Data Bases • Custom Term Papers • Free Term Papers • Free Research Papers • Free Essays • Free Book Reports • Plagiarism? Links • Top 100 Term Paper Sites • Top 25 Essay Sites • Top 50 Essay Sites • Search 97,000 Papers @ DirectEssays.com • Search 101,000 Papers @ ExampleEssays.com • Search 90,000 Papers @ MegaEssays.com Free Essays • Term Paper Sites • Chuck III's Free Essays • Free College Essays • TermPaperSites.com • My Term Papers • Get Free Essays • Essay World • Planet Papers	Search Lots of Essays Back to Subjects - European History what effect has el nino had on seals and sea lions what effect has el nino had on seals and sea lions El Nino, also called the "El Nino-Southern Oscillation" or ENSO, is a change in the ocean-atmosphere system in the eastern Pacific that occurs about every five to seven years. It contributes to significant weather changes around the world, according to the National Oceanic and Atmospheric Administration. Among these changes are increased rainfall across the southern region of the U.S. and in Peru and drought in the West Pacific, affecting Australia and its neighboring nations. During El Nino, the winds at the equator blow from west to east in the Pacific. These winds travel along the surface of the ocean and bring warm surface water heated by the tropical sun to the western coasts of North and South America. Rainfall follows the warm water eastward, with associated flooding in Peru and drought in Indonesia and Australia. A key indicator of El Nino is usually warm temperature along and on both sides of the equator in the central and eastern Pacific. The warming typically starts in the north during late spring or summer and builds to a peak at the end of the year. The events are usually over by the following summer. The changes in ocean temperatures affect the atmosphere. The hot, humid air over the oceans fuels tropical thunderstorms. The hotter the air, the stronger the thunderstorms. As the warmest water spreads, the biggest thunderstorms follow, or move, with it. These thunderstorms pump warm air and humidity more than 50,000 feet into the air. El Nino has had an impact on many nations around the world. Some places got hit with heavy rains and floods, others faced drought, poor crops and starvation. Many different species of fish migrated and coral reefs got damaged. Santiago, Chile has suffered from severe flooding from heavy rainfall and snow. Drought conditions were felt in northeast Brazil, southeastern Africa, and the west Pacific. Pakistan and northwest India were dry, and the normal monsoon rain was spotty in parts of India. Southeastern Africa and northeastern Brazil experienced dry conditions, which reduced crops and resulted in starvation. The warmer water temperatures caused many corals to be in water that exceeded their upper temperature limit. When water temperatures rise too high, the corals are subject to bleaching, which often leads to their death. The warmer waters also disrupted fish migrations worldwide. Warm water fish such as tuna migrated to cooler water and were spotted off the California coast. Tropical and temperate marine species pushed northward beyond their normal ranges in search of food. The Peruvian fishing industry has suffered as the anchovy supply pushed south into cooler, Chilean waters. Salmon, usually found off the Oregon and Washington coasts, were forced to swim into cooler Canadian waters. The decreases in the marine food supply also led to the stranding of seals and sea lions along the West Coast. The main point of this paper is to focus on those sea lions and seals and to show what changes El Nino brought to them. El Nino has had a great effect on seals and sea lions everywhere, causing many to die and emaciating those that survived. Thousands died in South America alone. At the height of the most recent El Nino, the Pacific Ocean surface temperatures near the Paracas Peninsula in Peru rose from the cool, normal range of 56 to 58 degrees Fahrenheit to 81 to 83 degrees Fahrenheit. As a result, schools of anchovies and sardines migrated to cooler waters, following the plankton they feed on, and the sea lions of that area were forced to go farther in search of food. Mother sea lions normally spend one to two days away from their pups searching for food to make milk to nourish the pups, but because they had to search farther, they had to spend more than twice that time away from their pups. Because of this, the pups either died of malnutrition or were close to dying of malnutrition. Not only did the pups die from malnutrition from not being nourished from their mothers, but they were also malnourished because their mothers’ milk was poor in nutrients from the lack of food. Similar conditions were seen all along the coast Peru and the ecosystem there slowly fell apart in a domino effect. Infact, only eleven of the one thousand pups produced on Peru’s North Ballestas Island would survive, the rest dying of the same thing as those on the Paracas Peninsula. Sea lion pups also died in masses on the coast of Chile. Fish in Chile are also being pushed from their normal limits and instead of spending more time away from their pups searching for food, mother sea lions are just abandoning their young. Sea lion pups normally have a weaning, or nursing, period that lasts for six to ten months. During this time the pups learn how to search for their own food to survive while being nourished by their mother’s milk. However, mother sea lions are abandoning their pups and cutting the weaning period to one to three months. Thus, the sea lions do not get any nourishment from their mothers and don’t know how to get nourishment by themselves and die. The same two conditions were also seen along the California coast where over sixty percent of the seal and sea lion pups died. Their mothers’ diet of anchovies, squid, hake, octopus, sardines, lantern fish and other small marine creatures also moved to deeper waters or waters further north. In addition to this, many Elephant seal pups drowned off the coast of California because El Nino caused their rookeries, or “pup nurseries”, to flood. El Nino has also been held responsible for killing more sea lion pups on the Auckland Islands and for severely hurting the already endangered population of sea lions on the Islands. About sixty percent of the pup population was killed by some unknown cause. Scientists on the Islands are not sure of what the cause of the deaths is. However, they suspect it to be some sort of algal bloom or bacteria or virus caused by El Nino. It is believed that the changing of sea currents caused by El Nino upset the food sources and somehow brought the infection to the Islands. Tissue samples were sent to New Zealand and as far away as New York to be tested to find out what the infection was and, if possible, to make a vaccine to vaccinate uninfected colonies. When the testing was done, the labs had not found out what the infection was, but a vaccine was no longer needed because the deaths had ceased after a few weeks. However, they did find that it was similar to unknown infections killing hundreds animals on nearby Campbell Island and in Europe’s Atlantic coast. Today, scientists still do not know what killed the sea lions on the Auckland Islands. There were mixed opinions as to what should be done about the seal and sea lion deaths that occurred during the most recent El Nino. In the United States, laws had protected sea lions from being hunted. Now, there is an abundance of sea lions and fishermen see them as pests. The sea lions are not hesitant to go into fishing nets after the caught fish. Researchers say that there are too many of them anyway and that even though it is hard to watch the innocent pups die, the El Nino was just one of natures way of evening out things. However, people with kind hearts and environmentalists groups continued to pick up the weak pups. Cautioned by experts, they risked being bitten by the pups with large sharp canines. El Nino has, and will still continue to, greatly affect the seals and sea lions, killing thousands of them every year, when El Nino strikes. Scientists are puzzled by the fact that if El Nino doesn't kill the seals, there might be too many of them, but they don't want to see the pups die without doing anything. Therefore, the El Nino is a troublesome case for many scientists. The warming caused by El Nino not only affects seals, but also many other species of marine life and natural regions of places as well and the hearts of people and environmental groups. Bibliography: “Biological El Nino Effects” Downloaded from atmos.washington.edu the website of the University of Washington, Department of Atmospheric Sciences. “El Nino Blamed: Sea Lion Pups Dying in Chile.” Downloaded from ABCNEWS.com. 7 April 1999 Hughes, Katherine. “What is El Nino?” Downloaded from ENN.com, the Environmental News Network website. 22 September 1997 Johnson, Tim. “Battered by El Nino, South American Sea Lions and Seals Succumb to Hunger” The Miami Herald 28 July 1998 Kay, Jane. “El Nino Killing Seal Pups.” San Francisco Examiner 6 February 1998:pA18 Kay, Jane et. al Samuels, Adrienne P. “El Nino’s Harsh Toll on Fur Seal Pups.” San Francisco Examiner 13 November 1997: pA1 Moser, Doreen. “Is El Nino Here? Ask a Fur Seal.” Downloaded from tmmc.com, The Marine Mammal Center website. 5 May 1999 “Scientists Distressed By Sight of Dead Sea Lions” Downloaded from whalewatch.com 25 February 98 “So What is an El Nino Anyway?(a non-technical description)” Downloaded from meteora.ucsd.edu, the Scripps Institute of Oceanography website 5 May 1999 Terry, Don. “Battered Sea Lions Find Refuge from El Nino.” The New York Times 16 February 1998: v147 pA9 “What are the Effects of El Nino?” Downloaded from glys.com. Wong, Jeff. “Thousands of Sea Lions, Seals Dying of Starvation. El Nino Blamed for Reducing Food Supply.” The San Diego Union-Tribune 15 December 1997: pA3 Word Count: 1373
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