San Francisco’s Pier 39 has become a magnet for sea-lion watchers after a giant Steller sea lion nicknamed “Chonkers” showed up and began drawing attention from both tourists and locals. On Thursday morning, visitors clustered around the docks to photograph the animal as it flopped among the much smaller sea lions that live at the popular waterfront attraction.

The Marine Mammal Center in Sausalito said Chonkers likely came from farther north, off the coast of Washington or Oregon. Laura Gill, the center’s public programs manager, said the Steller sea lion is estimated to weigh between 1,500 and 2,000 pounds (680 and 907 kilograms), making it markedly larger than the resident sea lions at Pier 39.

Gill said Pier 39 offers conditions that can make it especially attractive for a Steller sea lion. She said the pier is protected from predators and crashing waves while also providing a fish-filled buffet, and she pointed to a prey-rich San Francisco Bay as a reason the animal could find easy food there.

“There’s plenty of food in San Francisco Bay for them, so the fish, the rockfish, the anchovies, the herring, there’s a lot of easy prey for them,” Gill said, describing the types of fish available in the area.

Visitors who came to see Chonkers described how striking he looked compared with the sea lions they normally expect at the pier. Oluwaseyi Akinbobola, a Los Angeles visitor who said she had an extra half hour to go to the waterfront, said, “He’s like a Volkswagen! He’s so huge!”

San Francisco resident Danielle Ovadia said the sea lion’s presence has helped bring people together around the pier. “He’s so precious, and he’s quite literally humongous,” Ovadia said.

Pier 39’s sea-lion population is closely associated with the landmark after the 1989 Loma Prieta earthquake changed the local shoreline environment, according to marina information. A lone male sea lion was joined by others after the quake, and by February 1990, the pinniped population at the docks had grown to more than 300.

Gill said Chonkers has been spotted at the docks early in the morning but can be harder to see later in the day. She said it can be endearing to watch the larger animal attempt to snuggle with the resident sea lions for warmth and added that it will be interesting to see whether other Steller sea lions follow suit.

“He’s trying to fit in, but he sticks out like a sore thumb,” Gill said.