SAN FRANCISCO (KPIX 5) – A new study shows that the sea lions that have become so ubiquitous at Fisherman’s Wharf in San Francisco are thriving everywhere, with the sea mammals numbers tripling in recent years.

In 1989, the first sea lion showed up at SF’s Pier 39. Soon hundreds more arrived to laze about the dock, creating a delightful, but totally unplanned tourist attraction.

“It was a blessing, but at the beginning we thought, you know, ‘What are we gonna do here? How are we gonna handle this?'” said Pier 39 Harbormaster Sheila Chandor.

It turned out the best way to handle them was to leave them alone. A new study proves how important that approach has been to the species in general.

The National Oceanic and Atmospheric Administration just published a long-term study showing that the California Sea Lion population from Mexico to Vancouver Island has risen to an all-time high.

“It’s really great news,” said Dr. Shawn Johnson from Marine Mammal Center of Sausalito. “It shows that this marine mammal that was under threat of near-extinction back before the Marine Mammal Protection Act has rebounded.”

The NOAA study says sea lions — which numbered only about 90,000 in the early 1970s — are now up to more than 280,000 and are at capacity for a healthy environment. Dr. Johnson says the turn-around began when the government banned the killing of marine mammals by those trying to protect fisheries.

“You can link it right back to these protections from the Marine Mammal Protection Act and the Endangered Species Act that have really protected these species from threats. Human threats mostly” said Johnson.

There are still natural dangers: warm El Nino currents depleted the food supply, killing thousands in 2015. But the report shows how quickly the population can return if man stays “hands off” and allows nature to take its course.