Tragedy of the Commons

“In every deliberation, we must consider the impact on the seventh generation….”
Great Law of the Iroquois

 

            “They know that they shouldn’t fish closer than 500 meters from the coast, but I’ve seen these boats with their nets out just 200 or 300 meters offshore. The officials don’t enforce the laws.”

We were visiting the Greek island of Mykonos while on tour with the Durango Choral Society. We walked along the harbor with our guide, David, admiring the many small fishing boats. He explained facets of the failing Greek economy as well as the ancient and modern sites on this beautiful island. The Aegean Sea around Mykonos was so overfished, David said, that there were few fish left to catch.

We found proof that David was correct when we sat down to eat. Restaurants, even those overlooking the beautiful blue Aegean, had menus that listed few seafood dishes. Any seafood was prohibitively expensive since it had been caught in distant seas.

The situation that we encountered in Greece is a good illustration of the “tragedy of the commons”. That tragedy can occur when a limited resource is open to uncontrolled use by many people. Any one user may think he can benefit from taking as much of the resource as possible. This behavior is rational only in the narrow sense of self-interest. Regrettably, unbridled use of a resource is likely to lead to its depletion.

The term “commons” referred to pastureland that was available for everyone to graze his sheep in old England. Now it includes many different vital resources such as the air we breathe, the water we drink and the fish in the Aegean.

Most of us learned to share in kindergarten. Unfortunately, some adults never mastered that lesson or have forgotten it.  When there are many people using the same resource, any person who takes more than his share may deprive others of their fair share. Even worse, selfish people can deplete the resource, so eventually no one benefits from it.

In the case of fishing off Mykonos, there had been plenty of seafood for centuries. In the past the boats and fishing techniques only allowed small, sustainable catches, so the small proportion of sea life that ended up in nets was quickly replaced. Now, with more fishermen and more effective fishing techniques and many more mouths to feed, the fish supply has been exhausted. The Greek government has tried to prevent depletion by having a “no fish” zone, with poor results. People don’t seem to pay attention to the law, or the reason that it is needed.

Human population growth is one factor leading to the tragedy of the commons: more people using the same resource means less for all.

Ironically, some of the pollutants we have unintentionally added to drinking water may serve as a feedback mechanism to slow human population growth. Endocrine disruptors are chemicals that have unintended hormonal effects. They are found in much of our country’s drinking water. Some come from insecticides and other agricultural chemicals. Many plastics contain BPA, which has undesirable effects. Another source is the waste of women taking hormones. These chemicals have been shown to produce fish and other animals with sexual aberrations. It is possible that endocrine disruptors will lead to decreased human fertility.

The amount of fresh water on the planet is limited and, in some cases, is very slow to be replenished. The Ogallala aquifer is an example of a resource that is being used in an unsustainable manner. Much of the food grown in our country’s midwestern breadbasket depends on water from this aquifer. Tragically, there are some places in eastern Colorado (and in other states) that rely on the Ogallala where the water table has dropped 40 feet in just 15 years!

As our human population has grown, the apparent size of the commons has shrunk. Although the first few wells in the Ogallala made little difference to the water table, now we seem to be sucking it dry. Dumping waste into a river or the atmosphere made little difference with few people and fewer factories, but these resources have become toxic in our populous, industrialized nation. We are learning the problems that can be caused by abusing the commons.

The people who will suffer the most may be those who come after us, the “seventh generation” in the Iroquois law. Unless we think and plan ahead, our progeny will not have the use of many of the resources that we have enjoyed.

© Richard Grossman MD, 2012