Data for: Faster growth and larger size at crèche onset are associated with higher offspring survival in Adélie Penguins

We conducted the first assessment of Adélie Penguin chick survival that
accounts for imperfect resighting. We found that when chicks are larger in
size when they enter the crèche stage (the period when both parents forage
at the same time and chicks are left relatively unprotected), they have a
higher probability of survival to fledging. We investigated the
relationships between growth, crèche-timing, and chick survival during one
typical year and one year of reduced food availability. Chicks that
hatched earlier in the season entered the crèche stage older, and chicks
that both grew faster and crèched older entered the crèche at a larger
size. These relationships were stronger in the year of reduced food
availability. Thus, parents increased their chicks’ chance of fledging if
they provided sufficient food for faster growth rates and/or extended the
length of the brood-guarding period. Early nest initiation (i.e., early
hatching) provided parents with the opportunity to extend the guard period
and increase chick survival. However, to extend the guard stage
successfully, they must provide larger meals and maintain higher chick
growth rates, even if just one parent at a time is foraging, which
previous work has shown is not possible for all individuals. We show that
the factors governing trade-offs in chick-rearing behavior of Adélie
Penguin parents may vary in accord with environmental conditions, a result
from which we can better understand species’ adaptations to environmental
changes.