BOULDER STREWN beaches outside Port San Juan, Peru, about fifteen degrees 

 south of the equator, are the usual breeding ground of the Peruvian sea lions. 

 The mating season follows the whelping season almost immediately. Huge 

 males are fighting continuously with ambitious intruders and manage to hold 

 their harems together only by strength and stratagem. One great bull may 

 have as many as twenty females about him while other lovelorn males languish 

 in the background. Again, a single pair may be seen in the rookery. The aver- 

 age harem contains five or six females. Fidelity usually is limited to a season. 



^^i.^^J'^sf^i, ^iJiija!^— .-. 



