Dee Boersma on penguins as ocean sentinels

Boersma said penguins can’t find food as easily because of the effects of warm water on the fish they eat. Warming ocean temperatures, she said, have altered sex ratios in some populations of the fish they eat, creating more males.

Dee Boersma: Variation in the ocean world affects penguins – that’s why we think of them as sentinels, telling us something about the ocean environment.

Dee Boersma is director of the Wildlife Conservation Society’s Magellanic Penguin Project and winner of a 2009 Heinz Award for her conservation work. She’s been studying the penguin population at Punta Tombo, Argentina for nearly 30 years.

Dee Boersma: The reason Punta Tombo is so special is because there are around 200,000 breeding pairs there. That makes it the largest breeding colony for Magellanic penguins in the world.

Dr. Boersma said the challenges faced by penguins show the cascading effect of climate change on ecosystems. She gave one example:

Dee Boersma: These penguins are having to go 40 miles further to find food than a decade ago. And so, while one bird is swimming further to find food, the other is sitting on the nest, keeping the egg warm, and losing weight.

Boersma said penguins can’t find food as easily because of the effects of warm water on the fish they eat. Warming ocean temperatures, she said, have altered sex ratios in some populations of the fish they eat, creating more males.

Dee Boersma: And so of course, if there aren’t females, there’s not as many eggs that are laid, and so you can get a really dramatic decrease in population. And for penguins, that means not as much food.

Dee Boersma: It’s only really by looking at a system for a long period of time can we get a sense of how the system works, what’s happening to it, and what are the impacts that humans are also having on that system.

Boersma said the Penguin Project at Punta Tombo, Argentina, began in 1982. She described Punta Tombo as a desert environment. The penguins live and breed in burrows, or near scrubby bushes.

Dee Boersma: They spend the winter in northern Argentina or off the coast of Brazil, and now they’re headed back to Argentina. We’re there with the penguins until most of them leave at end of March.

Boersma said that the penguins at Punta Tombo face additional pressures, because they share more of the human world. The colony gets about 100,000 visitors a year, she said.

Dee Boersma: This is a real challenge. How do you allow that many people to see penguins? The good news is, penguins are really tolerant. The bad news is, more and more people are coming to see the penguins, and many of them don’t really that much care about penguins.

She said a potential danger of this ecotourism is that tourists could disrupt the penguin’s activities and behaviors. If the penguins can’t access sea or shade, they might overheat and die in the hot summers. However, Boersma said that there have been many improvements in the way that the area manages tourism.

Lindsay Patterson