the plight of the penguins
Antarctic biodiversity has not escaped the environmental stress anthropogenic-induced warming is causing globally. Penguins, birds that have evolved to perfectly suit their harsh environment, are now increasingly at risk as population numbers decline in the fact of climate change. Factors impacting their ability to adapt to rapid warming include long-life spans and their slow microevolution: instead of adapting, penguin species tend to migrate or disperse. This trend has seen emperor and Adélie penguins contracting poleward, whilst
Multiple stressors face penguin populations. Whilst climate change rightly garners the most attention as the main risk facing the birds, concerns also exist regarding the impact of eco-tourists on penguin wellbeing. Emperors, for example, will change paths to avoid contact with tourists and will sometimes walk or stand still in the presence of humans over tobogganing: both observations require emperors to expend more energy. Tourist impact on penguin health is definitely an area that needs further study as tourist figures to the continent sky-rocket.
As mentioned, the key stressor affecting penguin populations is rising temperatures. Limited in the depths and ranges they can forage for food, the birds are ‘highly sensitive to climate change’. This sensitivity is predominantly down to their staple food source (krill) declining as oceanographic conditions are altered. As oceans warm (in this context, the Southern Ocean in particular), reproductive grounds for penguin food sources like krill are under-stress, in turn affecting the health of populations. Species like the chinstrap are increasingly at risk to declining krill populations: breeding almost only in the Scotia Sea (where krill decline is recorded), when combined with other stresses like sea-ice decrease, changes to the chinstrap’s main food source could prove disastrous.
The other key stressor affecting penguin species is sea-ice decline and sea-surface temperature increase due to climate change. Loss of sea-ice habitats where penguins breed is a major risk. Emperors, in particular, seem to be struggling with a decline in winter sea-ice. This is partly due to the fact that emperors need pack-ice to
It’s clear multiple factors are increasing penguin sensitivity to climate change. Given that it’s not only ice-loving penguins (like chinstraps) or ice-avoiding penguins (like Adeliés) declining, sea-ice decline alone isn’t a sufficient explanation. Change in prey-abundance is an equally (or more) important stressor.
With these concerns combined, fears of king penguin populations declining by 70% in the near future aren’t surprising. Neither are calls for the status of penguins to be reviewed by the International Union for the Conservation of Nature.
Beyond halting climate warming, the most the scientific community can do is keep a close eye on population figures. Future tracking and remote-sensing technology will aid this venture and our understanding of how birds as unique and hardy as penguins will cope in the face of climate change.
Cover photo by Cassie Matias on futuretravel.today