.. ts own body temperature. Often chicks herd together in tight groups to keep warm from the freezing arctic air. The eggs of penguins tend to vary from species to species in regards to size, shape and weight. The colors of penguin eggs tend to be white, bluish or greenish.
A chick depends on its parents for survival between hatching and obtaining its waterproof feathers. Once a chick has lost its down feathers and they have been replaced with waterproof feathers, the chick is able to enter the ocean and become somewhat independent of its parents. Penguins are very efficient swimmers and; although they are used to swimming at speeds of 5 mph, some of the species can travel up to speeds of 8.9 mph, such as the Emperor penguin. When penguins are traveling through the water quickly, they will leap out of the water every few feet. This type of action is called porposing due to the same behavior that resemble a porpoise.
This action serves 2 purposes for a penguin; one being that a penguin needs to come up for air, and the other is to decrease their chances from being eaten by a predator. When penguins are out at sea feeding, their diet is made up of krill, squid and fish. Smaller species of penguins feed on krill and squid whereas larger species tend to feed on squid and fish. Penguins rely on their eyesight when they are out hunting for food. It is not known how penguins locate their prey in the darkness, at night, or at great depths, but some scientists hypothesize that penguins are helped by the fact that many ocean squid, crustaceans, and fishes are bioluminescent (they produce light).
(del Hoyo, et al., 1992) When penguins are hunting for food, they catch their prey as they are swimming and swallow their food whole. Feeding areas vary for each species of penguins. When hunting for food they may be successful within a 9-mile radius, or they have been known to travel as far as five hundred and fifty nine miles to find food. As penguins are swimming in the ocean waters, they have several predators including but not limited to; leopard seals, fur seals, sea lions, sharks or killer whales. On land, penguins have to worry about other predators such as foxes, snakes, and others that are not native to the lands but that have been transplanted by human migration.
Examples of some of these non-native predators are; feral dogs, cats and stoats, which is a member of the weasel family. Since penguins are the most aquatic of birds, El Nino has taken its toll on the existence of these fascinating creatures. This natural phenomenon, which changes wind and ocean current patterns, warms the surface temperatures and reduces the upwelling of nutrient-rich water. Marine animal food supply is directly affected and compromised by the above mentioned factors because of the decrease of nutrients within the water. Plankton, krill and small fish cannot thrive under these changes. To put it simply, the waters too warm and theres not enough food. (Boresma).
Water temperatures in the equatorial Pacific Ocean have been measured from eighty-three to eighty-four degrees Fahrenheit; which is much warmer than normal and, because of this, fish found in these waters cannot survive, they die or migrate. Penguins found in this region are undernourished and/or emaciated, with an absence of young or baby penguins. Because of the shortage of food caused by El Nino, researchers have found that adults do not attempt to lay eggs. When eggs are laid however, many nests are left abandoned because the birds do not have enough food to remain in the area. When upwelling is absent, the birds forage singly or in pairs, they do not molt, and the few that initiate breeding rapidly lose weight and eventually fail. (Williams, 1995) This contributes to the increasingly low penguin population and is directly caused by El Nino.
El Nino is a naturally occurring phenomena which cannot be controlled; however, the actions of humans and their subsequent effects on the population of penguins can be controlled. The biggest threat to marine species is the human impact. The killing of penguins dates back as early as the 1800s and was a major factor in the mortality rate of penguins. Penguins were hunted and killed so that the fat from their fat layers containing oil could be harvested and used for lighting, tanning of leather and fuel. This was an important source of obtaining these necessities in the 1800s and early 1900s. Penguins were hunted and killed by early explorers for use as daily provisions; their carcasses were dried and salted for consumption. They were also a source of fresh daily meat. Fortunately for the penguins, their eggs were a more important food supply than themselves. Sailors on long voyages consumed large quantities of eggs in vast numbers as these eggs contained an immense amount of protein.
Sometimes more than 300,000 eggs were taken at an annual harvest from one African Island. (Sparks and Soper, 1987). The collection of penguin eggs is illegal and has been since 1969; however, believe it or not, it still continues to occur even today. The illegal killing of penguins also still occurs today as their meat is used for human consumption, as well as fishing bait in Chile and Peru. In addition to penguins being hunted currently and in the past for use as a food source, they have great commercial value as nitrogen-rich fertilizer.
The use of penguins as a fertilizer dates back as far as 500 B.C. The Incas used penguin and seabird guano to improve their crops. However, the Incas were careful to not over use their supply by limiting its use based on the rate that the penguins reproduced themselves. Today penguins are still a source for commercial nitrogen-rich fertilizer; however, today those harvesting it are not as thoughtful. Overexploitation for this use is seriously threatening some species and their population. The dumping of garbage and trash in the ocean affects all kinds of marine life including the penguins. Penguins have been found tangled in debris, which causes death or serious injury. In addition to trash dumping, oil dumping also poses a great threat to the penguin population.
When their feathers are tainted with oil, weatherproofing is reduced and their insulation fails. They are then at great risk of hypothermia. In addition, when trying to preen their feathers; they can ingest oil, which poisons them and causes their internal organs to fail. Although oil spill disasters such as the Exxon Valdez spill off the coast of Alaska had a devastating affect on the population, oil also enters into the waters via ship sludge and residue. Facilities are available for ships too properly dispose of their sludge and residue; however, unfortunately these facilities may not be utilized as it may be cost prohibitive and therefore, illegal dumping is then opted.
The dumping of oil waste is permitted; however, the rate must be 15 parts of oil to a million parts of water. This formula is not followed as the risk of being caught is so small compared to the cost of the mixing of the formula. Oil also enters into the marine habitat through land run-off. The U.S. Academy of Sciences estimated in 1990 that 37% of oil pollution of the worlds marine environment enters the sea from the land. Other sources estimate that 45% comes from shipping (12.5% from tanker accidents); 9% from the atmosphere, 7.7% from natural sources and 1.5% from offshore oil exploration and production.
(Environmental News Network). In conclusion, the responsibility for the future existence of the penguin population lies mainly with the human race. Our ability to cause changes in climate snowballs thus creating changes in global and local patterns of ocean productivity. We have altered, and continue to alter, the natural environment and habitat of these wonderful creatures. Historically, the direct exploitation of penguins by humans created a huge risk to their survival.
Currently, as humans create more creative uses for penguins and their skins, we pose a greater risk of impacting their existence. The ability to control and monitor the use of these animals is complex and difficult. The need for protecting marine habitats for all kinds of marine life has become serious. We have the ability to cause the extinction of far too many creatures. As of December 4, 1998, a number of conservation groups gathered and formulated a report on the penguin population. They believe that 9 penguin species should have been endangered or were close to being endangered, and 2 more species close to being threatened. Previously, only 5 of the total seventeen penguin species were considered threatened. Based on the above-referenced conservation groups statistics, more than 50% of penguin species may be close to endangered.
If we do not take an active stand on the protection of these amazing birds, we stand a chance of creating yet another dinosaur, available to our children only through history and science books. Science Essays.