Friday, August 2, 2019

The Extinction of Penguins

Emperor Penguins have been around for millions of years. Although they are a type of bird they can not fly. They walk, slide on their stomachs, or swim. They can swim up to nine kilometers an hour. That is faster than an average person can run. Emperor Penguins can hold their breath over twenty minutes and dive over eighteen hundred feet. Another interesting fact about them is that they show no aggression towards humans. The real question is though whether or not Emperor Penguins are on their way to extinction? Some of the reasons why we may think this would be climate change, depletion in food supply, pollution, tagging, and their predators. Climate change is the reason for the Emperor Penguin population to decline by fifty percent over the past fifty years. Penguins use the ice to escape from predators, and to raise their chicks. A temperature increase of 2. 1 degrees Celsius will jeopardize forty percent of the world’s Emperor Penguins. When the ice melts before the chicks have matured and grown their waterproof feathers, chicks that are swept into the ocean are likely to die. If the ice isn’t sturdy enough to last until when the chicks are ready to head out to sea, they aren’t going to be able to raise them. The loss of sea ice for adult penguins can lead to lower food availability, which can result in increased mortality. In Antarctica an Emperor colony has declined from 250 pairs to 10 pairs since 1960, due to rapid loss of the sea ice. Since global climate change has been causing the rapid melting of sea ice, the amount of krill in the southern oceans has decreased in recent years. Krill in which many penguins feed upon, survive by feeding off the algae which forms on the underside of the sea ice. So the reduction in sea-ice which has resulted from climate change has meant there has been much less food for penguins to eat. If this continues to happen the Emperor Penguin population is going to keep on declining. Over fishing of krill, and fish is another factor in helping penguins become extinct. It is putting pressure on food chains and food availability for penguins. Industrial fisheries deplete the penguins’ food supply and entangle and drown the penguins in longlines and other destructive fishing gear. The more fish and krill being caught by humans the less food there is for penguins to be able to eat. Ocean acidification which is caused by the absorption of greenhouse gases like carbon dioxide into the oceans is also harming penguins. Plankton is a major part of the food chain for many fish on which penguins feed. As gases are absorbed into the oceans, they become less hospitable places for plankton and other organisms to live which is less food penguins have to eat. Oil pollution kills tens of thousands of penguins annually. The oil destroys the natural water repellent on their feathers, causing the birds to become vulnerable to hypothermia. Penguins also consume the oil while trying to groom, poisoning them and causing internal organ damage. The oil also kills the penguins’ food and poisons the penguins when trying to eat contaminated fish. The banding of penguins is another issue contributing to the declining population of penguins. The first evidence that flipper bands might be causing damage to penguins came in the 1970s. Zoos reported that the bands would wound penguins’ flippers, especially during the yearly molt, when flippers enlarge. Over a ten year period, banded penguins produced thirty-nine percent fewer chicks and had a sixteen percent lower survival rate than unbanded birds. Banded penguins also had less time and energy to reproduce and care for their young because they spent more time searching for food and provisions and arrived more than two weeks late to breeding areas. The penguins wearing bands expend twenty-four percent more energy while swimming and attract the attention of predators. Rory Wilson, an ecologist at Swansea University said the extra baggage likely increased the drag penguins experienced and impaired their athletic ability.

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