When Monterey Bay Aquarium officials noticed a wild female sea otter lounging in the aquarium’s Great Tide Pool lagoon last week, they were a bit concerned.

“It’s rare for a healthy sea otter to visit the pool so frequently,” aquarium staff wrote in a blog post. “We started to wonder if she was doing all right.”

On Dec. 19, just as the aquarium was closing its doors for the evening, staff saw the otter again return to the protected pool to get some sleep. The next morning, they found out why she’d been hanging around.

“Around 8:30 a.m., aquarium staff witnessed a new pup resting on her belly, being furiously groomed by a proud momma,” the aquarium’s blog reads. “We’re talking umbilical-chord-still-attached, whoa-is-that-yep-that’s-the-placenta new-born otter pup!”

The pup’s birth has been called evidence of a conservation success story because it wasn’t that long ago that the species was nearly hunted to extinction.

In the 1800s, there were only about 50 sea otters left, but today the Monterey Bay Aquarium says there are 3,000 of the animals in central California.

Below, check out a video and more photos of the wild otter and her newborn pup.

wild otter rests with her pup in aquarium's Great Tide Pool.The wild sea otter rests with her pup in the aquarium's Great Tide Pool. (Photo: Monterey Bay Aquarium)

The newborn sea otter pup snuggles with its mother.The newborn sea otter pup snuggles with its mother. (Photo: Monterey Bay Aquarium)