Landfast ice: a major driver of reproductive success in a polar seabird

In a fast-changing world, polar ecosystems are threatened by climate
variability. Understanding the roles of fine-scale processes, and linear
and nonlinear effects of climate factors on the demography of polar
species is crucial for anticipating the future state of these fragile
ecosystems. While the effects of sea ice on polar marine top predators are
increasingly being studied, little is known about the impacts of landfast
ice (LFI) on this species community. Based on a unique 39-year time series
of satellite imagery and in situ meteorological conditions and on the
world's longest dataset of emperor penguin ( Aptenodytes forsteri )
breeding parameters, we studied the effects of fine-scale variability of
LFI and weather conditions on this species' reproductive success. We
found that longer distances to the LFI edge (i.e. foraging areas)
negatively affected the overall breeding success but also the fledging
success. Climate window analyses suggested that chick mortality was
particularly sensitive to LFI variability between August and November.
Snowfall in May also affected hatching success. Given the sensitivity of
LFI to storms and changes in wind direction, important future
repercussions on the breeding habitat of emperor penguins are to be
expected in the context of climate change.