The Earth’s changing climate has increased the frequency of extreme weather events around the world, such as droughts, storms, abnormally high or low temperatures and wildfires, which have led to the decline of many flora and fauna species, including the Magellanic penguin.
A recent study, published in the online journal PLOSone, followed 3,496 Magellanic penguin chicks in Punta Tombo, Argentina, between 1983 and 2010. In this area, there has been an increase in the frequency of extreme weather events, which were found to be increasing the mortality rate of young Magellanic penguins. Professor Dee Boersma, who led the research, said, “It’s the first long-term study to show climate change having a major impact on chick survival and reproductive success.”
Extreme weather patterns can cause mortality, as the chicks can contract hypothermia. When Magellanic penguins are young their down is not waterproof, and if it gets wet an individual cannot control its body temperature. At times when temperatures are much higher than usual, some chicks may contract hyperthermia, which is also fatal. Indirectly, climate change is increasing chick mortality through starvation, as altered fish behaviour decreases hunting success for the adult penguins, which are then unable to feed their chicks.
It is estimated that the negative effects of global warming were responsible for around 7% of Magellanic penguin chick mortalities over the period of the study, while 40% were due to starvation. The authors of the report, Professors Dee Boersma and Ginger Rebstock said, “Climate variability in the form of increased rainfall and temperature extremes, however, has increased in the last 50 years and kills many chicks in some years.”
The study also found that adults start laying their eggs three days later than previously recorded, which decreases the amount of time the young have to develop before the main storm season begins in November. Professor Ginger Rebstock said, “We’re going to see years where almost no chicks survive if climate change makes storms bigger and more frequent during vulnerable times of the breeding season, as climatologists predict.”
As well as climate change, it is also thought that several other factors have contributed to the decline of the Magellanic penguin, including oil spills, water pollution, reduced prey availability from overfishing, being caught as bycatch and disturbance from tourists.
The study also suggests that the negative effects of climate change in the region were affecting other Argentinean species. Populations of other penguin species around the world, such as the Adélie penguin, are also in decline due to decreasing sea-ice and other issues relating to altered weather patterns.
Read more about this story BBC News – Climate change is ‘killing Argentina’s Magellanic penguin chicks’
Read the journal at PLOSone – Climate Change Increases Reproductive Failure in Magellanic Penguins
Read more about the penguin conservation project at the Zoological Society of London
Hannah Mulvany, ARKive Content and Outreach Officer