300 OUR RARER BIRDS 



bird is practically a resident there, for the St. Kildans never 

 think of searching for such an insignificant little creature as 

 the Stormy Petrel when once the big sea-birds have taken 

 their departure. This bird most probably pairs for life, and 

 its scanty nest of a few bits of dry grass is usually placed in 

 an old Puffin burrow or a rabbit-hole. Sometimes it lays its 

 eggs under heaps of stones like the Wheatear, or in crevices and 

 holes of walls and other masonry. The egg, for but one is 

 laid, is white, without any gloss, finely sprinkled with minute 

 red spots, which usually form an indistinct zone round the 

 larger end. The birds keep very close during the day, but at 

 dusk hurry out to sea, fluttering about over the rough ground 

 and far out on to the water in a very moth-like manner. The 

 Stormy Petrel only rears one young bird in the season ; but if 

 its egg is taken it always lays again, sometimes several in 

 succession, so that the breeding season is prolonged in many 

 places even into the autumn. 



The Fork-tailed Petrel is nearly twice the size of the 

 Stormy Petrel, and differs further in having a forked instead of 

 an even tail. This little bird escaped the notice of naturalists 

 until comparatively recent times possibly it was confused 

 with its smaller relation. The isolated position of its breeding- 

 place at St. Kilda, seldom visited by the naturalist, was 

 another cause of its remaining so long undetermined. Practi- 

 cally the Fork- tailed Petrel was discovered at St. Kilda 

 ninety years ago ; and it still continues to haunt those 

 remote islands, and to this day breeds there in abundance. I 

 have met with this interesting species in many of its haunts, 

 but my stay on St. Kilda gave me an unusual opportunity of 

 making myself thoroughly acquainted with its habits and 

 economy. 



The grand headquarters of the Fork-tailed Petrel at St. 

 Kilda are on Soay ; but an extensive colony exists on the 

 precipitous island of Boon. This island is a long, narrow 



