Post-settlement faunal extinction rates are widely cited statistics and help to understand the magnitude of recent biodiversity loss driven by human activity. However, extinction rate estimates can vary greatly depending on factors such as the geographic boundaries of the region being considered, how the faunal group is defined, completeness of fossil records, and taxonomic frameworks.
The population dynamics of the Cape Royds rookery were modelled by computer, in order to determine the probable causes of the dramatic increase since 1980 in the numbers of Adelie penguins, Pygoscelis adeliae, breeding in the Ross Sea region, Antarctica. Variations in the extent of sea-ice around the rookery during incubation and chick rearing cannot feasibly explain the population increase and another factor or event must be introduced, which increases chick production per breeding pair and decreases adult mortality.
