Penguin Populations Plummet Due to Rising Temperatures
It's not just the polar bears who are losing their habitat due to melting sea ice. A new study by researchers from the Woods Hole Oceanographic Institution (WHOI) finds that Emperor Penguins, the species that starred in March of The Penguins, may eventually disappear as their habitats vanish.
The flightless birds live in Antarctica and, unlike other birds, raise their young almost exclusively on sea ice. If that ice breaks up early in breeding season, it could drastically limit the number of penguins born to replenish the colony, according to biologist and study leader Stephanie Jenouvrier of WHOI.
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This population decline has been seen before with the Dion Islets penguins of the West Antarctica Peninsula.
"In 1948 and the 1970s, scientists recorded more than 150 breeding pairs there. By 1999, the population was down to just 20 pairs, and in 2009, it had vanished entirely," Jenouvrier said.
She thinks the loss of those penguins may have been due to warming temperatures in the region, and the problem could be repeating itself.
Warming temperatures also affect the penguins' food source, as they feed on fish, squid and shrimp-like krill, which in turn feed off of zooplankton and phytoplankton growing on the underside of sea ice. The sea ice melt could create a domino effect, which would ripple through the food web and make it harder on the already waning penguin population.
"As it is, there's a huge mortality rate just at the breeding stages, because only 50 percent of chicks survive to the end of the breeding season, and then only half of those fledglings survive until the next year," Jenouvrier said.
Using climate models to simulate sea ice melt at key times during the year - during egg-laying, incubation, when rearing chicks, and non-breeding season - researchers at WHOI predict that if greenhouse gas emissions remain the same as today and temperatures continue to rise at their current rate, the number of breeding emperor penguin pairs in a colony in East Antarctica will drop by 81 percent over the next century. By 2100, the population could drop from about 3,000 down to just 500 pairs.
"Understanding the effects of climate change on predators at the top of marine food chains-like emperor penguins-is in our best interest, because it helps us understand ecosystems that provide important services to us," said WHOI biologist Hal Caswell, according to The Epoch Times. Humans rely on nutrient cycles that involved species in the oceans all around the world, he adds.
"People say the temperature may increase by two degrees, so what?'" Jenouvrier told ABC News. "But changes that may seem small to humans are not small to species, and may affect the entire ecosystem."
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