A super weaner (also super-weaner or superweaner) is an exceptionally large elephant seal at weaning age. Super weaners may reach their large sizes by stealing milk from nursing female elephant seals or by being adopted by an additional mother elephant seal.

Background

Elephant seals have an abrupt weaning process, in which the weaned juvenile seal does not receive assistance from its parents in finding food. The postweaning period is important for the seals' development, with a high

mortality rate Mortality rate, or death rate, is a measure of the number of deaths (in general, or due to a specific cause) in a particular population, scaled to the size of that population, per unit of time. Mortality rate is typically expressed in units of de ...

Phenomenon

A super weaner, an elephant seal at weaning age which obtains milk from multiple females, can weigh . A typical elephant seal at the same age weighs between and . While most mother elephant seals will bite weaned elephant seals that attempt to

suckle Suckle may refer to: *Suckling, or Breastfeeding *Suckle (band), Scottish indie pop band *Richard Suckle Richard Suckle (born January 1969) is an American film producer. Suckle was one of several producers nominated for an Academy Award for Be ...

, some will allow it for unknown reasons; some super weaners also obtain the additional milk through theft.

Instances

Three Mirounga angustirostris pups nursing

A study carried out on Año Nuevo Island in

California California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...

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." Male pups were more persistent and successful at stealing milk, and the largest weaners were universally male, including exceptionally large weaners which the study defined as "superweaners". 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. The study additionally found that the large weaner seals reach their large sizes through two distinct strategies: by stealing milk from nursing female elephant seals ("milk thieves"), or by being adopted by an additional mother elephant seal ("double mother-sucklers"). A 2014 study published in ''Proceedings of the Royal Society B'' explored the benefits of high

fat In nutrition science, nutrition, biology, and chemistry, fat usually means any ester of fatty acids, or a mixture of such chemical compound, compounds, most commonly those that occur in living beings or in food. The term often refers spec ...

stores in female northern elephant seals, which relate to their

buoyancy Buoyancy (), or upthrust, is an upward force exerted by a fluid that opposes the weight of a partially or fully immersed object. In a column of fluid, pressure increases with depth as a result of the weight of the overlying fluid. Thus the p ...

. 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 A rookery is a colony of breeding animals, generally gregarious birds. Coming from the nesting habits of rooks, the term is used for corvids and the breeding grounds of colony-forming seabirds, marine mammals (true seals and sea lions), and ev ...

. Costa suggested that super weaners are likely so buoyant that they have difficulty figuring out how to feed. A 2021 study, also in ''Proceedings of the Royal Society B'', removed super weaners from modeling analyses because it utilized "the assumption that a single mother nursed a single pup throughout the average lactation period". Super weaners were defined as weaners weighing more than . This study found that both male and female pups can become super weaners, although they are more likely to be male (64% of 94 super weaners measured).

In popular culture

In "The Maternal Combustion", a 2015 episode of ''

The Big Bang Theory ''The Big Bang Theory'' is an American television sitcom created by Chuck Lorre and Bill Prady, both of whom served as executive producers on the series, along with Steven Molaro, all of whom also served as head writers. It premiered on CBS ...

'',

Leonard Hofstadter Leonard Leakey Hofstadter, Ph.D., is a fictional character portrayed by Johnny Galecki in the CBS sitcom ''The Big Bang Theory.'' Leonard is an experimental physicist, who shares an apartment with colleague and best friend Dr. Sheldon Cooper. ...

compares

Sheldon Cooper Sheldon Lee Cooper, Doctor of Philosophy, Ph.D., Doctor of Science, Sc.D., is a Character (arts), fictional character in the CBS television series ''The Big Bang Theory'' and its spinoff series ''Young Sheldon'', portrayed by actors Jim Parsons ...

to an elephant seal pup who steals milk because Hofstadter feels Cooper is getting all the attention from Hofstadter's mother in addition to his own. Cooper replies that because both mothers are seeking to give him their attention, he is not a super-weaner, but rather a double mother suckler.

References

Citations

Works cited

* * * * * * * {{Refend Mirounga Marine mammals Animal developmental biology Buoyancy Animal physiology Reproduction in mammals