After a total gestation period of 11 to 11.5 months, sea lion pups are usually born on land, and are, on average, about 30 inches long, and weigh about 13 pounds. California sea lions are among mammals that have a special adaptation called “delayed implantation”. This allows the fertilized egg to delay attaching to the wall of the uterus for about 2 to 3 months. This assures the pups will be born during the best time of year for good weather conditions and abundant food sources.
Vocal cues, or sounds by the mother and pup sea lions may be the most important factor in mother-pup recognition. The female sea lion vocalizes often during and immediately after the birth of her pup. The pup instinctively replies. This vocal interaction may continue for 20 minutes or more. This helps establish the mother-pup bond. The mother may also smell, nuzzle, pull, and nip at her pup.
Most sea lion pups are born in late June. Pups are well developed at birth. They are born with their eyes open and can vocalize. Within 30 minutes they are able to shake, groom, scratch, and walk. Pups appear to be able to swim a little at birth, although they made need a little help from their mothers. Keepers from our Animal Care department have shared that it is always a fun experience to watch the sea lion mothers give their pups “swimming lessons” as they develop their coordination.
You can visit with Wheezie and her pup, along with the rest of our seal and sea lion community, daily at Rocky Point Preserve. Hope to see you there soon!