the study suggests krill availability affects the tendencies of the penguins, such as Chin straps is a series of penguin species in Western Antarctica found as a result of a decline in the availability of krill decline, a study has suggested.Researchers, investigate 30 years of data, said chinstrap Penguin and Adelie Penguin numbers had fallen since 1986.
Warming water, less sea ice cover and more whale and seal numbers was the most important food source for the penguins as a reduction in the abundance of krill.
The results appear in the proceedings of National Academy of Sciences.
The Antarctic krill (Euphausia superba) is a shrimp-like creature, which reach lengths of about 6 cm (2) and considered to be one of the most common species on the planet, in dense of up to 30,000 creatures in a cubic meters of sea water is found.
It is also one of the most important species in ecosystems in and around Antarctica, as it is the dominant prey of most vertebrates in the region, including chinstrap Penguin and Adelie.
Change warming
In their paper said a US team of scientists from the National Oceanic and Atmospheric Administration (NOAA) and the Scripps Institution of oceanography a number of factors are combined, change the shape of the area environment.
"Support of the West Antarctic Peninsula (WAP) and adjacent Scottish see abundant wildlife population, many of whom almost were [extinct] of people," they wrote.
"This region is also to the fastest-warming regions on the planet, with 5-6 C increase in the average winter temperatures of air and associated decrease of sea ice winter cover."
You, that surveys covered the analysis during 30 years of field studies and the last Penguin data added to a leading scientific idea, known as the "sea ice hypothesis", about how ecosystems was the region can change.
"(It) proposes that cuts have led in the winter sea ice directly to the decline of the 'ice loving' habitat types by reducing their winter while species have increased ice avoidance," explains.
However, you said that her research showed that since the mid-1980s, a decline in ice-loving Adelies had it (Pygoscelis ash) and ice prevention of Chin band (Pygoscelis Antarctica), with two populations by up to 50% drop.
As a result, a "robust" hypothesis, that were connected by their most important source of food, krill Penguin population numbers on changes in the abundance encourages researchers.
"Linking trends in abundance Penguin with trends in krill biomass explains why populations increased from chinstrap Penguin and Adélie penguins to competitors (seals, baleen whales and some fish) in the 19 to the mid-20th century are almost extinct and currently reduced in response to climate change" they wrote.
The team said that it was estimated that in the region of 150 million tons of krill for predators after the global hunting era consumed world's whale population.
During this time, data shows that there is a five-fold increase in chinstrap Penguin and Adélie numbers to breeding grounds in the 1930s, the 70's they reported.
"The large populations of chinstrap Penguin and Adélie penguins were not consistent long, however, and now in steep decline."
She added that this was done as rising temperatures and fall in the sea ice was change the physical conditions to maintain populations large krill.
"We hypothesise that the height of the krill available declined to penguins, due to the increasing competition from the recovery of whale and fur seal populations and from bottom to top, climate-driven changes that significantly changed this ecosystem during the last two to three decades."
Were the US researchers found that the Penguin numbers and krill abundance probably fall further if the warming trend in the region continued.
They wrote: "These conditions are especially critical for chinstrap Penguin penguins, and Scotia sea, where they suffered declines of 50% of their breeding area because such breeds almost exclusively in the WAP."
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