To Dee Boersma, penguins are more than charming birds in tuxes. Highly sensitive to variations in the ocean, penguins are sentinels, sounding the alarm on environmental threats to marine ecosystems. As director of the Wildlife Conservation Society's Penguin Project, she has dedicated almost three decades to tracking them in the South Atlantic. Using "nametags" -- numbered metal bands -- Boersma and her team follow hundreds of individual penguins to learn where they go, what they eat and how they survive to the next breeding season.
Boersma's studies show that the birds must now swim further in search of food, costing energy and time, leading to detrimental consequences for their mate and young. Her data does not paint a pretty picture, but local conservation efforts she spearheaded, such as moving oil tanker lanes further from the coast, have been successful. Humans, she notes, are responsible for penguins' current woes but can also be their saviors.