Journal of Ethology 22, 91-98.
Inter-colony and sex differences in the effects of parental body condition and foraging effort on the brood growth of Adelie penguins.
Watanuki Y, Takahashi A, Sato K, Kato A, Bost CA. 2004
Among colonies with different foraging distances,
central-place-foraging seabirds may change their foraging
and reproductive efforts. We compared the body condition,
meal frequency, and diving behavior of male and female
Adelie penguins at two locations: Dumont dfUrville, where
there was little sea ice and they foraged in open waters far
from the colony; and Syowa, where there was heavy, fast
sea ice and they foraged in ice cracks close to the colony.
The parental mass decrease rate during the chick-rearing
period was similar between colonies and between sexes.
A large individual variation in meal frequency positively
affected the brood growth rate, but daily underwater time
did not. A weak but significant positive effect of body condition
on brood growth rate was found only in males at
Syowa. It was suggested that males work with better body
condition than females. We propose the hypothesis that the
regional difference in the distance to the feeding sites and
the sex difference in body energy reserve might constrain
the capacity to regulate reproductive effort.
PG04-06
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