River Otter Research Paper

In a documentary film directed by Bill Wisenski, “Threatened: The Controversial Struggle of the Southern Sea Otter,” it reveals some of the reasons why the California sea otter population is declining. In addition, it shows the controversy surrounding the “No Otter Zone”. Furthermore, it ensures why the California sea otter population is important to the marine ecosystem. In the film, sea otter populations are endangered because of the significant impact by some human factors. In the 1700’s and 1800’s, fur traders hunted sea otter population to near extinction. Besides this, threatened events such as shipping and drilling oil across the Pacific and along coastal areas; the California sea otters is vulnerable to oil contamination. As a result,

The study conducted by Weisle, Nagaswami, and Peterson is displayed about river otters and how they are different in structure from other marine mammals. River otters must depend on their thick layer of hair for survival. River otters are semi-aquatic mammals, which are considered to have denser fur than any other mammals. It’s thick, sleek coat, which keeps it dry and warm, is made up of two types of hair. The longer outer hairs are water repellent as known as guard hairs, and the other is underhair. The guard hairs could provide some protection for the more delicate underhairs. The three authors of this article, “River otter hair structure facilitates interlocking to impede penetration of water and allow,” addresses a question upon why the

The lecture explained how the population of sea otters declined, due to the environmental pollution. First, the oil rigs along the Alaskan coat serve as an indication to pollution. This directly refutes the reading passage which states that predation was most likely the reason, since the bodies of the dead sea otters didn't wash on the shores.Secondly, the passage mention that the water samples that were extracted from the sea revealed the presence of chemicals. Again, this contradicts with the lecture which claims that the whales which the otters consume were not available anymore. Which had forced the sea otters to change their diet to include small sea animals. Thirdly, the lecture mentions that the decrease in sea otters population was

Southern sea otter lives in kelp forests (a type of seaweed) along the Pacific coast, mainly off the coast of California. The marine mammals consume on average one-fourth of its weight daily including sea urchins, which are vital to support the kelp forests. By the result of sea otters preying on sea urchins, the consumption of kelp by sea urchins are kept at a constant rate allowing the forest to grow and thrive. This is highly important for biodiversity in the sea that is provided by the kelp forest, which is a key component of the three principles of sustainability. There are three ways that human can do to help prevent the premature extinction of southern sea otters. First, ethical issue that consists of the species being seen as vital

Arctic fox is small animal that can reach 26 inches in length and 6.5 to 17 pounds of weight. Bushy tail is usually 13.7 inches long.

Sea otters (Enhydra lutris) are marine mammals capable of spending their entire lives in water. Being carnivorous in nature, they feed on sea urchins, crabs, fishes, mussels and clams. They are referred to as keystone species due to their profound impact on marine ecology. The interaction between sea otters, sea urchins and kelp forests has been studied as a model for the impact of predator-prey interactions on community ecology. Sea otters are keystone predators, whose presence has a far-reaching influence on the marine food web by affecting the populations of sea urchins, which indirectly affects the populations of kelp

The sea animal I chose was a southern sea otter. Sea otters inhabited the North Pacific Rim of the Pacific Ocean, from Hokkaido, Japan, through the Kuril Islands, Kamchatka Peninsula, Commander and Aleutian Islands, Alaska, and south along the west coast of North America down to Baja California, Mexico. Scientist have evidence found in fossil records, that sea otters and their relatives have been a major part of the California’s ecosystem for the past five million years but by 1830 sea otters became very rare in California. Scientific evidence to suggest Otters have been on Earth for the past 23 million years. It is speculated that the Otter as it is today could have evolved monumentally about 7 million years ago.

Finally, the unpatterned of sea otter decline is attriputed to Orca hunting area accessibility not due to water pollution as the reading indicated. The professor mentions that, due to it large body size, Orca can not access shellow water or rocky area. However, they hunts perfectely in a deep water. Therefore, sea otters number increase in shellow water and rocky areas and decline at deep water. Thus, this explain the unpatterned of sea otter decline.

The lecture talks about the cause of the decline of sea otters and attributed that to the predidation. However, the reading claims that the decline of the sea otters is because of the pollution.

The reading passage tries to give some reasons to show that the number of sea otters, a small mammal living along the western coast of North America, has significantly declined because of the environmental pollution. On the other hand, the professor on the lecture looks at this concept through a different lens and believes that attacking by the predators like orca are possible for this problem.

In the 1700-1800s sea otters were nearly hunted to extinction. They became listed under the Marine Mammal protection and Endangered Species Act and the gained protection with the signing of the International Fur Seal Treaty of 1911. Sea otters eat many of the same shellfishes that humans like to eat, such as sea urchins, crab, and lobster. Since sea otters like to eat the same kinds of food we do they often find themselves in the same areas where fisherman fish at. Some shell fishers see the sea otters as a competition and a threat to their fishing areas. To help them eliminate their problem of the sea otters they have fishing gear that entangles them which causes them to drown. The fishing traps and nets poses as a major threat to sea otter population.

The dorsal fin is triangular, and has been know to grow in excess of 6 feet in length on males, but grow no more than 3 feet on females. (Martin) The pectoral fins of the orca can measure up to one sixth of it’s body length and is in the shape of a paddle. The orca usually have 40-50 conical teeth which measure over 2 inches in length, and has a perfect fit with the opposite set which makes it an excellent hunter. Although the teeth are robust, they do a lot of work through the years because older orcas have been known to have teeth worn down to the gum tissue (Haley.) The tongue of a killer whale has been known to weigh in excess of 2 tons (Martin.) They have been known to be fearless hunter, and a fast predator. Some say the ferocity of the killer whale exceeds that of the great white shark, which makes it one of the most feared in ocean life.

Sea otters are a keystone species, meaning their role in their environment has a greater effect than other species. As predators, sea otters are critical to maintaining the balance of the near-shore kelp ecosystems. Without sea otters, the undersea animals they prey on would devour the kelp forests off the coast that provide cover and food for many other marine animals. Additionally, sea otters indirectly help to reduce levels of atmospheric carbon dioxide, a prevalent greenhouse gas, as kelp forests play an important role in capturing carbon in coastal ecosystems

Throughout my life, I have been through many different things. I have been through struggles and successes. I have been through multiple setbacks and breakthroughs. There is one specific setback, however that is very important to me that I overcame. It was not easy, but I finally did it. This setback took place during the time between when I entered high school and the end of my sophomore year.

The death penalty in the U.S. is a very serious concern still to this day. Capital punishment is the same exact thing as the death penalty, it is a governed sanctioned practice to put a person to death. The death penalty effects all people whether it be because of the crime the person committed to receive the death penalty or the person’s family. This is a major controversy in the U.S. because some people think that you should not put a person to death or keep them locked up for doing something that is not a norm. While others believe that you must have some type of punishment so that people will be more likely to not commit a horrible crime. When people do commit egregious crimes, like murder or rape, they are to be punished by law if proven