The introduction portion gives a brief explanation of what the Dead Zone is, how it’s caused, what it causes, and offers my hypothesis stating that this problem causes damage to the seafood industry that will worsen if it isn’t addressed. The research method consisted of reading through different scientific case studies found in the Academic Search Database to synthesize a conclusion of my own. The results covered 4 different case studies that focused on the effect of hypoxia in the shrimp market and the need for more field research/better measurements. The discussion portion includes the importance of why the Dead Zone still must be addressed even if there is a lack of correlation between it and the seafood industry. My research made me conclude that although the exact impact of the Dead Zone on the seafood industry is unclear, it’s still important to address the eutrophication and dead zone issue so that when research methods do improve, the impact isn’t worse than expected. I also concluded that the dead zone causes difficulties within the shrimp market.
Introduction:
I had never heard of the Gulf of Mexico Dead Zone until taking this class. Considering its massive size and the fact that there are other places in our oceans experiencing this same problem, I found it ridiculous that many ordinary people may not be aware of its existence, especially when humans are the main force in accelerating the factors contributing to the hypoxic zone. My goal for writing this report was to enlighten readers on this particular concern, how it could affect them, and why it’s important that it should be addressed.
There are a few things that readers must know before understanding this paper. The first is the definition of coastal hypoxia, which is characterized by low or depleted oxygen levels in water. It forms when high concentrations of nitrogen and phosphorus cause a significant growth of oxygen-consuming algae in offshore waters. The term given to this increase in the supply rate of organic matter is eutrophication, which alters the hydrologic cycle, temperature, salinity, nutrient concentrations, and stratification of the water column, and can lead to higher primary production. This may seem like a good thing, but the result of a sudden increase in production is more carbon fixation by living organisms who eventually die and sink down; when they sink, carbon sinks and oxygen depletes. This forms a dead zone. Within a dead zone, organisms are either forced to migrate as a primary response (Purcell, 3), or they die due to conditions that could not support life. This can impact food chains, considering that some levels of the trophic pyramid are capable of fleeing (like larger fish), while others are not (like phytoplankton and benthic communities). The death of large amounts of organisms and the movement of others affects their home habitat and causes other food webs/ecosystems to suffer because new species are coming in. The formation of a dead zone seems to produce a wide array of chaos due to anthropogenic causes.
The Gulf of Mexico Dead Zone’s formation is largely credited to the Mississippi River, which dumps about 1.6 million metric tons of nitrogen into the body of water annually (Joyce, 2). Depending on the conditions of the region, like temperature, the zone fluctuates and can reach the size of New Jersey.
Given the scope of the Gulf of Mexico Dead Zone and the effect that hypoxic conditions have on ocean ecosystems, I hypothesized that its existence causes significant harm to the seafood industry and those involved in it (fishermen, distributors, consumers).
Methods:
Study Area:
I decided to focus on 4 studies that discuss this topic. When I set out to do my research, I found consistency in my sources surrounding the shrimp market in the Gulf of Mexico. This is significant for researchers because, despite a large portion of shrimp being farmed globally, the Gulf still contains a significant shrimp fishery that contributes to the seafood market. I realized that this would only answer a specific aspect of my hypothesis. However, by focusing on shrimp, I was able to keep my results consistent with a specific market.
Data Analysis:
I analyzed my data by comparing the findings of each study I read in order to make my own conclusion. Some of the results varied, but there was an overall correlation in conclusions over the topic.
Results:
Study 1: Gulf of Mexico Hypoxia, aka, THE DEAD ZONE:
This source presented me with the idea of hypoxic conditions leading to trophic cascades, which can make fishermen's jobs harder. I came across the fact that fisheries are impacted by “direct mortality, forced migration, reduction in suitable habitat, increased susceptibility to predation, changes in food sources, and disruption of life cycles.” (Rabalais, 1). This aligns with the decreasing salinity in coastal marshes, loss of habitat, and increased fishing pressure. When hypoxia alters food webs by causing populations to change in size, commercial fisheries can be affected (see Figure #1).
Study 2: Gulf Shrimp Prices Reveal Hidden Economic Impact of Dead Zones.
The researchers in this study observed monthly trends in the price of Gulf brown shrimp from 1990 to 2010 and found that in hypoxic conditions, large shrimp prices spiked as fishermen put more effort into catching smaller shrimp. The tracking of this market is flawed, however, because fishermen often respond to changing conditions in the environment by moving locations. The link between hypoxia and economic loss in this study proved itself to be unclear because of this (Smith, 1).
Study 3: U.S. Shrimp Market Integration
The results of this case study yielded data similar to the last one. Observing the fluctuations in shrimp production since the 1990s, researchers confirmed that hypoxic conditions do have a negative impact on shrimp fisheries in the Gulf. However, due to the increase in imported shrimp and farming, it’s difficult to find a strong correlation between hypoxia and stress on the shrimp market. The study didn’t deny that hypoxia had the ability to influence prices before the 1990s, nor the fact that the fisheries in this region are affected by low oxygen conditions (Frank, 183).
Study 4: Hypoxia Effects on the spatial dynamics of the Northern Gulf of Mexico shrimp fishery
The data found in this case study presented that hypoxic conditions in the Gulf of Mexico can actually correlate with overfishing by increasing efforts into fisheries and altering the size distribution of caught shrimp. It also claims that fishermen's responses to hypoxic conditions produce skewed data and further complicate the following of the link between hypoxia and the shrimp market (Martin, 113). (Fig 2)
Discussion
The second and third studies that I reviewed presented me with the idea that researchers are struggling to properly measure this topic. They both acknowledged that hypoxic conditions in the Gulf of Mexico have harmful impacts, but it’s hard to track their correlation with the shrimp market because of the different variables involved with measuring (fishermen moving to new locations or catching alternative species). The first study claimed that hypoxia can alter trophic levels in ecosystems which can have an indirect correlation to the shrimp market due to making shrimp catch more difficult to achieve for people involved in the business. The fourth study also supported this idea and even claimed that the results of hypoxic conditions in ocean environments can lead to overfishing practices. Over-exploitation of shrimp can result in long-term harm to the Gulf ecosystem as well as the fishery market and everyone involved (fishermen, distributors, restaurant owners, consumers).
The overall view of this research comes off as skewed- because of flawed measuring practices and the relative newness of this issue. However, it’s safe to say that since the Gulf of Mexico Dead Zone causes substantial harm to organisms we catch and consume, it puts stress on fishermen to increase their efforts to travel to different locations and raise the prices of shrimp.
My hypothesis was partially supported by my data. I expected to find the impact of hypoxia on the entire seafood industry, however, I was able to find data on an important market within it. I expected to find clear data on how the Gulf dead zone causes almost direct harm to the shrimp market. Yet, due to a wide array of variables regarding the measurement of these effects, I now understand that researchers have a long way to go in determining the concrete correlation between the Gulf of Mexico Dead Zone and the well-being of the seafood industry. However, just because research on the dead zone’s economic impact is somewhat unclear does not mean that hypoxia in the gulf is not a serious issue. The dead zone still has a notable impact on the seafood and tourism industry, and it also continues to cause harm to local populations of species living in that area. Therefore, Americans must still take sustainable actions to prevent this phenomenon from worsening. These include government officials working with farmers to promote effective/efficient use of fertilizers to slow the eutrophication problem, as well as better filtering of excess nutrients from waters that travel to the Gulf.
Summary/Conclusion Points:
It’s important that economists and politicians understand the hypoxia issue so that they can accurately track the market value of nutrient pollution flowing into our oceans.
Although there isn’t a crystal clear correlation between the seafood industry’s well-being and the Gulf Dead Zone, actions should be taken to prevent the hypoxic conditions from persisting so that when measurement methods improve, the state of this particular market isn’t worse than we thought.
References:
Purcell, Kevin M., et al. “Fleet Behavior Is Responsive to a Large-Scale Environmental Disturbance: Hypoxia Effects on the Spatial Dynamics of the Northern Gulf of Mexico Shrimp Fishery.” PLoS ONE, vol. 12, no. 8, Aug. 2017, pp. 1–22. EBSCOhost, doi:10.1371/journal.pone.0183032.
Joyce, Stephanie. “The Dead Zones: Oxygen-Starved Coastal Waters.” Environmental Health Perspectives, vol. 108, no. 3, 2000, doi:10.2307/3454426.
Rabalais, Nancy N., et al. “Gulf of Mexico Hypoxia, A.K.A. ‘The Dead Zone.’” Annual Review of Ecology & Systematics, vol. 33, Dec. 2002, p. 235. EBSCOhost, doi:10.1146/annual. Ecol Syst.33.010802.150513.
“Gulf Shrimp Prices Reveal Hidden Economic Impact of Dead Zones.” Gulf Shrimp Prices Reveal Hidden Economic Impact of Dead Zones | Nicholas School of the Environment, 30 Jan. 2017, nicholas.duke.edu/about/news/gulf-shrimp-prices-reveal-hidden-economic-impact-dead-zones.
Asche, Frank, et al. “U.S. Shrimp Market Integration.” Marine Resource Economics, vol. 27, no. 2, Summer 2012, pp. 181–192. EBSCOhost, doi:10.5950/0738-1360-27.2.181.
Smith, Martin D., et al. “Spatial-Dynamics of Hypoxia and Fisheries: The Case of Gulf of Mexico Brown Shrimp.” Marine Resource Economics, vol. 29, no. 2, June 2014, pp. 111–131. EBSCOhost, doi:10.1086/676826.