saprovores and the carnivores support the other important group of verte- 

 brate consumers, the "insectivorous" birds. Of these, the "shorebirds" 

 (sandpipers and plovers) are the most diverse and abundant. 



ABIOTIC VARIABLES 



INCOMING ENERGY 



X 



■ Increasing Moistu re 



Figure Bl. Interrelationship between major 

 abiotic and biotic components of the Barrow 



tundra. 



130 



