Penguin population declines are found to occur in hotter years
Wednesday 3 August 2016 11.00 BSTLast modified on Wednesday 3 August 201611.02 BST
We know the world is warming, and we know humans are the main reason. But so what? The thing we’d really like to know is, what will the impacts be on our planet, its biodiversity, our society, our economies? It is only through understanding the impacts of climate change that action for reducing greenhouse gases can be motivated.
This is one of the reasons I was so interested in a very recent study from the University of Delaware, which addressed how penguins will fare in a warming world. The article was published in Scientific Reports and is available open access so anyone with an internet connection can read it here.
Lead author Megan Cimino and her colleagues looked at Adelie penguin populations and asked whether their years of increasing or decreasing population corresponded to warm, cold, or normal temperatures. In the Antarctic, which is where these penguins live, the situation is a bit complex because the land area is large and weather/climate changes are not consistent across the region.
For instance, large parts of the Western Antarctic Peninsula (WAP) are warming quite rapidly, amongst the most rapid in the world. On the other hand, in the East, some areas are warming just a little while others are cooling slightly. Since Adelie penguins live on the periphery of the ice sheet, they are exposed to a wide range of Antarctic climate regions.
The authors found that penguin colony declines occur preferentially in years where the sea waters are warmer than average. This is in contrast to colonies whose populations are stable or increasing – those occur in normal or cooler waters. This finding was particularly striking when Adelie penguin populations in the WAP (which is warming) were compared with populations elsewhere in the continent.