Changing weather patterns, worsened by climate change, could be a major factor, since this can push wild fish and squid farther away from where these penguins can forage. (This happened in the late 1990s when weather caused by the El Niño weather pattern was particularly bad. "This resulted in population decline and poor breeding success," Weimerskirch said.)
Earlier this year, another study showed that worsening weather patterns, caused by human activity, could push king penguins to extinction in our lifetime. "Our work shows that almost 70 percent of king penguins — about 1.1 million breeding pairs — will have to relocate or disappear before the end of the century because of greenhouse gas emissions," Céline Le Bohec, a researcher with the French National Center for Scientific Research (CNRS) and the University of Strasbourg, told the BBC in February.