Penguins living along the Patagonian coast of Argentina can serve as living monitors of their environment by using small, chemical-detecting leg bands, according to a study from the University of California, Davis, and the State University of New York at Buffalo. For the proof-of-concept study, published in the journal Earth: Environmental Sustainability, UC Davis scientists outfitted 54 Magellanic penguins with silicone passive samplers placed gently around their legs for a few days during the 2022-24 breeding seasons. The sensors safely absorbed chemicals from the water, air, and surfaces the penguins encountered while the unwitting "toxicologists" foraged to feed their chicks.