Emperor penguins are indicator species whose population trends can illustrate the consequences of climate changes. The proposal was rooted in foundational research and findings that scientists provided to USFWS, including a study in Global Change Biology, also publishing today, recommending that emperor penguins be listed as threatened under the Endangered Species Act. The Center for Biological Diversity has long fought for Endangered Species Act protection for the emperor penguin. Endangered Species Act. In July 2019, the Center sued the Trump administration for failing to act on the petition to protect emperor penguins under the Act.