Penguins in Trouble Worldwide (NY Times)greenspun.com : LUSENET : Grassroots Information Coordination Center (GICC) : One Thread
Headline: Penguins in Trouble Worldwide
Source: New York Times, 26 June 2001
Harry's habits were as predictable as clockwork, so when he did not return from his last ocean voyage as expected, Dr. Dee Boersma knew something was wrong.
"We had signals until Dec. 6," said Dr. Boersma, a penguin researcher at the University of Washington who encountered Harry — a penguin outfitted with his own satellite transmitter — at a nesting area at Punta Tombo, Argentina. Harry headed out to forage at sea while his mate took her turn on their eggs, Dr. Boersma related. "Then we never heard from him again. We looked for him to come back every day. We just don't have adult birds disappear like that."
But late last year and early this year, the summer breeding season in the Southern Hemisphere, Magellanic penguins like Harry did disappear at sea. Thousands more washed up dead on the beaches north of Punta Tombo. Many birds abandoned their nests, leaving chicks to starve. Among the survivors, many were in bad shape, having difficulty finding the fish they needed to sustain themselves.
"This is the worst year ever," said Dr. Boersma, whose studies of the colony over 18 years have been supported by the Wildlife Conservation Society. "And we keep getting a lot of bad years."
Researchers say the Magellanic penguins at Punta Tombo, which have steadily decreased in number for more than a decade, are not alone. Around the world, many penguin populations are declining, researchers say, and evidence is mounting that global warming, whether natural or human-induced, is a prime cause.
Unless things change, they say, the outlook for some of these penguin species will be grim. Ten of the world's 17 penguin species are already listed as threatened or endangered.
Though a few species are thriving, "penguins, in general, are experiencing some really serious problems," said Dr. Lloyd Davis, penguin biologist at the University of Otago in New Zealand. "They are in trouble."
In addition to climate change, Dr. Davis said problems like overfishing and oil spills threatened these flightless birds. Penguins' best hope for overcoming these many obstacles, scientists say, may be their abundant adorability and the protection and money it can bring.
One typically thinks of penguins as waddling about atop miles of featureless ice, but many of the penguins at greatest risk are those species that have strayed farthest from the South Pole.
The endangered Galápagos penguin, a tropical species, is also one of the rarest. Found only on the Galápagos islands off Ecuador, these birds have been hard hit by rising temperatures. Dr. Boersma and others studying the penguins have found that the warmer the waters, the more the birds struggle to find food and to breed. In the warmest years, birds can fail to breed altogether and large numbers of adults can die of starvation.
Two other South American penguin species, the Magellanic and Humboldt, also suffer as waters warm. Since 1987, the number of Magellanic penguins at Punta Tombo has declined by 30 percent. It remains the world's largest colony of the species, still numbering in the hundreds of thousands, but, as with other penguins, the downward trend has researchers worried.
"If we get a series of intense El Niños, they're going to disappear," Dr. Patricia Majluf, conservation biologist at Wildlife Conservation Society, said of the colony of Humboldt penguins she studies, whose numbers are also dropping. "We lost half during one bad El Niño and these are very slow breeding birds."
El Niño is a phenomenon that comes and goes every few years in which the waters of the eastern tropical Pacific warm up, a change that can drive fish and other penguin prey far from colonies. The result, scientists find, can range from decreased egg sizes or deaths of chicks to, in a few cases, large-scale deaths of adults.
In cooler La Niña years, colonies can begin to recoup their losses. But in recent decades, the number and intensity of El Niños has increased while La Niñas have declined.
As for Harry and the other dead or missing penguins, researchers now suspect that they succumbed to a biological toxin like a red tide and again, scientists say the evidence points to climate change as the culprit. Such toxic blooms are associated with warming ocean waters.
Dr. Boersma said she got her first inkling that biological toxins might be at work when a freshly dead penguin floated ashore this winter. "It had an empty stomach that looked like it had been washed with acid," she said, adding that otherwise it seemed well fed and healthy. "He looked fine, except that he was dead."
Other die-offs, also suspected to have been caused by biological toxins, have hit penguins elsewhere. "In 1990, over half the known yellow-eyed penguins died from some mysterious disease," said John Darby, seabird conservationist, now retired from the University of Otago, who has studied these endangered penguins in New Zealand for 22 years. "It was quite extraordinary. They were just dying all over the place, at their nests, on the beaches."
These penguins also looked healthy; Mr. Darby said he and colleagues believed that a biological toxin killed them as well.
Yellow-eyed penguins are unusual in that they require forest for nesting, putting them in proximity to New Zealanders who have logged to make way for farming. In other areas, penguins must compete with growing fishing industries. Oil spills have killed off many penguins and in Peru the endangered Humboldt is at additional risk because it is considered a good meal by people near the colonies.
Even the penguins in remote Antarctica, which tend to be doing better in terms of absolute numbers, can suffer declines when the bitterly cold seas warm.
Dr. Christophe Barbraud and Dr. Henri Weimerskirch, from the National Center for Scientific Research in France, reported in the journal Nature last month that warming seas and a decline in sea ice were linked to a 50 percent drop in numbers in a well-studied population of emperor penguins over the last 50 years.
In what may be the best understood of penguin declines, Dr. Wayne Trivelpiece, director of seabird research for the United States Antarctic Marine Living Resources program, and colleagues have studied Adelie penguins.
What researchers have discovered is that as the seas have warmed in recent decades, the annual formation of winter sea ice no longer reliably extends to its usual reaches north of the South Shetland Islands. Instead, since the middle of the 1970's, this pack ice formed in that region only two years out of every six to eight years.
The pack ice contains a store of frozen diatoms, a critical food source for young crustaceans known as krill, which are the only food of Adelie penguins. Without pack ice in their spawning grounds, the entire generation of new krill dies and the only krill alive are those that survived from the last winter when there was pack ice.
With the pack ice forming less frequently, the krill have declined and penguin numbers have experienced sometimes sharp drops.
But Dr. Trivelpiece said the real problem was that ice had not formed in the krill spawning grounds now for six winters — about as long as most krill can live. Dr. Trivelpiece said that without a winter's ice soon, the last of the aging krill might never have the chance to reproduce before they expired, crashing the krill population and threatening even healthy populations of Adelies now living at the bottom of the world.
"We're really out on the wire right now," Dr. Trivelpiece said. "If we don't get ice this winter or next, the whole house of cards will come down."
But penguins do have a formidable weapon: their extreme cuteness. Money to protect them has flowed in from tourists as well as wealthy benefactors who want to help these tuxedoed charmers.
Mr. Darby said yellow-eyed penguins had been adopted as mascots of a New Zealand cheese made by Mainland Products Ltd., whose commercials had long featured an elderly fellow who walked with a bit of a waddle. He said the addition of a waddling yellow-eyed penguin to the ads had been a huge success; over the years the company has provided more than a million dollars for work to protect the species.
In other places, penguins are tourist attractions, providing public relations protection and fund-raising for the birds. At Punta Tombo, each year 50,000 tourists, mostly Argentines, come to see what Dr. Boersma calls the "penguin megatropolis" of thousands and thousands of Magellanic penguins.
This black and white spectacle of birds — known as jackass penguins because of their braying call — has become so beloved that researchers say proposals in the 1980's to harvest the penguin skins to make gloves would never be considered today.
In Australia, a daily "penguin parade" of what can be hundreds or thousands of birds known as little penguins regularly draws paying tourists providing a source of income that has financed much research on managing the population. Tourists gather to watch the masses of petite penguins toddle out each morning to forage at sea and then return each evening to march back to their burrows.
"These are the most fantastic natural history spectacles," Dr. Boersma said. "I haven't met a person yet who didn't love penguins."
-- Andre Weltman (email@example.com), June 26, 2001