TPO 10 Integrated Writing Task The sea otter is a small mammal that lives in waters along the western coast of North America from California to Alaska When some sea otter populations off the Alaskan coast started rapidly declining a few years ago it c

The lecture refutes the reading that shows pollution causes a decline in sea otter population. Providing three reasons, the lecture suggests predation by sea orcas leads to the disappearance of sea otter.
First, the lecture points out a lack of evidence to prove pollution cases a decline in sea otters’ population. The lecture emphasizes on the reading overlooked the fact that no dead sea otters were found on the seashores, which weakens the credibility of pollution theory. Because of an absence of the dead bodies of sea otters, they are more likely to be eaten with their whole bodies by predators such as sea orcas.
Second, the lecture explains that sea otters are at greater risk of sea orcas to clarify the cause of a decrease in sea otters as well as other small mammals population. The reading assumes that the pollution threatens small mammals including sea otters, introducing that sea orcas, the predator of sea otters, prefer to eat big sea mammals such as whales. Although she admit the eating habit of sea orcas, she reveals that whales are also disappearing. She describes that the whales disappear due to overhunting by people, which forces sea orcas to hunt smaller sea mammals including sea otters. Therefore, decrease in whale population increases predation risk on sea otters and other small mammals since sea whales have become less available for sea orcas.
Third, the lecture suggests the correlation between the accessibility to sea orcas and the sea otter population to bolster her predation theory. While the reading suggests uneven patterns of sea otter population, the lecture clarifies predation risk creates different population densities of sea otters. She expounds on that sea orcas cannot access to shallow and rocky locations because of their large body size. She highlights the population of sea otters has not declined in those locations, which presents the tangible evidence to explain sea orcas is the major factor of sea otters’ decline.
In conclusion, the lecture argues that predation by sea orcas causes a great decline in sea otters’ population, refuting the three points made by the reading that attributes oil and chemical pollutions to the cause of the disappearance of sea otters.