Fifty years ago, if you wanted to see sea lions in San Francisco, you went to Seal Rock. (The name is proof that biologists didn’t name it; seals never hung out at Seal Rock, only sea lions.) This large chunk of sandstone had everything a sea lion could want: plenty of sun, plenty of water, plenty of fish, and plenty of other sea lions. Today, if you want to see sea lions in San Francisco, you go to Pier 39. So why the change?
Simply put, it happened because sea lions are many things but stupid isn’t one of them. (Smelly, noisy, aggressive, and cute as the dickens are.) Fishermen had been discarding the offal and bycatch from their trips for decades at Pier 39; it was well-known that sea lions would lounge around hoping for a tasty bit of fish guts. But when a couple of docks at the Pier were made temporarily vacant as part of a refurbishment plan, the sea lions moved in and basically took over. Within a few months, the sea lions had left Seal Rock and were happily making the fishermen miserable at Pier 39. Eventually, the fishermen moved out and the tourists moved in. Today as many as 1,700 sea lions can be seen at any given time at their new home on Pier 39.