September on the Bass Rock 



petrels, unique amongst our British birds in still tending 

 its young in September. The period of incubation is six 

 weeks, and the young birds are not able to leave the Rock 

 until they have been tended by their parents for nearly three 

 months. Towards the end of the second week of September, 

 during a recent season, I spent some days on the Bass Rock 

 studying the bird pyopulation of the small island, and although 

 at times the weather was exceedingly stormy, I succeeded in 

 gathering a certain amount of information concerning the 

 nesting habits of the gannet in early autumn. 



On September 15, I should say that sixty per cent, of the 

 young gannets had made their first flight from the Rock, 

 while of the remaining forty per cent, many were in the 

 downy stage and would not leave the nest for another month. 

 One particular nest I had under observation contained a 

 downy youngster with his flight feathers just commencing to 

 sprout. 



After a storm of wind from the north-east, much seaweed 

 was floating on the surface of the water, and gannets were 

 everywhere busily engaged in repairing their nests. In one 

 particular instance, what I took to be the hen bird remained 

 at the nest guarding the young, while the cock made frequent 

 excursions to the water, returning with his bill full of sea- 

 weed. But on one occasion he appeared, carrying, not sea- 

 weed, but a billful of straw, which he deposited on the back 

 of the youngster. Instead of utilizing this straw for the nest- 

 building purposes, the mother bird left it severely alone, and 

 on the return of the husband a minute or two later with his 

 bill again full of straw, mixed with some seaweed, he found 

 his previous offering of straw quite untouched. And now a 

 quite noteworthy incident happened. Instead of depositing 

 both straw and seaweed in the nest, the male bird, apparently 

 taking in the state of affairs, solemnly dropped the seaweed 

 in front of his wife and then sailed off, still carrying in his 

 bill the unwelcome straw. 



The whole incident seemed to me to be a clear case of 



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