342 G. O. Batzli et al. 



Males Females 



(/> 



>> 

 o 



T3 



00 

 CVJ 



> 



80 



40 



OL 

 80 



40 





 80 



40 



^^'^ 



Adults 



■^^iJ^ 



Subaduits 



> BOn 



8 



- Juveniles 



\J^- 



40- Sucklings 



*1 I I I I I I I 1 1 I I I I I I I I I I I I I I I I I I I lYlT l I I 



loop Juveniles 



F A J A D 

 Low 



F A J A D 

 Prehigh 



F A J A D 

 High 



Year of Cycle 



FIGURE 10-5. The density and demography of 

 brown lemmings through a standard three-year 

 cycle calculated by a population model. (After 

 Osborn 1975.) 



