The Chesapeake Bay oyster population has been in decline for over a century. The oyster population now is less than 1% of the historical population of oysters in the bay. To put this into perspective, watermen used to harvest 20 million bushels of oysters compared to the 200,000 bushels they are harvesting today. A bushel of oysters is a basket filled of oysters. Oysters are a very important species to the Chesapeake Bay. The oysters help clean the water. They filter and decontaminate the water through their shells. As shown in the diagram below, oysters have a few more benefits on the ecosystem other than cleaning the water. The ecosystem can also be harmful to the oysters which can lead to a decrease in the population. There are four main reasons for the decline in the oyster's population: overfishing, habitat destruction, water quality, and disease.
OverfishingOysters have been overfished since watermen started to harvest them. Overfishing is the main cause of the decline. Taking too many oysters out of the water and not leaving enough to reproduce for the next harvest season is what leads to a decline in population. This can lead to habitat destruction which can cause water quality to turn for the worse. Then, the bad water quality can cause the diseases. It is a chain reaction from overfishing which causes a decline in the population.
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Habitat DestructionOysters are harvested by either a dredge or tongs. Dredging is when a boat pulls the dredge across the floor of the bay as the dredge scraps the bottom for oysters. Habitat destruction is caused by over dredging and using tongs on and around the oyster reefs. This can cause reefs to die out because there aren’t enough oysters present. This will lead to the water quality to become less filtered and more polluted.
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Water Quality |
Diseases |
As the oyster population decreased significantly, it “must have changed the ‘ecology’ of the Chesapeake Bay”. These changes caused the total filtration rate of oysters to decline. The water quality in the bay started to become worse. The water quality become bad because of two reasons. The first reason was that the oyster population wasn't as plentiful, so the water wasn't being filter as much as it was and it started to become more polluted. The other reason is that the pollution coming from the tributaries of the bay started to cover the oyster reefs with silk. The oysters couldn't clean the water fast enough and the silk ended up covering the reefs.
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The diseases are caused because of the water quality. There have been three different diseases that attacked the oyster’s population since 1945. The first disease happened from 1950 to 1955 was called the First Dermo Outbreak. Dermo is a single celled parasite which can end up killing the oyster. The second disease was from 1960 to 1972 and was called the MSX Epidemic. The most recent one was from 1987 to 2005 called the Dermo Epidemic. It was the most powerful disease and took out most of the oyster population during the time period.
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The three stakeholders are the three groups of people most important to the issue. The watermen, Department of Natural Resources (DNR), and the consumers are the most important groups of people in this issue. The watermen are the people who harvest the oysters. The DNR regulates the laws and regulations on harvesting the oysters. The consumers are the people who buy the oysters from the watermen and the people who eat the oysters.
Photos From:
https://www.minnpost.com/earth-journal/2012/04/global-warming-hurts-oysters-carbon-cost-reading-newsprint
https://estuarychesapeake.wordpress.com/tag/oysters-2/
http://seafood.maryland.gov/gear-types/
https://www.minnpost.com/earth-journal/2012/04/global-warming-hurts-oysters-carbon-cost-reading-newsprint
https://estuarychesapeake.wordpress.com/tag/oysters-2/
http://seafood.maryland.gov/gear-types/