Before the 1700s, it was estimated that sea otters had a population numbered between “several hundred thousand to one million” and now there are just over one hundred thousand in the northern Pacific left due to hunting and environmental impacts (Threats to Sea Otters, 2016). Although sea otters aren’t the biggest mammal in the marine food chain, they are actually the species that is keeping it from all falling apart because they are a keystone species, which means they make a substantial impact on the environment (Keystone Species, 2012). It may be hard to believe that sea otters have the ability to affect the whole ecosystem and even reduce the amount of CO2 in the atmosphere, but it is even harder to believe that they do this by eating sea urchins, crabs, clams, snails, and worms. Even though sea otters have a positive impact on the environment, it has been noticed that they haven’t regained their population numbers ever since they hit their downfall during the fur trade, which raises concern about the integrity of other ocean organisms. Furthermore, sea otters have profound effects on the environment and should be better protected at all costs because they keep the food chain balanced, help reduce the rate of global warming, and create better a water quality.Between the 1700s and 1800s, sea otters were nearly hunted towards extinction by fur traders which brought their population to an all time low, but sea otters finally granted protection when the Fur Seal Treaty of 1911 was signed and they became listed underneath the Endangered Species Act of 1970 (Threats to Sea Otters, 2016). By the time they had gained protection, it was already too late because the population had dropped so dramatically. Since the population was so low, the sea otters couldn’t repopulate fast enough and even though they were protected, some people continued to trap them. Since then, sea otters have regained some of their numbers but it still still far below their original population number. If sea otters were to go extinct, then the environment around them would be dramatically different because “no other species would be able to fill its ecological niche”, meaning that no other organism can do what sea otters do (Keystone Species, 2012). With no other organism capable of replacing the sea otter, the ecosystem would change drastically and there would be a possibility of an invasive species, such as sea urchins, intruding into that habitat. During the 1700s and 1800s, researchers began to notice what the absence of sea otters had done to the ecosystem. During these years, the Commander Islands sea otter population dropped 95% and the islands were almost indistinguishable because all the kelp had disappeared (Estes, 2016). This led researchers to discover that sea otters have a profound effect on the environment by what they fed on: sea urchins. Sea otters feed on sea urchins, crabs, clams, snails, and worms, but the most important of those is sea urchins because they’re responsible for eating kelp, which in turn maintains the viability of other ocean organisms. When the sea otter population declines, the sea urchin population multiplies because there are no other predators around to keep them from devouring the entire population of kelp, leaving the ocean floor almost unrecognizable. This causes a major issue because when the kelp population is reduced, it leaves the land unprotected from strong storm-born waves, it increases the amount of coastal erosion, and it also disrupts the food chain because other ocean organisms like fish can no longer hide from predators, which causes the fish population to plummet. This then causes the predators to find a new prey to feed on and then that population will decrease as well. It would be a never ending disastrous cycle if the sea otter population were to decrease because it affects marine life in such a drastic way. For example, due to the excessive hunting of sea otters during the 1700s and 1800s, it has been hypothesized that the Steller’s Sea Cow had been driven to extinction because the massive decline of sea otters caused the decline in kelp, which was caused by the overpopulation of sea urchins. Unfortunately, the steller’s sea cow relied heavily on kelp, but with all of it eaten by sea urchins, the steller’s sea cow didn’t have any other organism to feed off of so they became extinct (Estes, 2016). Not only does the decline in sea otters affect marine life, but they also affect land animals as well. The bald eagle has been struggling to find fish and baby sea otters to feed on ever since the decline in sea otters and this has caused them to find a new prey to feed on, but it hasn’t been as beneficial to them. Scientists have actually discovered that “the birds actually produced more eggs and young” due to the high caloric content of fish and baby sea otters when they had their original feeding plan (Shirley, 2008). This is just another one of the many organisms that will be inhibited if the sea otter population doesn’t increase in size soon. Additionally, sea otters have a great influence on kelp levels because they maintain the population of sea urchins and when left unchecked, urchins can destroy the entire kelp population.  This causes a major issue because kelp “absorbs and uses carbon dioxide in our water and atmosphere, potentially helping to reduce the effects of climate change” (Pepelko, 2013). When these kelp leaves fall off, they can remain at the bottom of the ocean floor for decades because they do not decompose. They actually continue with photosynthesis and it acts as another way to keep carbon sequestered under water instead of in the atmosphere. This is extremely helpful because climate change is continuously rising and we need everything we can to slow down its pace. It has also been assumed that kelp doesn’t contribute a vast chunk toward the amount of carbon in the earth’s atmosphere, but a study done by Jim Estes, a successful research biologist, proves that they do. Estes and his colleagues compared areas with lots of sea otters and areas with no sea otters for four decades, and the results were staggering. It was determined that “the presence of otters increased the carbon storage of kelp forests by 4.4 to 8.7 megatons which is equivalent to the amount of carbon found in the annual carbon dioxide emissions from three to six million passenger cars” (Cannon, 2012). This research shows that sea otters are indirectly responsible for “removing $205 million and $400 million worth of atmospheric carbon”. Based off of this study, sea otters have an undoubtedly large impact on climate change and if they were to vanish, then climate change will just speed up its process since there will be less kelp to remove CO2. In order to prevent this from occurring, the sea otter population must be increased even more so that their influence can help the kelp population to flourish. Not only will kelp be affected, but the viability of seaweed and eelgrass will have devastating effects as well if sea otters decline in population. The increase in sea urchin population comes with many severe consequences, but an equally great concern is the rise in the population of crabs. When the ecosystem is stable and the sea otter population is relatively high, the sea otters feed on crabs, which keeps the crab population from skyrocketing and this in turn maintains the population of sea slugs and shrimp. When the sea otters feed on crabs, it allows sea slugs and shrimp to not be eaten by the crabs, which allows them to clean off the algae on seaweed, keeping the water healthy and clear. One case study researched two different locations: one with sea otters and one without. The location with sea otters present had clear water, bundles of seaweed, and a relatively low population of crabs and sea urchins. On the other hand, the second location without sea otters, was a complete mess. There was very few bundles of kelp, the eelgrass was completely covered with algae which resulted in unclear water, and there were many crabs and sea urchins roaming the sea floor (Sea Otters Are Ecosystem Superheros, 2015). When the sea otter population decreases and causes the sea slug and shrimp population to decrease with it, the algae begins to build up and causes an algal bloom. An algal bloom is caused by the overgrowth of algae in the water that can produce dangerous toxins that can harm water and land organisms. It is very important to keep the water clean, otherwise the algae can create “dead zones” in the water which can kill any organism within the zone and can potentially harm land animals that are frequently by the water because the toxicity of the water (Agricultural Pollution, 2016). Sometimes, the toxins released by the algal bloom don’t affect organisms but they act as vectors, meaning that  they carry the toxin up the food chain to other higher level animals like seabirds, manatees, sea lions, and dolphins (Harmful Algal Bloom Impacts, 2014). Without sea otters indirectly affecting the amount of algae growth, a multitude of problems arise. Humans could unknowingly eat seafood full of harmful toxins within them and that would cause us to have to have medical treatments for both humans and animals, which would cost a fortune. Not to mention, we use seawater to convert to freshwater but if the water is full of toxins, it becomes more difficult to produce clean water. In order to prevent an algal bloom from causing many issues, the sea otter population  must be increase to its original population in the ecosystem so that they can minimize the population of crabs, which allow sea slugs and shrimp to take care of the algae. While sea otters are at risk from many predators, their population is actually significantly impacted by many human factors. Every day, we use products that rely on oil. It could be anywhere from filling up your vehicle with gas or using reusable plastic containers, but either way, we are supporting the drilling of oil. So when an oil spill occurs, that means that we have to take at least some of the blame because we have such a high demand for it. These oil spills cause many problems for marine wildlife, but it has caused the already low population of sea otters to decline even more when they occur.  In 1989, the Exxon Valdez oil spill in Alaska killed several thousand sea otters. It has also been discovered that 400 million gallons of oil spill into the oceans each year (Threats to Sea Otters, 2016). When the sea otters come into contact with the oil, this mattifies their fur and they cannot insulate their bodies correctly. Without being able to insulate themselves, they often die from hyperthermia because the water is so frigid. In order to reduce the amount of oil spills that take the lives of thousands of sea otters, we have to reduce our use of fossil fuels or prevent oil spillage in the first place. If everyone were to take part in cutting down  energy consumption by choosing public transportation every once in awhile, choosing energy efficient lighting, using solar power to generate energy, and driving an energy efficient car, then we could reduce the amount of oil that spills into the ocean each year (Your Choices Can Help, 2015). Also, you could politically support the use of clean energy instead of oil by joining organizations like the Sierra Club, the Center for American Progress, or even just volunteering your time to help the cause. It may not seem like these things would do very much, but if everyone were to join together and take these steps, then we could increase the sea otter population, as well as the majority of other marine life,  and bring the ecosystem away from disaster. The sea otter population is also declining because people are in direct conflict with sea otters. Many fishermen illegally shoot and entrap sea otters in nets, which poses a serious threat to the population of sea otters. Since sea otters pose as a competitor for fishermen because they eat the seafood they’re after, fishermen often kill sea otters or trap them in their nets, which causes them to drown. In order to solve this issue, there should be increased surveillance around fishing areas so that fishermen would be caught more easily when they trap the sea otters. Although, this is easier said than done. Even if we were to have increased maintenance, there would still be killings and that is why everyone, including fishermen, should be informed about the consequences of the decline of the sea otter population on the environment. That might steer people away from harming them. In California where many sea otters reside, parasites and infectious diseases make up 40% of sea otter death, which amounts to hundreds of sea otter deaths caused by humans (Threats to Sea Otters, 2016). This is caused when pollution on land runs off into the ocean and it contaminates the sea otter’s habitat. This can create harmful effects by jeopardizing their food sources or by making them sick because they cannot fight off the toxins present in the pollutants. What people don’t realize is that contamination of the ocean is caused by rain water because it doesn’t just soak into the ground. As it rains, water flows through lawns, driveways, and streets and then deposits the contaminants picked up by the water into the nearest waterway without being treated (Merten, 2011). This causes the water to actually warm up, and produces thermal pollution which is harmful to sea otters and many other ocean organisms. Some ways to combat this would be to plant a rain garden so the garden will collect the excess runoff instead of it going into the nearest water source, or create a yard waste compost, like grass clippings and leaves, so they don’t contaminate the water because they may contain pesticides and fertilizers, which should be limited as much as possible. It is also equally as important to not wash your car or anything in the driveway that involves soap because it runs into the waterway and is very detrimental to marine life’s health. If these little changes could be made, then we could increase the population of sea otters and help save the environment. It is important to realize that the population of sea otters affects our quality of life too, so it is very important to aid their rehabilitation in any way we can. Another way that we could help increase the sea otter population is to limit the use of fertilizers. When fertilizers runoff into the ocean from the rain, it creates a highly toxic environment and creates “dead zones” known as algal blooms. In 2010, it was discovered that sea otters were dying from microcystic poisoning, which is caused by fertilizers, and when researchers took samples of their environment, the results were shocking. Of the samples they took, they put organisms in them to see if they would survive and 55% of the organisms died in the samples taken (Agricultural Pollution, 2016). Our water shouldn’t be to the point where it kills the organisms that live in it and if we want to save the sea otters and the environment, then steps have to be taken in order to make sure fertilizers are not being used excessively. For this reason, there should be regulations on farms so they can only use a certain amount of fertilizer per square acre and to limit the amount of runoff, farmers could control where the water runs off to by digging ditches. This will certainly make a great impact on the lives of sea otters and many other ocean organisms, as well as the environment. Another great way to help sea otters is to donate money. There are many places to donate, like worldwildife.org where you can “adopt” a sea otter and you receive a stuffed animal sea otter and an adoption certificate or you can donate at the website otterproject.com. When you donate to these places, the money goes towards reintroducing sea otters into the wild so they have the ability to repopulate in certain areas where otters are scarce. The money is also used for keeping sea otters in zoos, like seaworld, where they rehabilitate them and give them the medications they need to become healthy once again and they also breed them so they can get their population to increase (Otters: Conservation and Research, (2015). It is important that people donate because without the help of the donors, then the sea otter population would continue to drop. It is also understood that not many people have the money to donate but there is an alternative to that. If you live in California or live in a state that has a sea otter fund and you pay income tax, you can quickly fill in a box to use your taxes for the sea otter fund. This way you’re not donating a ton of money and you get to help protect and improve the lives of sea otters. If the sea otter population doesn’t increase soon then an array of problems will appear. The sea urchin population will skyrocket which will cause the decline in kelp, which helps reduce climate change, but it will also screw up the entire food chain and other organisms will suffer from it. The crab population will also increase if the sea otters become extinct and that will cause unclear water and algal blooms, which are extremely toxic to the environment. The way to prevent this from happening is to prevent oil spills by not using as much oil, limiting runoff of contaminants and fertilizers, and to donate to a sea otter fund. While all of these reasons highlight the great importance and benefits of protecting sea otters, our impact shouldn’t be ignored. We are a great part of bringing back the sea otter population to what it was and we all need to work together to reduce the environmental hazards that we produce. By doing this, we will be able to save the sea otters and also create a healthier environment for ourselves as well.