes more evenly dis- 

 tributed throughout our territorial waters. At this season 

 something comparable to true migration takes place ; but 



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