The reading and the lecture give information to explain the reasons that lead to rapid decrease in the sea otter number. While the reading looks at the topic ffrom one perspective the reading challenged the idea illustrated in the reading passage.
First, the reading indicated that water pollution contributes to the rapid decreas in the sea otter number. the reading explains that water pollution resulted from oil ridg and indu sterial activities have lead to increase chenicals in the water, which pose great risk on sea otters. Also the reading emphasize that due water pollution not only sea otter population number was affected but also others sea mammals like sea lions and seals population number are decreased too. Finally, water pollution
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The lecture indicated that the rapid decline in sea ottor number is contriputed to predators like Orca. The professor mentions that Orca hunt and eat sea otters. Therefore, no sea otters bodies are washed out in large number. If there is water pollution, sea otters bodies should be wahed out along the coast line in larg number. Thus, this why the professor refute the water pollution hyposize.
Second, the professor mentions that there are increasing evidence that predetators are the main cause of sea otter decline. he mentions that, since Ocras favourite meals, the Wheals disappered or decrease on number, Orcas tend to nurich on small mammals like seals, sea otters and sea lions.
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.
Overall, it seems that the lecture showed that ther are some disscrepancies in the ideas illustrated in the reading
I believe that underwater noise has an effect on marine animals such as whales. Using information from the passages I will prove my point. Their numbers are declining rapidly and I believe that underwater noise has some involvement in the rapid decrease in their population numbers. The information given within the two passages will help prove my point.
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
The area of research that I have selected is the effects of overfishing in the Sea Otter ecosystem off the coast of California. The effects caused by the fishing pressure on the ecosystem will have different outcomes, depending on the strength and the types of relationships of the organisms present. (4) Red Abalone populations have declined drastically, to the point of the abalone fishery collapse. Several factors have led up to the collapse including Withering Syndrome, where the organism loses the ability to attach itself to rocks, making it more susceptible to predation, or the organism can eventually wither and starve to death. Sea Urchins and Red Abalone are a part of the same ecosystem, and are competitors of each other.(5) Both organisms graze on macroalgae and are a primary food source for Sea Otters. Sea Otters occurred from the North Pacific Rim down to Baja California, Mexico, but now only occur in small isolated patches (9) It is understood that Sea Otter presence can characterize community structure, where they can control and determine the size of Sea Urchin and Red Abalone populations. In the absence of Sea Otters, “Urchin Barrens” are created from the overgrazing of macroalgae by Sea Urchin. In these areas the ecosystem have changed dramatically, due to the overfishing, or in this case the over hunting, of Sea Otters causing a trophic cascade.(7)In some areas, Sea Otters have been reintroduced, in other areas they were never removed, and in others they
Sea Otters as well as many other species are in danger because of Climate Change.The sudden change in climate has disturbed the ocean’s temperature which causes an insufficient amount of food for sea otters which causes the otters to be malnourished and starved. Because of the change in climate there has been a decrease in the amount of harp seals (Foley, 2013) which happens to be the killer whales main prey, because of this the killer whales have now turned to sea otters. Other likely threats to sea otters because of climate change are ocean acidification in the north Pacific, pathogen transport, marine invasive species, biotoxins withdrawn in bivalve prey, and the recurrence and intensity of storm events (Doroff and Burdin, 2015) . Sea otters have a noticeably solid influence on the wealth of kelp through the impact they have on sea urchins, said James A. Estes, a professor of ecology and evolutionary biology at the University of California, Santa Cruz who was a co-author on Schmitz 's 2014 review and on the original sea otter study. Otters eat urchins. Urchins eat kelp. So in ocean patches where otters are bountiful, urchin populations collapse and kelp tends to thrive (Estes,Cruz and Schmitz,2014). The study, led by Wilmers and published in 2012, found that across the otter 's range the animal could be indirectly at fault for getting rid of as much as 8.7 million tons of carbon dioxide, more than twice what an average
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 lecture and the article cover the decline in sea otters population in the recent few years. Two main theories arised to explain that rapid decline. Pollution is suggested as the main reason behind this decline by the author. However, the lecturer opposes that. He believes that Predation is the main cause.
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
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
In this article “saving the sea otters is just part of her normal day at work” by Kitson Jazynka My Opinion was that I think a lot of the sea mammals are dying because the bacteria in the water. First of all,”Otters in Alaska have been dying at a higher than normal rate over the past 10 years.”This quote
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.
SInce the dawn of time humans have been constantly evolving and at the same time ravaging the earth. The Otters know this, which is why the Otters see the humans as a great threat, but on the other side
Sexually mature females can mate year around and are often either pregnant or caring for young throughout their lifetime, and this creates ongoing energy demands that can be energetically exhausting (Chinn et al. 2016). Sea otter mating behavior is aggressive and can further inflict physiological and traumatic stress to females, thereby reducing their foraging efficiency. Other factors such as infections, disease, bio-toxin ingestion and anthropogenic disturbance can also decrease fitness among adult females and increase their vulnerability during reproduction (Chinn et al. 2016). As nearshore inhabitants, southern sea otters often live in close proximity to areas of high human population density in California. These nearshore waterways can be busy with recreational and commercial boating activity that can disturb sea otter populations. Increased disturbance may cause increased stress to the species. Sea otters are of great interest to people who wish to view them, and this is sometimes done up-close by boat or paddle craft. If this activity changes sea otter behavior in any way, it not only violates the Marine Mammal Protection Act, it can also have a negative impact on the species, especially adult females with pups. Additionally, a familiar list of human impacts, such as climate change, overharvest of marine resources, municipal runoff, and habitat degradation likely reduce fitness of marine mammals directly and indirectly. Sea otters can be indicators of the overall health of the nearshore ecosystem (Kreuder et al. 2003). The slow growth rate of the southern sea otter population may be an expression of nearshore ecosystem degradation in California resulting from the fur trade and explosion of human population in
In the listening passage, professor focuses on 1 effect of rapidely declining of sea otters in Alaska coast in North America has more affect. In the reading passage, 2 causes of this event are presented. One of them is pollotion that is made by chemical factories and also attacing predators such as seals, sea lions, and orca. The professor emphasis that attaching prdators has more effection on declining sea lion rather than pollotion. She has some reasons for supporting his oponion. First one is that there are a few chemical factories and also the amount of their pollotion is low therefore, pollotion has weak affect on death of sea otters. Second one is that the predator animals disappear due to their changing diet. Third one is that in some
They also live on every continent except Antarctica and Australia due to its weather and temperature conditions. In the big picture of life, River Otters are most commonly found on the coast. According to The News Press, “River otters are common in fresh water all over Florida. Residents living along the Imperial River and Estero River see them quite often playing in the water and scurrying along the banks. Visitors spot them sliding across the path from one lake to another” (Stetson). Based on the body and needs of River Otters, it is essential that they are near water. Their swimming skills and diet also affect the need for them to be near water.
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 of the impact of predator-prey interaction on community ecology. Sea otters are keystone predators, whose presence has a far-reaching influence on the marine food web by affecting the population of sea urchins in particular, and kelp forests & other marine organisms in general. There has been a steep decline in sea otter populations due to water pollution and exploitation for