COMPETITION BETWEEN GUILLEMOTS 195 



for the egg and for the helpless oflPspring ; 

 and, in the third place, it must be so situated 

 that the young can reach the water in safety. 

 We will examine these conditions one by 

 one. 



The proximity to the food-supply is a 

 consideration of some importance. The life 

 of the Guillemot during the winter is a 

 strenuous one ; we know that large numbers 

 succumb in stormy weather, and we can infer 

 that slight constitutional defects might make 

 all the difference between failure and success ; 

 and, therefore, the less severely the constitution 

 of the parent is taxed during reproduction, 

 and the more securely the constitution of the 

 offspring is built up, the greater prospect 

 will both have of resisting the hardships of the 

 winter successfully. Much, then, will depend 

 upon the distance the parents have to travel 

 in order to obtain food. The farther the 

 breeding station is removed from the feeding 

 ground the greater the physical strain which 

 will be imposed upon the birds, and the greater 

 the chance will there be of the offspring being 

 improperly nourished. Now the food consists 

 of small fish, largely of sand-eels, which are 

 secured in deep water, and the abundance of 

 which varies, possibly according to the nature 

 of the currents. Hence cliffs which are situated 

 away from the water, or from which the water 

 recedes at low tide, or which are surrounded 

 by an area of shallow water, and are thus not in 

 proximity to the feeding ground, even though 



o 



