Pay the chinstrap Penguin and Adélie penguins in the Antarctic Peninsula region are in the last 30 years, especially of dramatic decline in the supply of tiny, shrimp-like krill, their main prey, fell by more than 50 per cent, says a new study.
Krill, now to 40 to 80 percent have, in due course in the first place fast w?rmentemperaturen in the pane-South Shetland Islands in the vicinity of the Antarctic Peninsula and close to declined sites.
This is one of the fastest warming places on the planet with average winter temperatures some 10 degrees Fahrenheit warmer now than in pre-industrial times.
Researchers previously thought that chinstrap Penguin heated penguins as temperature, because the open water in the vicinity of ice edges, unlike Adélie penguins, which on ice winter winter would thrive. In previous years Chin straps have better in warmer winters, while Adelie penguins their number grew in cold winters with lots of ice.
But since about 1980, both types of penguins are drastically declined, and now researchers believe that they can point to plummeting populations of krill.
Researchers report in a paper published today in the National Academy of Sciences long-term monitoring of krill and Penguin in the South Shetland Islands and data from other sites throughout the Scotia sea, and the West Antarctic Peninsula, the northernmost finger of the Antarctic continent.
"The way really know this story learned we saw the huge changes in the penguin populations and went looking for reasons, why,", said study author lead Wayne Trivelpiece, by the National Oceanic and atmospheric Association's national marine fisheries service in La JollaCalif.
The team saw the data, which they had accumulated over the years and noticed that during penguins, used to a wide spread of krill sizes, in the last few decades, were eating similar size in a given year the krill, as growing up a cohort of the krill but and creatures were eaten, but older and younger krill were missing.
"We went back and looked at and saw that populations were years with large krill summers, winters with much ice was followed, environmental data", Trivelpiece said. "The ice was suddenly disappear." "I was not as extensive form."
Phytoplankton is growing in mats at the bottom of the sea ice for food at critical stages of krill depends on, he said.
He said "The young krill, which are produced in the Antarctic summer can survive in the winter without food". "As soon as they get older one year they can quickly through the winter." "Would you warm winters these long lines of two, three, or four ice-free, and it would be for any survival of the krill directed."
"We have the pieces of the puzzle together and said, what drives the Penguin declines is a change in the climate," he concluded.
The krill loss seems that are the hardest hit recent penguins. Previously returned was to breed about half of the penguins in their second or third year. Now survive only about 10 percent.
Although neither Penguin is classified as endangered species, are researchers of the chinstrap Penguin of penguins future worried.
"Their entire population of the world pretty much in the region is included, which is warming dramatically," said Trivelpiece. Adélie penguins, life in the meantime, in Antarctica.
The penguins eat not always krill. 200 Years ago, they ate a diet largely of fish. But such as whaling and seal hunting other top predators in Antarctica on krill celebrated wiped out, Plankton-and its population moved the penguins on the easy to catch expanded.
The recovery of whales and seals is additional pressure on the krill populations, and so far there is no indication that have returned the penguins eat significant amounts of fish, especially because the fish stocks do not seem, recovering from severe exhaustion in the middle of the twentieth century habenTrivelpiece said.
The krill losses more than the profits deleted penguins made, if they live on krill, he said.
"The data is now that a wrench of the whole system added the warming trends, and things change faster than they historically and through geologic time, have," said Steven Elmslie from the University of North Carolina Wilmington.
"The penguins of the peninsula were the most telling as far as the effect of warming and what can happen in the rest of Antarctica, if warming continues," he said.
"Everything comes back to the decline in sea ice," added Hugh Ducklow of the marine biological laboratory in Woods Hole, Massachusetts
Although researchers previously penguins would Adélie without them for the winter needs suffer pack ice predicted, the new paper suggests what's more krill is important.
"But of course, the decline in krill basically comes back to the decline in the sea ice also."
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