Harris' Fundación Patagonia Natural has expressed concern to regional governments about anchovy fisheries.
The organization is also participating in a Wildlife Conservation Society study that documents the toll of overfishing on the southwest Atlantic ecosystem.
Harris is hopeful the efforts will result in measures that maintain a steady supply of fish for the penguins. But he says he and his colleagues face many challenges.
"The fishing industry is very powerful," he said. "It generates a lot of money, provides a lot of jobs, [and] has the backing of the Argentine government."
Harris and his colleagues have successfully stood up to past challenges. Their efforts over the past two decades led to greater enforcement of shipping regulations and redrawn shipping lanes near Argentina's penguin colonies.
This resulted in less oily water being illegally dumped near the colonies.
Ships fill their empty oil tanks with water to weigh them down and maintain balance at sea, then dump the water before arriving at port to fill up with petroleum, Harris explained.
The dumped water has an oily residue that destroys the insulating properties of penguin feathers.
In an effort to stay warm, the penguins head toward shore, where they eventually starve to death. And ingestion of even a small amount of oil, usually through the preening of feathers, can cause stomach lesions and depress the immune system.
"The number of oiled birds that we see on the shores of Patagonia has declined enormously since the 1980s," Harris said.
But Boersma said the picture is not as rosy elsewhere. Early next year, she plans to publish results from a survey of oiled birds off Uruguay and southern Brazil.
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