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Cort Hammond

I was shocked by the second image on CNN’s slideshow that documented the March 14th dead zone that formed in Lagoa Rodrigo de Freitas. It is estimated that over 65 tons of fish died as a result of organic nutrient-rich run-off during a rainstorm that increased BOD and lead to a hypoxic event. The worst event occurred in 2000 when 100 tons of fish died. This clearly demonstrates the interconnectivity of the land and bodies of water. These hypoxic events are seasonal and have been occurring since the 1980s, which indicates that they result from urbanization. Using a quick land use analysis program, I estimated that around 40%-50% of the area around the lake is urban. While this is a high number, it doesn’t account for the severe dead zones.
Interestingly runoff problems are difficult to solve with economic incentives since stormwater systems are controlled by the city and situations can be unique. Therefore, it is likely that a non-market valuation of the lake would be most effective in improving public policy. If cities were aware of the future costs of restoring lakes, then better drainage systems could be installed. Indeed, a policy shift has driven the local sanitation company to revise the areas drainage system. Furthermore, attempts have been made to restore mangroves and increase the natural water flow from the sea.
I don’t doubt that more work could be done to value lakes and provide a non-market cost associated with anthropogenic hypoxic events.

Curtis Jay Correll

It seems from this article that the situation in the oceans may be even worse than that on land. Even worse than that, it seems that they will contribute to each other. When the coral reefs subside, the barrier against coastal storms will be less effective. With more coastal storms, natural habitats will be destroyed, and the economy will be hurt too. In the same way, pollution on land can cause acid rain, which pollutes the ocean more. This makes for a nasty cycle of destruction for the environment.
The picture with all the dying fish is amazing to me. Images like that need to be distributed to the voting public, and it needs to be made known that this is not an isolated event but something that will become ever more common in the future. If we continue on our current path, all of the predictions from this article and more will mess up our environment and our future. That cannot be allowed to happen, so we must find a way to stop it. The environmentalists who focus on marine biology must team up with other environmentalists as well as the media and economists. Only then can big business lose its hold on the public and stop further destruction of our world.

Holley Beasley

I like how Levitt begins introducing the issue by stating that the ocean is the forgotten world on Earth. He continues on how ridiculous that is, considering oceans make up 90% of the living volume on this planet, but it is absolutely true. It is also not entirely the public's fault, because opportunities to experience and interact with the ocean are limited, especially to those who live far away. Even for those who live close, most encounters include nothing more than just a walk in the sand or a quick dip in the water. It is estimated that less than five percent of the human population have had the opportunity to scuba dive and experience the wonders of the ocean. The rest of the population relies on pictures or videos to understand what exists under the ocean's surface. We always talk about how hard it is to put a value on things like air quality and water quality, but those are things everyone experiences on a daily basis. The quality of the oceans and marine life is an even more intangible value, and it is even harder to put a number value on something that most people have never even encountered.

With that being said, those who have encountered and experienced the wonders of the ocean need to be held even more responsible. It can't be left up to policy makers who haven't even ever experienced ocean life to make a change. As Curtis said, the destruction of the oceans and the pollution on land make for a nasty cycle of destruction, and images of the dead fish need to be just as prevalent in public media as images of Beijing's air quality.

Julia Seelye

This article highlights how few people comprehend the severity of the consequences of overfishing and, perhaps more importantly, how little is actually being done to ameliorate the current crisis by those who are cognizant of the threats to our oceans. Harvesting methods like bottom-trawling are egregiously destructive to marine life and have long-lasting, disastrous effects on the world's interconnected oceanic ecosystems. The author makes a particularly poignant comparison of fishermen bottom-trawling to farmers plowing a field of wildflowers just because they can. Because the practice is so devastating, there is only one course of action: banning bottom-trawling entirely. Unlike other threats to our oceans that have more ambiguous roots - oxygenation, acidification, global warming - bottom-trawling's specific impact makes it more likely that raising public and political awareness could put pressure on lawmakers to increase regulation of fishing practices. As others have pointed out, our oceans are clearly in trouble, but a lack of recognition and comprehension of the problems hinders political progress that would mitigate some of those issues.

Nathan Plein

The most important part of this article in my opinion is the real lack of public and political awareness of these issues, especially overfishing. As someone who has lived by the ocean my whole life, I was aware of the the problems stemming for polluting the ocean, yet I had never of overfishing being a threat. However the last couple weeks of class and this article have shown me that overfishing might be the single biggest threat to the marine ecosystem. This lack of awareness is a problem because without the politicians being aware of the issue or the public calling for change nothing will happen. This also relates to the point made above by Holly that most people don't ever have significant experiences or interactions with the ocean. Without having these experiences it is hard for people to appreciate or understand the value of the marine ecosystem. With all of the other environmental issues our planet is facing right now, this is an issue that could go easily go overlooked because it does not hit close enough to home for most people.

Avery Gant

As the case with some of the posters above, the first few images on CNN were a little shocking. While the article sets a grim tone, the pictures (mainly # 2 & 9) really illustrate the severity of the strain that is currently being placed on populations of fish. The situation appears to be a perfect illustration of the tragedy of the commons; the current system appears to be obviously broken and is not sustainable. Individuals are all so eager to gain a benefit from harvesting the fish that are available to them that they have driven the populations of fisheries into the ground (or seafloor I guess...). A good solution to the problem could be to place limitations on the number of fishermen allowed to harvest fish. Doing so could give these populations a little wiggle room to recover and reach sustainable levels. I am a little skeptical of the effectiveness of this practice, especially if there is no enforcement agency constantly policing the actions of local fishermen in these areas. With bottom-up trawling being used, local fishermen are to catch such vast amounts fish very quickly. Will enforcement agencies actually be able to police these entire preserves? If they cannot, I do not believe this practice will begin to sufficiently slow the rate of oceanic ecosystem degradation.

Hampton Ike

CNN provides a bleak view for the future vitality of not only the ocean environment, but also the impacts that will reverberate throughout the global community. I was not aware of the severity of overfishing worldwide to the extent that it was discussed by CNN. A key component to the overfishing and destructive fishing methods has to do with the countries involved and governmental irresponsibility with regards to legislating or enforcing renewable fishing methods. The larger more affluent European nations should have no excuse for poor fishing methods or over-harvesting, and should foster renewable fishing techniques in countries with limited governmental control or care over environmental degradation with respect to the ocean. It is very disheartening in particular when the article mentioned a recently discover coral reef that will likely die before the end of this decade. The developing and undereducated nations cannot be the only ones to blame for the overfishing and harmful techniques, and the developed nations need to become more involved due to the interconnected nature of all things in the ocean. However, the developed nations must be held accountable for the oceanic degradation caused by direct runoff and pollution as well as increased global carbon levels in the air leading to ocean sequestration and eventual acidification. This article raises the concerns of oceanic degradation across many different areas, and the end result is a laundry list of nations and governments to blame. The true response to these problems involves regional as well as large scale governmental involvement in fishing practices, harvest quotas, greenhouse gas pollution, and source pollution to name just a few.

Rachel Samuels

As one of the humans that do venture into the oceans, they are a constant source of wonder and beauty for me. For those that have never been 60 ft under, however, their diversity and complex ecosystems are often forgotten. The agriculture of the sea is fishing, and, unlike with pesticide controls and land use laws, there is really no good way to regulate the over-exploitation of the oceans. The massacre of the corals and the decimation of so many different fish populations is horrendous, and I am glad that CNN wrote an article and displayed it regarding the atrocities committed against aquatic life, but moral suasion alone is highly unlikely to help with anything beyond awareness. There need to be global laws regarding fishing mechanisms, as the oceans are the greatest example of a tragedy of the commons. The carbonic acid increase in the oceans can be traced to CO2 emissions, and any headway on global warming should help in that regard, but the death of so many fish populations and the corals must be addressed directly. Bottom trawling does not have a high yield when compared with seine nets (though the alternative the article provided, long-line fishing, has an even lower yield). Evolving technology will not help in terms of overfishing certain species, but it will help with decreasing by-catch, endangered or not. In terms of detrimental fishing practices, there needs to be a global moratorium on bottom trawling, and other possiblities offered. Perhaps there also need to be subsidies of direct fish products and taxes against commercial fishing; regardless, we are going to ruin our oceans without having even explored their potential further if we continue as we are.

I must add, however, that I found it odd how precise the article claimed to be in terms of its species estimation (1 million in the ocean) when in fact so little is known about the ocean (it's probably more). Also, the article claimed a third of all CO2 was absorbed by the ocean, but the article it linked to clearly stated a fourth. I completely agree with what the article was saying, but some of its figures and statistics seemed vague guesstimates at best and self-contradictory at worst.

Jonathan Stutts

I feel obligated to echo some of Rachel's concerns (above). It's hard for me to believe that we truly comprehend all of what is going on in the ocean. It's also hard for me to believe that we can have such drastic effects on a body so massive. I get the acidity story more than I buy the idea that we could bottom-trawl our way to starvation. Regardless, my main takeaway, and primary fear, is that we will take longer to act than our resources can last. In the past, our earth changed much slower than our decision making process. Today, I'm not so sure we aren't in the opposite situation

Shawn Swaney

The fisheries population is literally in shambles. At this point, we have overfished it to the point where many species are unable to rebound. While it all seems good and well to stop fishing, how many of us are actually going to stop buying that sushi, find that pack of tuna with the sustainable catch logo, the list goes on. Because we can not directly census populations of fish like we can with terrestrial species, we have no direct sense of how massively we are impacting the populations.

Being a Biology major that wants to go into management of fisheries and species conservation, this issue hits home for me pretty hard. Unless we take drastic measures very soon, the fisheries system as we know it will die. Even though we have a grim future in the open water, sustainable actions like farm fishing and aquaculture allow for a slow shift away from unsustainable practices. There is a lot of promising legislation in the works, but until this issue comes into every single home's decision-making, it won't do much good

Tim Werner

After reading this article, I find it unbelievable that a method like bottom-trawling exists and has not been banned when all of its negative effects are considered. I cannot imagine what percentage of that catch is actually brought to the market and not just killed and thrown back into the ocean. I will not go much further into that since Hampton addressed a lot of those points about fishing methods above.

More alarming to me in this article was the profound effect of pollution on the ocean’s acidity, and as a result, the effect it will have on the marine-food chain and the existence of coral. The article really put into perspective how fortunate I am to have seen the Great Barrier Reef; it upsets me to read about its imminent death. Furthermore, I am disheartened to read in this article about another reef discovered in Norway only a short time ago that will be dead before 2020 at this rate.

After reading Callum Roberts quote before the end of this article, I would like to know how extreme the regulations (cutback on fishing, waste, etc.) they would need to implement to protect the oceans due to the fact that “most of the world’s ocean is located outside of international law and legal control.” Therefore, they would be forced to regulate these standards in areas that are under international law and legal control. Meanwhile, if people, commercial fishermen for example, wanted to continue the bad practices, they could move into the non-regulated waters.

Scott Diamond

In this article Levitt provides an overview of the two significant threats to our oceans and their inhabitants: ocean acidification and over-fishing. Besides housing some of the most complex ecosystems on the planet, the ocean sequesters nearly one third of all human carbon emissions. As a result, the acidity of the world’s oceans have increased by nearly 30% in the last 150 years. Additionally, fishers commonly employ trawling to capture fish, an especially destructive and inefficient fishing method. Fishing practices have resulted in the deaths of nearly one million turtles and the depletion of numerous populations of fish.
Before reading this article, I was only acutely aware of these issues and their magnitude. Ocean acidification seems to be just another negative effect of our carbon emission, and could likely be ameliorated with many of the methods we discussed in class to curb emissions. There seems to be even less public awareness about the dangers of over fishing, but there does seem to be evidence that this is changing. WholeFoods, the specialty food store, in conjunction with the Marine Stewardship Council has maintained its commitment to educating other grocers about the dangers of sustainability. WholeFoods was the first grocer to own its own fisheries and set sustainability contracts with fishers, and now actively spreads the message that retailers can be wildly profitable while being socially responsible. Despite these actions, there is a long road ahead in educating the public about these grave and pervasive issues.

Dylan Florig

After reading this article, I was shocked just at the number of factors that are damaging our oceans. It truly seems that we are in a catastrophic situation. If we fix only our fishing issues, there will still be pollution, acidity, and global warming threats. The line mentioned briefly in the article about heading toward an "end game" really caught my attention. It seems that in the coming future the only way to fish will be in privately managed fisheries. I don't know what effect this would have on fish as a human food source, but it is obvious that we would lose the marine biodiversity that makes our oceans so intriguing and valuable. As others have mentioned, it can be tough to get people to appreciate what is going on under the sea since much of it is not tangible, nor have many had direct exposure to the oceans. Even if the U.S. takes action on the issue of fishing, other countries that do not will continue to destroy the ocean, and ultimately the U.S. would just be at a disadvantage as a result of our decision, a scenario that sounds much like the global climate change problem. However, trying to convince fishermen or people in third world countries that they need to cut back on fishing seems like it will be a tough task to achieve. The future of our oceans certainly seems bleak to me now that I've read this article and discussed it in class.

Charles Busch

This article brings to light many of the current and future anthropogenic threats to ocean ecosystems. Not only are many species being over-harvested at an unsustainable rate, but we are destroying their habitats which will affect their future reproduction prospects. In class, we looked at the parabolic reproduction curves of ocean species. It follows from the model that as we over-harvest fish and other ocean creatures, we reduce their populations which can be seen as a backwards movement along the curve. However, to the extent that we impair ocean ecosystems, we are actually probably further reducing ocean species' reproductive capacity by shifting the curve down. Examples in the article such as ocean acidification, coral reef destruction, water pollution, and "trawling" are both reducing populations in the short term, and inhibiting the ability of ocean species to reproduce in the future. In particular, I was taken aback at the huge increase in the acidity of oceans due to CO2 being dissolved into the water. When I think about greenhouse gases,I typically think about air pollution, global temperature increases, etc. but I do not think about our oceans absorbing these gases on a massive scale. Clearly, this is just another reason to reduce CO2 emissions in order to preserve our ocean ecosystems for future generations.

Wen Xiang Chuah

The article serves to highlight the shortfalls in traditional methods of thinking about marine resources. As we increasingly come up against the maximum holding capacity of the planet, it is crucial to examine our core assumptions regarding the sustainability of our activities, especially in light of the chronic human fallacy of short termism. In particular, the article highlights the effects that the unseen (marine) ecosystem has on our lifestyle, especially with regards to carbon dioxide absorption. Again, like with other issues that we've examined this winter, much of the regulation for a global public good such as this will have to originate from a central unified source, as no one nation is sufficient to combat the threat posed by manmade externalities to the natural world.

Will Andrews

It is also interesting to note that the adverse effect of humans on the ocean documented in the article are only the observed effects. The ocean is so vast and hard to observe that it is very possible that there are more unobserved negative effect of over fishing, climate change, and pollution. It seems that the two worlds, land and ocean, are often thought of as separate, but it is important to consider the interrelation between though two when at the very least humans' adverse effect on the worlds are at topic of conversation. The fact that the remoteness of the ocean has not protected it from humans should certainly bold face the problem we are causing in the way we use the world and its resources.

Katja Kleine

I agree with the point brought up by many, including Will: The ocean is just so big we really don’t understand the full impact of what humans have done to change the oceans. That is a particularly scary thought given the fact that we have already done so much that we can visibly and physically account for. I think that one of the main purposes of the article, was that it highlighted the need for more international legislation on what we do and do not allow in the world’s oceans. Although it would be difficult to get full participation and just all around be a difficult process, it may be a worthwhile and necessary endeavor. Without stricter restrictions, like banning bottom-trawling how can we stop overfishing? We can also relate this to the Environmental Justice issue that many of the people who are suffering most are those in poor coastal communities who rely on fishing for the protein source and livelihood.

Tyler Voorhees

This article brings up some of the many anthropogenic threats to the ocean, but also shows how little we really understand about those affects. It also touches on the theme Laura Henson’s talk. Laura was inspired to continue her career path thanks to diving with relatively well-known species, but the article emphasizes how little is known to the general public about some of the little known and smaller species. We need more people like Laura and the marine biologists quoted in this article that are able to articulate the importance of some of these species and the dire situation they are in.
This article was also a little disheartening because it touched on the interlocking affects that other climate problems are having on the health of ocean ecosystems. Clearly, global warming will continue to play a big role in the health of the ocean, but the health of the ocean will also play a big role in climate change, and both will have impacts on human populations that require the ocean for protein. It would be interesting to know how limiting fishing could affect land use and if regulations aimed at protecting the oceans might just cause use to use more land for farming, thus continuing to other problems on land.

Julia Murray

While I, like many others, was shocked by the severity of overfishing and the and the effects of climate change and pollution on the ocean, I am not that surprised that it is harder to raise awareness about environmental problems of the ocean. First of all, as the article points out, no part of the ocean belongs to any specific country, and it is therefore not in any one country's direct economic interest to take action. This problem is a classic tragedy of the commons, but it is perhaps even worse because most people do not live near or even see the ocean on a regular basis, so they do not see this problem affecting them at all. While climate change on land will physically manifest in changing weather patterns and differences to the majority of the world's everyday lives, overfishing and ocean acidification do not directly affect most people.

Additionally, as we discussed in class last week, people are much more likely to want to help animals that have human characteristics--animals with big eyes like owls or dogs. Fish look absolutely nothing like humans. They have small eyes, scales and are mostly viewed only as a source of food. While there is certainly a population of people that care about the well-being of fish, this population is not large compared to the rest of the world. In order to raise awareness about this issue, it may be necessary to frame it by how it will change human life: diminishing choices of edible fish, fewer recreational opportunities, etc.

Paul R

We have discussed this problem of over fishing in class often. I did not know about the dredging technique of fishing. The fact that 90percent of the catch in these nets is thrown back seems incredibly inefficient. Even if the net caught coral; people eat coral and could gain some benefit from the capture. This process is destructive but in class the marginal damage function isn't set at 0 for maximum efficiency. Some damages occur and are accepted by society when all costs and damages are known.

PEOPLE WANT MORE TURTLES! Sea grass provide good nurseries for baby sea turtles. One way to get Asian countries to not use techniques that harm sea turtles is to provide incentives and infrastructure for tourism and diving.

Unfortunately, simply outlawing fishing hurts most low income/impoverished people. If they are worried about providing basic needs like food and shelter for their families they will fish. Governments could provide incentives to protect fish species or to fish in a more sustainable manner.

Brett Murray

Although some of the statistics from this article are staggering, I still do not think that people fully understand the magnitude of the implications and consequences that are associated with such staggering statistics. For example, the fact that 90% of all predatory (big) fish have been killed represents a serious threat to the availability of future fisheries. This 90% of large fish is not a statistic that can be suddenly fixed by starting to protect these species. The diverse and abundant range of species resulted from ecological and biological processes over the course of millions and millions of years, so the remaining 90% reduction in total population represents an example of a population bottleneck (when a population's size is reduced for more than one generation). The following quote describes the substantial implications of population bottlenecks:

"Reduced genetic variation means that the population may not be able to adapt to new selection pressures, such as climatic change or a shift in available resources, because the genetic variation that selection would act on may have already drifted out of the population"

In essence, these fisheries will only become even more susceptible to abrupt environmental and climatic changes. I had never heard of trawling practices until this article, which seems ridiculous that such practices are still being employed today. Ultimately, I really enjoyed this article because it discusses a few of the complexities that very few people seem to be aware of at this point in time. I am also interested in learning more about the topic of ocean acidification. I have read about this topic before but was not aware that it was such a pressing issue. The overall theme of this article is that there has to be a push to raise social and political awareness on the serious threats to our global fisheries before it is too late. Irreparable damage has already occured, so it is time that we start confronting these challenges as opposed to delaying efforts to protect and restore global fisheries to a sustainable level.

Gyung Jeong

It is true that deep below the ocean surface is a place where humans have rarely ventured. However, it is also true what Professor O’Dor said, “The disturbing truth is that humans are having unrecognized impacts on every part of the ocean, and there is much we have not seen that will disappear before we ever get a chance.” This lack of awareness of this issue makes the situation even worse. To be honest, all kinds of climate changes, over fishing, acid rain, etc., are caused by humans, but we are not really trying to improve our ecosystem. As the article suggests, bottom-trawling is the worst over fishing method. It basically catches most of the fish from the sea, including over one million sea turtles. I am not saying fishing is bad. What I am saying here is that we should not fish for more than what we need. If it’s possible, we should just fish enough so that we can eat enough, without damaging the fish population. Also, lack of public awareness of these issues is a big problem. People have to know and understand the situations because all these negative impacts will come back and hurt us.

Sommer Ireland

The visuals alone that CNN posted should be enough to convince the average joe that we truly are doing something terrible to our oceans, and that in the long run humans are decimating their own greatest source of protein. As CNN reported, the biggest problem is that most of the ocean is outside of international law and legal control. And unfortunately, laws and enforcement of those laws are the only ways to stop the harm to our oceans. I completely agree that trawling needs to be outlawed. Sure it may be quicker, but the damage done and the unnecessary sea life that is killed in the process does not make it worth it. If it can't be outlawed then it needs to be severely taxed. As someone who lives on the coast, I know that fishing and shrimping are people's livelihoods, which is why they have the incentive to catch as much as they can to sell. And that's the problem, it becomes somewhat of a race. If neighbors Bob and Joe are both fishermen, Bob's going to catch the absolute maximum that he can because he knows that if he doesn't, his neighbor Joe will. And this is just discussing the fish, not even the coral reefs that fall prey to the destructive fishing techniques. Coral reefs as we have learned, are the most diverse ecosystems on the planet host to countless numbers of different ocean species. But with these habitats being destroyed, the sea life that calls the reefs their homes are becoming homeless, vulnerable to predators, and in a lot of cases are setting themselves up to become endangered if they aren't already.
There needs to be an international solution to this problem. And that solution needs to be compatible for developing nations since they are the most dependent on fish as their main source of protein (if they are located near the ocean). We can't' tell nations or people that they can't fish, obviously that wouldn't do anything. But we can try and place restrictions on how people fish, and try to promote sustainable fishing so that we aren't' driving species to extinction.

Matthew Thomas Howell

I am surprised by the inefficiency of the current fishing methods. The fact that 90% of the catch gets returned to the ocean is ridiculous. I wonder how fisherman can continue to sustain themselves using such an inefficient method. The article also made me connect to today's lecture about option values. The ocean is largely unexplored and unknown to humans, yet we are scraping it clean of all life. While changes in air composition is linked with many damages and consequent effects, changes in ocean temperature, acidity, and composition could have a multitude of unknown effects upon our environment.


This article by Tom Levitt addresses one of the most pressing and widespread threats to biodiversity and ecological integrity: the global-scale overharvesting and depletion of fish species for human consumption. East Asian countries are commonly blamed for these devastating declines in oceanic fish species because fish serve as the primary source of food, due to relatively low costs and (historically) high availability. While it’s easy to point the finger at these countries, they are by no means the only reason for the worldwide fisheries collapse we are currently witnessing. Archaic fishing techniques, such as bottom-trawling and dredging, are also largely do blame for the decline of fish species, not because theses techniques necessarily remove more fish than other techniques, but because the methods they employ cause serious destruction of benthic/coral habitats, regions essential to the ecological integrity of oceans due to primary productivity. Dredging and bottom-trawling are also inefficient fishing techniques because they collect large amount of bycatch, sometime up to 90%. This results in a substantial environmental externality, as “bycatch” fish often die while struggling to escape the net or are so exhausted from the struggle that they are rendered defenseless to prey once they are thrown back into the ocean. Athropogenically-fueled global warming is also to blame for decline in fish species because water acidifies as temperatures rise. This most negatively affects the world’s coral reefs, often viewed as the foundation of ocean ecosystems due to their habitat heterogeneity and biological diversity. One of the most difficult problems facing global fisheries management is the issue of legal control in international/disputed waters. Many fisheries occur in international waters, and are thus difficult to regulate because no one country has the legal right to control fishing regulations. The result is the classic case of the tragedy of the commons. To prevent the global-scale collapse of fisheries, the international community must establish strict, cooperative fishing regulations where stakeholders are incentivized to harvest less fish and punish those who do not follow regulations.

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