Dwindling Fish Supply

The world's supply of seafood, especially tuna, salmon and catfish, are quickly vanishing from the food chain. It has been projected that these marine creatures, as well as the other thousands of under-water species will be virtually spent by 2048 (4). Over fishing and pollution that has occurred within the last 20 years, has created a large imbalance within the ocean ecosystem.
Everyday, fisheries are working to provide the world with the necessary supply of fish. However, too many fishing companies have become involved in the hunt for marine life. The high demand for fish, especially in countries such as Japan, where fish is a main source of protein, has sparked an ever-increasing demand and value for fish. In recent decades, fishermen have found it difficult to meet quotas due to the growing number of exhausted fish.
As fish supplies become depleted, fishermen attack the water more intensely, taking their ships further away from land and into deeper waters in order to find the fish they desire (6). By the 1980s and 1990s all the world's waters had been touched by at least one fishery (6). The major problem with fish stock depletion involves the fishing and production habits of the individual fisheries and fishermen in the ocean. The ratio of fishing boats to fish for example is detrimentally uneven. The number of boats in the water vastly outweighs the number of fish. It makes it more difficult when many of the boats that depart from the docks today have highly technical and intense machinery that was developed for wartime marine operations. These devices have allowed the average fisheries to be at least 10 times more productive than 100 years ago (6).
According to a recent study, currently 80% of all marine fish stocks are fully exploited, over exploited, depleted, or recovering from depletion (5). Cod, hake, flounder, sole, and halibut were some of the first fish to suffer such reduction within the Northern Hemisphere (7). The depletion of these large fish has caused many ecological problems that will significantly impact the way we all live.

As the fish continue to deplete from the world's waters, the effects of their movement toward extinction has become more apparent.
One example of the marine problems we face sits within the food chain. These large fish feed on smaller fish, such as sardines, herring and anchovies, which feed on microscopic bug-like creatures in the water. Those tiny bug organisms survive off of the algae in the water. As the large fish disappear, the small fish that they feed on become more abundantly in supply. When there is an abundance of small fish, like anchovies, the bug-like microorganisms are eaten and suffer a similar depletion issue as the large fish. These bugs help to monitor the algae supply in the water and without that; there is excess algae pollution throughout the ocean (6).

Another problem has been the excess supply of jellyfish in the ocean. In the past, humans rarely consumed jellyfish, a creature often eaten by the larger carnivorous fish. With the depletion of the larger fish, however, there has been an outburst of jellyfish in the waters. Because jellyfish also feed on the eggs of larger fish, they have helped hinder the reproduction and re-establishment rates of the desired fish in the ocean. The utilization of jellyfish, in moderation, is beneficial for the ecosystem because the mass quantities of jellyfish in the sea has made them more sustainable and appealing to more consumers. Certain types of jellyfish are currently growing in consumption popularity in East Asia and parts of China (6).

There is competition for the fish stocks among different animal societies. Penguins, for example, are one species that is greatly suffering from human consumption of fish, especially the overfishing of anchovetta (10). This specific overfishing has caused a population decline of the Humboldt penguin (10). Another animal that is equally affected by human overfishing is the Russian Brown bear (11). Without fish such as trout, salmon, anchovetta, etc. many creatures that rely on these fish are suffering from population decline, and are being forced to adjust their eating habits in order to survive.

1) NPR: Talk of the Nation. Tuna: A Favorite Fish Faces Dangerous Depletion. September 05, 2009
2) NPR: Morning Edition. EU Faces Off with Fishers over Blue Fin Tuna. July 15, 2008.
3) Management Blamed for Depletion of Fish. The Washington Post. Juliet Eilperin. June 27, 2004
4) World's Fish Supply Running Out, Researchers Warn. The Washington Post. Juliet Eilperin. November 3, 2006.
5) Depletion of Prey Fish may be Starving the Oceans. ENN: Environmental News Network. April 7, 2009
6) NPR: Fresh Air. The Perils of Overfishing Part 1 and Part 2. November 2, 2009
7) Aquacalypse Now: The End of Fish. The New Republic. Daniel Pauly. September 28, 2009.
8) http://www.montereybayaquarium.org/cr/cr_seafoodwatch/sfw_health.aspx
9) http://www.mcbi.org/what/shiftinggears.htm
10) http://www.seaworld.org/infobooks/penguins/longevity.html
11) http://peer.tamu.edu/curriculum_modules/Ecosystems/module_4/whatweknow4.htm