Sprol

Photo credit: Armando Estudiante via Creative Commons

A tragedy of the commons is a type of social trap that involves a conflict over resources between an individual’s interests and that of the common good. In this situation, a group of people work toward short-term individual gains, which, in the end, leads to a loss for the group as a whole.
Tragedy of the commons originated from a parable published in 1833 by William Forster Lloyd. The theory itself, however, dates back to Aristotle who said:

“That which is common to the greatest number has the least care bestowed upon it.”

Aristotle knew what he was talking about and one great example of this is the overfishing of our oceans, which has been increasing dramatically over the last 50 years as advances in fishing technology have been made.

In years gone by, it was common to see trawlers and fishing boats at the many ports around the country, and world. These boats, however, have been replaced by vast fishing ships that are capable of being at sea for weeks on end. These factory ships come with all the bells and whisles needed to preserve each day’s catch, which means that these efficient ships need to return to port only when their holds are full of fish.

As is the case with many advances in technology, the birth of the factory fishing ships brought about some devasting changes to the commercial fishing industry. While there was an initial seven percent increase in the number of catches each year during the 50s and 60s, there has been a steady decline in the size of the fish in each catch.

Additionally, roughly 20 of the planet’s smaller, but once prolific fisheries have vanished over the last 25 years. Many more fisheries are having serious trouble staying afloat and may not recover from this overfishing catastrophy.

As can be expected, technology found a way around the ever-decreasing size of the fish being caught in the indiscriminate trawler nets. Smaller mesh is being used, which allows much smaller fish, and other sealife, to be trapped. Because a lot of these smallfry are just that — too small — to be used as human seafood, many are crushed or minced and, ultimately, used as fertilizer or animal food.

As mentioned, net fishing is very indiscriminate, unlike a seasoned fisherman who knows what to keep and what to return to the sea to be allowed to grow into a real keeper. Today, just about any sea-living creatures, big or small, can get trapped in these new super nets.

It has been estimated that with every ton of prawns (or shrimp) caught, roughly three tons of other fish are caught, killed and discarded. Another estimated 20,000 porpoises die every year in the Atlantic and Pacific oceans in nets intended for salmon and tens of thousands of dolphins are killed yearly by the tuna-fishing industry.

Photo credit: Merkur Nallbani via Creative Commons

It is necessary to mention that many types of commercially-caught fish have been harvested so feverishly around the globe that a once seemingly endless supply is now threatened on global levels. In fact, some research says there is reason to believe that the commercial fishing industry has actually prompted a change in the gene pool of several species of fish. If this is true, these fish are much less likely to thrive and may not be able to bounce back from the overfishing.

A study at Stony Brook University in New York focused on six generations of a small anchovy-like fish. Striking evolutionary changes were noted. The latter generations of fish turned out to be smaller, were less interesting in foraging for their food and produced fewer viable eggs.
Although this study was conducted in a laboratory setting, the findings could help explain an odd occurrence that has had fishermen and scientists perplexed for years. Even after overfishing has been halted, the population of many fish species simply do not bounce back to their previous numbers.

It appears that, as the larger fish are removed from the species’ gene pool, future populations get a little smaller with each passing year. The larger fish may be caught prior to mating, therefore, their stronger, healthier genes are lost leaving the smaller fish to replenish the depleted population.
The findings of the Stony Brook study challenges the assumption that if a few million fish are left in the ocean, even after overfishing has taken place, there will be enough for a given species of fish to restock itself. This assumption is further challenged by another study conducted by researchers at the University of Washington.

The researchers focused on and studied a population of New Zealand snapper, which had been depleted to around three million remaining fish. They assumed that three million would be enough to allow the population to replenish itself; however, what they found was quite different.
The scientists discovered that only one in 10,000 fish was still capable of mating. This meant that the genetic diversity of the entire snapper population depended on just a few hundred fish. Consequently, a reduction in a species’ diversity leaves the remaining population much more susceptible to environmental factors and pollutants, and it makes them less able to survive or repopulate the species.

If these studies are correct, it would seem logical that longer periods of reduced or completely-halted fishing would be required for the successful repopulation of overfished species.

Nature’s ability of restoring depleted fish populations is also dependent on whether the oceanic ecosystems are still capable of supporting an increased number of certain species of fish. Drastic alterations in the makeup of different species’ populations might possibly create new equilibrium energy flows which actually start to involve other species.

This ecosystem shift can have startling effects. For example, if virtually all the trout are eliminated from a certain area, the carp will most likely take over. If this happens, it will be impossible for the trout to re-establish a successful mating population.

Photo credit: Atanas Entchev via Creative Commons

Because of global overfishing, trawlers must seek their catch in deeper waters, which is threatening the delicate deep-sea ecosystem and the much diverse marine life that calls these areas home. Look at the coelacanths, which are closely related to lungfishes. These amazing fish were believed to have been extinct since the end of the Cretaceous period. However, in 1938, a healthy, live specimen was caught off the east coast of South Africa.

What will happen to species, such as the coelacanths, if overfishing continues at the current rate?

While much factors into the problem of overfishing, one thing is sure. Ask just about any avid sea fisherman and they will confirm that the fish are smaller now than they used to be. With the whoppers being caught before they ever reach their spawning grounds, it may take many generations before the true kings-of-the-sea return. Hopefully, they will return.

With the help of such organizations as the Marine Stewardship Council (MSC), an independent organization committed to finding a solution to the overfishing crisis, maybe there is still hope.
The MSC was founded in 1997 and has developed an environmental standard for sustaining and managing today’s oceanic fisheries. They reward environmentally responsible fisheries with the use of their blue product ecolabel. Consumers concerned about overfishing are now able to purchase seafood that has been independently scrutinized against MSC’s standards.
Since this past January, 22 fisheries, nationally and internationally, have been evaluated and granted certification for meeting MSC’s environmental standards.

Today, there are roughly 500 seafood products being sold in 25 countries around the plant that meet these standards. This may seem like only a drop-in-the-bucket; however, many times environmental improvement begins as a small effort but ends up making huge, positive progress that benefits the common good.