Sampling distribution.

<p>Sampling was restricted to the periphery of the colony. Orange zone boundaries are marked on the ground for remote parameter assessment. Shaded clusters run from C1 (north-west) to C6 (south-east). Orange zone: extent of the colony at the peak of the breeding season.</p

Microsatellite analysis: multiplexing parameters and summary statistics.

<p>Microsatellite analysis: multiplexing parameters and summary statistics.</p

Individual inbreeding and nearest-neighbours-relatedness tend to have a clustered distribution throughout the colony.

<p>(A) Distribution of Ritland’s individual inbreeding coefficient along the sampling area. Shaded zones represent analysis clusters C1 to C6. Gray circles signal point displacement for representation purposes. (B) 2D-LSA scores (9 neighbours analysis). Red triangles represent individuals that are significantly more related to their 9 nearest neighbours than to random individuals.</p

Ecological descriptors of breeding-site quality exhibit a strongly heterogeneous distribution across the colony.

<p>(A) Adult tick load, averaged for years 2005–2012. Contour lines: 0.02 steps. (B) 8-neighbour chick survival, averaged for years 2010–2012. Contour lines: 0.1 steps. (C) Site occupancy chronology, averaged for years 2006–2013. Ratio of brooding birds amongst 50 randomly selected breeders. Contour lines: 0.1 steps.</p

First axis of principal component analysis as a summary habitat-quality index.

<p>White polygons: clusters C1 to C6.</p

Observed individual inbreeding distribution deviates from expected distribution in a non-related sample.

<p>(A) Difference between simulated and observed mean population inbreeding level (Ritland’s coefficient) for 50 simulated datasets. Solid red line: observed difference. Gray intervals: 1%, 5% and 10% confidence intervals. (B) Observed distribution in the sample. (C) Expected distribution in a non-related population, given the same parameters as the observed population.</p

2012 census of the Mertz emperor penguin colonies.

a<p>Breeding pairs were obtained by applying a pair-to-chick ratio of <i>ca.</i> 1.28 obtained from the emperor penguin colony at Pointe Géologie, Adélie Land.</p

Satellite images of the Mertz Glacier.

<p>Circle area is proportional to colony size. Continent is on top, open sea at the bottom. <b>A.</b> Estimated location of the Mertz emperor penguin colony on November 13^th, 2009 (red circle) on the eastern flank of the Glacier tongue. A large crack in the Mertz Glacier is visible (red arrow). The green circle corresponds to Pointe Géologie colony. <b>B.</b> Location of the two new colonies of emperor penguins on December 3^rd, 2012 (blue circles), 2 years after the 2010 calving of the Glacier tongue. The berg (overall length of 80 km and a width of 40 km) broke off the Mertz Glacier after being rammed by another iceberg. The green circle corresponds to Pointe Géologie colony. Images downloaded from the USGS website (<a href="https://lta.cr.usgs.gov" target="_blank">https://lta.cr.usgs.gov</a>).</p

Western emperor penguin colony.

<p>Aerial view of the western emperor penguin colony (67°14′S, 145°30′E) showing adults and chicks present on November 2^nd, 2012. Photograph by Robin Cristofari, from an altitude of <i>ca.</i> 1,000 feet.</p