Sea Lions and Pier 39 in San Francisco Bay have a long history, since September 1989 to be precise. It is believed that due to the earthquake the number of Sea Lions in the Bay area increased.
However, it appears that they actually feel safe in the Bay area and hence moved in large numbers. Whatever be the reason, Pier 39 is now not only famous for shopping, restaurants, street performances but also for Sea Lions.
Check out this video I shot