VOL. XV.] BUEEDING-HAHirs OF MERLIN. 195 



The nest is merely a cup in the ground lined with heather 

 (or bracken) debris that may chance to be there. During 

 the early stages of incubation the birds amuse themselves 

 by breaking off twigs from the heather within reach and 

 adding them to the nest. In several cases I have noted 

 small bits of bracken in a heather nest, but only if a bracken 

 patch happens to be within a few feet. 



The eggs — usually 4, very rarely 5 — appear to be laid 

 every second day, but the actual period of incubation I have 

 failed to determine, though it does not seem to commence 

 until the clutch is completed. Both birds then share in 

 the task, the hen on an average taking longer spells than 

 her mate.* I have only kept night watch over a single 

 pair of sitting birds and in that case at all events the male 

 incubated all night, but this may merely have been an 

 individual idiosyncrasy. The male now regularly does 

 the hunting, the hen but rarely being out ot sight of the 

 nest. The moment he arrives with food his mate meets 

 him, takes it and feeds, while he replaces her on the nest 

 and she proceeds to preen or doze on one of the higher 

 boulders. 



This year for the first time I had the good fortune to get 

 a pair of sitting birds to face the hide, and thus got a few 

 photographic records of incidents during the period of 

 incubation. Previous attempts had ended in desertion. 

 At this nest the birds had been sitting for nearly a fortnight 

 before the hide went up. As both birds tend to sit tighter 

 as time advances, it is sound policy not to hurry, particularly 

 as they show no worry at being watched from a greater 

 distance in the meantime. As stated above, the male sat 

 at night and alternated at intervals with the hen during the 

 day. As a rule, she would sit for about two hours before 

 being relieved by her mate for a period varying from one to 

 two hours. She was seldom away from the eyrie during 

 the cock's spell of incubation ; he was seldom present during 

 hers. She appeared to be fed entirely by him, always 

 taking her meals on the high ground above the nest, but 

 never on a boulder. On rare occasions during the day the 

 male would sit for short periods on one of the perches on the 

 high ground behind the nest, but as a rule he was away, 

 presumably hunting. The Tiercel was far more nervous 

 than his mate, and on being photographed would leave his 



* Birch at one time had four imitation MerUn eggs turned in 

 wood and stained brown, and found that the birds readily accepted 

 these as substitutes for the real thing. 



