Pollution: The Decline Of Sea Otters

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 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

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

One hypothesis proposes that the reason Steller sea lions have been declining is because of low prey abundance. Animals should use their energy efficiently when they forage to maximize the net amount of energy gained in relation to the amount time and energy that is spent, but it is believed that the reason Steller sea lions are disappearing in such big numbers is because when prey abundance is lower, that Stellar sea lions are less efficient predators (Charnov, 1976). In a recent study conducted on the effect of prey abundance on foraging efficiency, it was found that the less prey that Stellar sea lions had available, the less efficient they were in foraging (Goundie et al., 2015). In the experiment, the researchers took 4 adult Stellar sea lions and had them dive up and down a tube while recording their oxygen consumption, and dive duration. The sea lions dove between the surface of the water and depths of 10 m, and 40 m, and the reason for this was to simulate diving depths of Steller sea lions in the wild (Merrick and Loughlin, 1997). While the sea lions were diving, researchers fed them pieces of fish through two different tubes that were placed away from each other in order to simulate real foraging movements and prey densities. The researchers fed the seals 12 pieces of fish in the

The presence or absence of sea otters influences marine ecology at the community-level. Studies have shown that kelp forests enhance the underwater environment, providing a suitable habitat for fishes. The declining kelp beds in California in the mid 1900’s propelled the Kelp Habitat Improvement Project, whereby attempts were made to eliminate sea urchins that are

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

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.

First, the reading passage mentions that the pollution containing oil and industrial chemicals could pollute the water. In addition, it brings up the fact that the results of recent samplings reveal that the level of these materials is significantly increased in the sea water; therefore, the sea other is unable to resistance with this high level of pollution.

Firstly, the author states that pollution sources such as oil rigs near Alaskan beaches is killing the sea otters. Also, a research held on water samples in the area showed that it contains high levels of chemicals that may indirectly kill the otters. This view is objected by the lecturer. He proposes that Orcas use the animals as source of food, that is why there are no signs of dead otters on shores of Alaska, which would however be

The presence or absence of sea otters influences marine ecology at the community-level. Studies have shown that kelp forests enhance the underwater environment, providing a suitable habitat for fishes. The declining kelp beds in California in the mid 1900’s propelled the Kelp Habitat Improvement Project, whereby attempts were made to eliminate sea urchins that are primary predators of kelps. Studies showed that the elimination of sea otters during the 1800s from the Californian waters might be responsible for the dwindling numbers of kelp forests. Further studies have also shown that the population density of sea otters affects seaweed biodiversity as well. In a study conducted in Alaska on three different bays, the Torch Bay, Deer Harbor and the Surge Bay, it was found that the presence of sea otters led to a decrease in the population of sea urchins, which led to an increase in the population of seaweeds. In addition, it was also found that annual kelps predominated the areas where sea otters were present, and perennial kelps predominated in areas that had lesser sea otter populations (qtd. in “Interaction with kelps & sea otters”).

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

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

However it is critical to understand that when they are conserved in captivity, we prevent them from getting their main biological needs from the ocean as a natural habitat. With their wide food spectrums, orcas hunt for turtles, sea lions, crabs, seals and many other food varieties depending on their ecotypes. This makes them travel over large regions in the ocean in search of the same. Just as human beings are top of the food chain with regards terrestrial animals, so are orcas in the oceans. It is therefore important to raise our voices against this practice to avoid the risk of classifying them as endangered species. Even though the whales “gave me so much in my life and my career” (BioExpedition 1), he grew to believe that the whales’ physical and emotional well-being was incompatible with captivity. Confined to unnatural social groups for the convenience of their owners, bored and restless, forced to perform tricks for food that trainers withheld as punishment, they occasionally slipped, he writes, “into the dark side” (Adler 2).

Cetacean bycatch is an ongoing problem in the oceans of the world. Cetaceans are defined as whales, dolphins and porpoises(CBRC 1). Bycatch is “marine mammals that are “captured” but discarded”(Read 2). This happens when fishing industries are fishing for a certain type of marine animal and other marine animals are caught accidentally along with the intended catch. Many times, this leads to the death of the animal that was not meant to be caught, and the animal is tossed back into the ocean. This happens with all kinds of marine life, and it has caused the depletion of many different species. However, this is specifically bad for cetaceans, such as dolphins and whales, because they have such a long lifespan(Brown 2). They also take a very long time to mature(Brown 2). These factors make catching these animals very detrimental to the species as a whole because it takes longer for them to reach an age where they can reproduce(Brown 2). The population of many cetaceans have decreased exponentially. When there is someone watching the nets that cetaceans are accidentally caught in, many times they can be saved. However, there are only select few types of fishing methods that do this, and they are not of the prevalent fishing methods that produce cetacean bycatch. This is a problem because there is a connection between most living animals. If a certain part of the connection is eliminated, it will all fall apart. For example, the relationship between