66 WILD LIFE OF SCOTLAND 



semi-starvation season to live through, like their 

 kindred on the land, the sea birds should increase 

 indefinitely. Besides, they have no enemies, except 

 an occasional peregrine falcon, or sea-eagle. A 

 shark has been seen to rise and engulf a diver, 

 and an ambitious cod to attempt a guillemot, just 

 as a pike will sometimes swallow a water-hen ; but 

 the occurrence must be too unfrequent to affect the 

 balance. 



Where the risks are great, the precautions for 

 the preservation, and continuance of the species 

 are exceptional ; and there is no better indication, 

 and gauge than the contents of the nest. Twelve 

 eggs, roughly, signify double the danger of six. 

 Keeping this in mind as we turn to the sea birds, 

 we find that the number of eggs is very much 

 smaller than in the case of the land birds. This 

 holds almost universally, with perhaps the excep- 

 tion of some of the ducks, whose nesting habits 

 expose them to considerable danger. 



A very common number is three. This holds 

 throughout the gulls, and their immediate kindred. 

 The terns' nests on the moor have three apiece. 

 This is well-nigh the maximum. In the case of 

 the skuas, it is reduced to two. The divers also 

 lay two. 



