Data from: Sources of variation in maternal allocation in a long-lived mammal

Life history theory predicts allocation of energy to reproduction varies
with maternal age but additional maternal features may be
important to the allocation of energy
to reproduction. We aimed to characterize age-specific
variation in maternal allocation and assess the relationship
between maternal allocation and other static and dynamic maternal
features. Mass measurements of 531 mothers and pups were used
with Bayesian hierarchical models to explain the relationship
between diverse maternal attributes and both the proportion of
mass allocated by Weddell seal mothers, and the efficiency of mass
transfer from mother to pup during lactation as well as the
weaning mass of pups. Our results demonstrated that maternal mass
was strongly and positively associated with the relative reserves
allocated by a mother and a pup’s weaning mass but that
the efficiency of mass transfer declines with maternal
parturition mass. Birthdate was positively associated with
proportion mass allocation and pup weaning mass, but
mass transfer efficiency was predicted to be highest at the mean
birthdate. The relative allocation of maternal reserves declined
with maternal age but the efficiency of mass transfer to pups
increases, suggestive of selective disappearance of poor-quality
mothers. These findings highlight the importance of considering
multiple maternal features when assessing variation in maternal
allocation.