Super weaner

[1] A super weaner, an elephant seal at weaning age which obtains milk from multiple females, can weigh 600 pounds (270 kg).

[4] A study carried out on Año Nuevo Island in California between 1972 and 1977 observed the existence of some recently weaned northern elephant seal pups which either stole milk from nursing females or were "adopted by foster mothers."

These seals were "so large that their corpulence impeded their movements"; observation of two of them showed that their ability to acquire additional milk after being weaned was a major factor in their size.

[6] A 2014 study published in Proceedings of the Royal Society B explored the benefits of high fat stores in female northern elephant seals, which relate to their buoyancy.

[7][8] Daniel P. Costa, one of the authors, later stated that the findings might explain a known phenomenon in which super weaners are rarely seen again after departing the rookery.