Climate 'presses' and 'pulses' impact Magellanic penguins—a marine predator—with guidance for conservationists
Climate change will reshape ecosystems worldwide through two types of climate events: short-term, extreme events—like a heat wave—and long-term changes, like a shift in ocean currents. Ecologists call the short-term events ...
Presses and pulses will likely have different effects on animal species. But how? And how will animals respond? Answering these questions is no easy feat because individual events can have dramatically divergent impacts on an animal species. Yet understanding the effects of presses and pulses is essential as conservationists and policymakers try to preserve ecosystems and safeguard biodiversity.
Researchers at the University of Washington have discovered how different presses and pulses impacted Magellanic penguins—a migratory marine predator—over nearly four decades at their historically largest breeding site in Punta Tombo, Argentina. In a paper published the week of Jan. 9 in the Proceedings of the National Academy of Sciences, the team from the UW's Center for Ecosystem Sentinels reports that, though individual presses and pulses impacted penguins in a variety of ways, both were equally important for the future survival of the penguin population. They also found that these types of climate changes, taken together, are leading to an overall population decline at this particular site.
"We found that penguin survival doesn't rest solely—or even largely—on one or a few climate effects," said lead author T.J. Clark-Wolf, a UW postdoctoral researcher in biology and center scientist. "Instead, many different presses and pulses impact penguin reproduction and survival over time."
The study analyzed data collected at Punta Tombo from 1982 to 2019 by co-author Dee Boersma, founder of the Center for Ecosystem Sentinels and a UW professor of biology, and collaborators. The data include:
survival and reproductive success for nearly 54,000 penguins at the site, which historically is where hundreds of thousands of Magellanic penguins have come to breed each summer
Rain soaks the down plumage of a Magellanic chick, left, that is still too young to have the waterproof plumage of its parent, right. Credit: Dee Boersma/UW Center for Ecosystem Sentinels
University of Washington doctoral student Katie Holt examines adult Magellanic penguin corpses (circled) at Punta Tombo, just after a heat wave on Jan. 19, 2019, killed at least 354 penguins. Temperatures that day spiked to 111.2 F in the shade. Credit: Anna Sulc/University of Washington
A 2002 satellite view of the Río de la Plata, which forms at the confluence of the Paraná and Uruguay rivers and expels a plume of silt that impacts winter feeding conditions for Magellanic penguins. Credit: Jacques Descloitres/MODISRapid Response Team/NASA/GSFC