In San Diego this year, two rare cases of mammalian twins have been recorded. In the wild off the coast of La Jolla Cove, a sea lion gave birth to two pups—a phenomenon that experts consider extremely unusual for the species. Simultaneously, at the San Diego Zoo Safari Park, a short-beaked echidna named Katherine hatched two puggles—babies the size of a gummy candy.
Typically, female sea lions give birth to one pup per season. The probability of twins is estimated at less than one percent, and such cases have not been previously recorded in the San Diego region. Observers from the Sierra Club Seal Society spotted the mother with two newborns in mid-June: one still had its umbilical cord, and the other had remnants of the placenta. Both pups, according to observations, are actively nursing and developing without human intervention.
The story with the echidnas is no less remarkable. These egg-laying mammals, or monotremes, normally lay only one egg per breeding season. Puggles spend about two months in their mother's pouch before moving into a burrow. In Katherine's case, zoologists discovered two babies at once. She is raising one in an underground burrow, while the second, weaker one had to be hand-reared at the veterinary center. Veterinarians are performing ultrasound examinations of the hand-reared puggle's stomach to better tailor its feeding regimen—the data is already helping to improve care for the species.
Both events are taking place against the backdrop of the San Diego Wildlife Alliance's active work in conserving rare animals. Short-beaked echidnas are not currently of major concern to the IUCN, but their long-beaked relatives are threatened with extinction. Observations of the twins provide a unique opportunity to study the specifics of digestion and maternal behavior, which previously remained little known.
Such rare reproductive successes serve as a reminder of how fragile and individual the survival strategies of different species are. Zoos and volunteer programs not only document these moments but also turn them into practical knowledge for future conservation efforts.
