Imagine you live in the suburbs of Chicago and you must commute hundreds of miles to a job in Iowa just to put food on the table. Magellanic penguins living on the Atlantic coast of Argentina face a similar scenario, and it is taking a toll.
The penguins' survival is being challenged by wide variability in conditions and food availability, said Dee Boersma, a University of Washington biology professor and a leading authority on Magellanic penguins.
For example, while one parent incubates eggs on the nest the other must go off to find food. But these days, Boersma said, penguins often must swim 25 miles farther to find food than they did just a decade ago.
"That distance might not sound like much, but they also have to swim another 25 miles back, and they are swimming that extra 50 miles while their mates are back at the breeding grounds, sitting on a nest and starving," she said.
Boersma has recently published research documenting some of the serious challenges faced by Magellanic penguins in a colony at Punta Tombo, Argentina, that she has studied for more than 25 years. She discusses her research Thursday (Feb. 12) during a news briefing and Friday during a symposium at the American Association for the Advancement of Science meeting in Chicago.
The Punta Tombo colony has declined more than 20 percent in the last 22 years, leaving just 200,000 breeding pairs, Boersma said.
There are several reasons for the decline, including oil pollution and overharvesting of fish by humans. Climate variation also is a major problem, she found.
Longer trips for food during a given breeding season lessen the chances that a given penguin pair will successfully reproduce. Some younger penguins move to colonies that are closer to food one year but might be farther away from food the following year. Increased ocean variability means penguins often return to their breeding grounds later and are in poorer condition to breed.
They also are increasingly subject to having their desert nests flooded by rain. Five times in the last 25 years, Boersma said, the Punta Tombo reserve has recorded about 2.5 inches of rain between Oct. 15 and Dec. 16, which threatens the survival of eggs and small chicks.
"That turns their little nests into swimming pools," she said.
In addition, there have been increasing instances of El Niño-like events that alter ocean currents, forcing penguins to travel farther for the fish on which they feed. Increasingly, Boersma has found that penguins she tagged at Punta Tombo years ago are turning up in colonies as much as 250 miles farther north. Birds migrating in search of food are forming the new colonies, but often they end up on land that is not part of a government preserve like Punta Tombo is.
The problems don't just confront Magellanic penguins, said Boersma, director of the Wildlife Conservation Society's Penguin Project. Of 17 penguin species, 12 are experiencing rapid population declines. The least concern is for the emperor, king, Adélie, little blue and chinstrap penguins, she said. All the rest are nearly threatened, threatened or endangered.
She noted that the success of Argentine fishing fleets is a good signal for how the Magellanic penguins will fare in a given winter as they store nutrition to prepare for the breeding season. There is a small anchovy fishery in the winter, and penguins also favor anchovies. But when the boats don't do well catching anchovies in the winter, that is bad news for penguins in the following breeding season.
"They do well when the fishermen are catching anchovies. If the fishermen are not successful, the penguins start to falter," Boersma said. "If the fishery expands and then collapses, as most do, the penguins will be in trouble.
"Penguins are having trouble with food on their wintering grounds and if that happens they're not going to come back to their breeding grounds," she said. "If we continue to fish down the food chain and take smaller and smaller fish like anchovies, there won't be anything left for penguins and other wildlife that depend on these small fish for food."
For more information, contact Boersma at 206-616-2185, 206-616-4054 or firstname.lastname@example.org
Vince Stricherz | Newswise Science News
Scientists team up on study to save endangered African penguins
16.11.2017 | Florida Atlantic University
Climate change: Urban trees are growing faster worldwide
13.11.2017 | Technische Universität München
The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.
Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...
Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.
That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...
Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.
During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....
The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.
Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...
Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...
15.11.2017 | Event News
15.11.2017 | Event News
30.10.2017 | Event News
17.11.2017 | Physics and Astronomy
17.11.2017 | Health and Medicine
17.11.2017 | Studies and Analyses