A wild sea otter recently gave birth on a rock in waters surrounding the Monterey Bay Aquarium on the central coast of California. Aquarium staff and visitors witnessed the rare sight Saturday afternoon.

Stormy sea conditions are thought to have driven the pregnant female to the aquarium's Great Tide Pool. A video released by the aquarium shows the female otter writhing atop a rock as she labored and cared for her newborn.

This event marks the second time since December that a wild sea otter has used the aquarium's tide pool as a birthing center.

"It's not every day you get to watch a sea otter pup come into the world!" the aquarium wrote on Facebook. "Our sea otter researchers have been watching wild otters for years and have never seen a birth close up like this. We're amazed and awed to have had a chance to witness this Monterey Bay conservation success story first hand in our own backyard."

Sea otters can give birth in water or on land. In the video released of the birth, the mom sea otter is seen delivering her pup, pulling it up onto her belly for immediate grooming, which the aquarium explained will help the baby stay warm and buoyant.

Unlike most marine mammals, sea otters don't have a lot of blubber to keep them warm in cool ocean waters. Instead, they have the world's densest fur, made up of more than a million hairs per square inch in the thickest areas. To compare, humans generally only have an average of 100,000 hairs on their head.

To keep their fur waterproof, otters seal their fur with natural oils from their skin and fluff it with insulating air bubbles. Furthermore, grooming helps stimulate blood flow and gets other internal organs ready to consume and digest the food the newborn needs to gain strength.

Aside from having thick fur, sea otters stay warm by eating a lot, which essentially provides endless fuel for their bodies to burn and helps heat them up.

For the next two months, the sea otter mom will use her body as the pup's crib, carrying the baby on her chest until it has matured and shed its special coat of extra-thick fur that helps it float.

Once hunted to the brink of extinction, sea otter populations are finally starting to rebound. The live birth made for a special event, as most female sea otters give birth to one pup each year, generally in the spring or fall. Aquarium spokesman Ken Peterson said the pup's birth is a sign of species' recovery.