- The Washington Times - Thursday, December 7, 2006

People just can’t seem to get enough of penguins. With the 2005 release of the documentary film “March of the Penguins,” interest in the black and white birds has grown. This holiday season, “Happy Feet,” an animated feature film about penguins, also is in theaters.

Penguins are a mascot for biology in the Antarctic, says Roberta Marinelli, director of the Antarctic Biology Program at the National Science Foundation in Arlington. She holds a doctorate in marine science.

“If you are thinking about the entire Southern Ocean ecosystem, penguins are top predators,” Ms. Marinelli says. “You can learn about the ecosystem when you see how penguins interact in the food web.”

The Academy Award-winning “March of the Penguins” will air Monday on the Hallmark Channel. The movie documents the annual migration of emperor penguins.

In April, the beginning of winter in the Antarctic, emperor penguins travel from the pack ice out at sea to the colony site for courtship and breeding, says Dr. Paul Ponganis, a research physiologist at Scripps Institution of Oceanography in La Jolla, Calif. He is a grantee of the National Science Foundation in Arlington. He usually travels to McMurdo Station on Ross Island in the Antarctic once a year for research.

The trip is estimated to be hundreds of kilometers, he says, and researchers are unsure how the penguins find their way.

By early June, the female lays an egg, he says. The female penguin transfers the egg to the male, which will incubate the egg for 60 to 65 days, while fasting. Females usually weigh about 65 pounds, while males are about 25 pounds heavier. Because the females are smaller, they can’t fast as long as the males, so once the eggs are laid, the females must return to the sea to eat, he says. When the female returns, the chick hatches.

“The timing is important,” Dr. Ponganis says. “They will exchange the chick, and the male will go out to sea to feed. The female comes back with a stomach full of food to regurgitate to the chick.”

The parents take turns providing for their young with the father feeding the chick while mom returns to the sea for food. Come December, the chick weighs about 25 pounds. By the middle of December the adults leave and the chicks find their own way to the sea, returning to the colony by age 5.

For two to three weeks in January, the adult emperor penguins molt and grow new feathers. Because they lose their insulation, they can’t go in the ocean for food during the process, Dr. Ponganis says. Once they finish molting, they start eating and make their way back to the colony for courtship.

Scientists believe about a half million emperor penguins breed in 40 colonies in Antarctica, he says. The Ross Sea region has seven colonies with one-third of the birds.

“During the Antarctic winter, there aren’t any animals that stay on the surface of the southern latitude in the cold other than emperor penguins,” Dr. Ponganis says. “The males huddle together to stay warm when they are holding the egg on top of their feet.”

Emperor penguins are unique because they breed in Antarctic winter under exceedingly harsh conditions, says Wendy Turner, curator of birds at SeaWorld San Diego in California.

The San Diego SeaWorld is the only place in North America with emperor penguins, she says. The birds live in a replicated Antarctic environment, along with Adelie, gentoo, macaroni and king penguins.

In the 1980s, emperor penguins were brought to SeaWorld and settled into an environment similar to the Antarctic. Snow is blown daily and Antarctic light cycles are artificially reproduced. Over the years, 16 chicks hatched at the site. The current emperor penguin population at SeaWorld is 36.

“The chicks are the cutest things in the universe,” Ms. Turner says. “The down that makes them fluffy is so thick and soft. They are just cute, very, very cute, black and white, and fluffy and cute. They are something so very special.”

Continued climate warming could endanger any of the 17 species of penguins worldwide, says Bill Fraser, president of the Polar Ocean Research Group in Sheridan, Mont. He holds a doctorate in wildlife ecology. He usually travels once or twice a year to Palmer Station on the Western Antarctic Peninsula, near the southern tip of South America, where he has worked for the past 30 years.

Winter temperatures in the Western Antarctic Peninsula have increased by 6 degrees Celsius in the last 50 years, which has led to the almost complete disappearance of sea ice that forms during the wintertime, he says. As a result, the population of Adelie penguins has decreased by 70 percent in the Palmer Station region in the last 30 years.

“Adelie penguins depend on winter sea ice as a foraging platform,” Mr. Fraser says. “They can’t access prey very well without sea ice being present.”

As a result, gentoo and chinstrap penguins, subpolar species, have invaded what used to be a polar environment in the Palmer Station region, he says.

The primary range for gentoo and chinstrap penguins is to the north of Palmer Station. As temperatures have warmed in the Palmer Station region, the two ice-avoiding species have migrated from the north, he says.

While the population of chinstrap penguins has increased by about 300 percent and the number of gentoo penguins has increased by about 4,000 percent, Adelie penguins are going extinct in the area, he says.

The Adelie population isn’t the only one in the region that has been adversely affected. In the 1950s, there was a population of emperor penguins about 250 miles to the south of the Palmer Station region with about 350 breeding pairs, he says. When the population was surveyed in 2001, there were only nine pairs left.

“I would expect now that the population is extinct,” Mr. Fraser says. “There would be a very low probability that there are any coming back.”

The climate warming in the West Antarctic Peninsula also has led to a large decline in krill in the Scotia Sea, which has caused a substantial decline in Adelie and chinstrap young penguins being able to survive into adulthood, says Wayne Trivelpiece, a wildlife biologist at the Antarctic Ecosystem Research Division of the Southwest Fisheries Science Center in La Jolla, Calif. He has a doctorate in behavioral ecology and zoology.

In the future, fisheries taking too much krill from the area could worsen the problem, he says.

“We are using penguins as a poster child for other animals that depend on krill,” Mr. Trivelpiece says. “They are an indicator species. As go the penguins, so would go the whales, the seals and other squid and fish. A lot of other animals rely on the kril species.”

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