Three Themes of Environmental Science

• How do natural systems function

• How have humans altered or damaged these natural systems

• How can we mitigate or repair the damage

Three Threads of Environmental Science

• Environmental/Ecological Functions

• Economic Impacts of Environmental Exploitation and Management

• Social/Cultural Impacts of Environmental Exploitation and Management

Tragedy of the Commons

What Happens When We All Share An Unregulated Resource?

AZ State Standards

• Concept 1: Changes in Environment

• Describe the interactions between human populations, natural hazards, and the environment.

• PO 1. Evaluate how the processes of natural ecosystems affect, and are affected by, humans.

• PO 3. Assess how human activities (e.g., clear cutting, water management, tree thinning) can affect the potential for hazards.

Content Objective

• SWBAT describe how the lack of central planning and regulation can result in the damage of commonly held resources.

• SWBAT provide an example of a commons they engage in that are in need of management.

Medieval Europe

• Livestock was wealth for peasants

• Cows > Sheep > Goats

“Commons” Are Unregulated Shared Resources

• In the 18th century, there were common pasturelands in Europe that many herders could jointly graze livestock in.

Thus, there was an incentive to have as many animals as possible on the land

Problem: Too many livestock would overgraze the grass, causing a food shortage to all of the farmers.

But, for the individual, the benefits of more livestock was large, while the damage was spread out evenly among all of the people.

It Creates the “Prisoner’s Dilemma”

• Do You Cooperate For the Greater Good?

• Or Do You Cheat For Your Own Benefit?

• There can be benefits to being selfish, but if everyone is selfish, you all lose!

Let’s Play A Game• You and a friend are caught by police for an armed

robbery

• They don’t have enough evidence to convict you of the break-in, but they can send you to jail for 1 year on a lesser charge of possession illegal firearms.

• So, they offer you a deal…

Prisoner’s Dilemma

• If you rat out your friend, and they stay silent, they get 20 years in jail and you go free.

• But, if you stay silent and they rat you out, you get 20 years in jail and they go free.

• If you both rat each other out, you both get 5 years.

• If you both stay silent, you

are both going to jail for 1 year

• What should you do?

Game Theory• If two people work together (refuse to testify),

you both benefit, as the worst they can do to you is 1 year.

• But, if one tries to cooperate, and you cheat (by ratting out the friend), the cooperator loses.

• However, if you both try to cheat, you both lose out over cooperating.

Let’s Play

• I will randomly choose two of you to be partners

• Write down if you will decide to stay silent or rat out your friend.

Grab an iPad and go to:

• kane.me.uk/ipd

• Play the game

• The person with the highest average score wins a prize.

• What strategy did you use?

Prisoner’s Dilemma

• In environmental science, there is a strong urge by individuals and companies to try and “cheat” the system and let everyone else pay for the environmental damage collectively.

• However, if everyone begins to “cheat”, then everyone loses…

The Tragedy of the Commons• In 1968, Garrett Hardin recognized that the

problems of the commons also applied to many other aspects of civilization.

Example of Tragedy of the CommonsResource depletion in an open market

The more cows you have, the more money you can make. But, you also need more acreage to feed those cows.

In the West, it takes about 3-4 acres of grazing land per cow. What if you don’t own enough land to make a living?

Example of Tragedy of the CommonsResource depletion in an open market

If you own more cows than your property can handle, then you will need to graze your cattle elsewhere part of the year to let the pasture recover or to grow hay for the winter.

But, that costs money… So, you have to decide on a strategy that gives you the best value.

An Overgrazed Pasture On Left

Tragedy of the CommonsResource depletion in an “free” market

U.S. Forest Service charges $1.69 per head/month to graze cattle in National Forests

Private pastures charge $15.10 per head/month on average out west

Which would you choose?

Grazing on Public Lands

• Not surprisingly, many ranchers across the west send their cattle out to public lands to graze.

• The benefit to the rancher is they can raise more cattle to sell.

• The costs, in this case to the landscape and contaminated water supplies, are spread out amongst all of the public, rather than the rancher’s own land.

What Are Some Other Examples of “Commons” That Exist Today?

• Write down with your partner commons in the environment…

The Air We Breathe?

The Water We Drink?

Public Spaces?

• We all suffer and pay for it when others choose to misuse the commons.

This is YOUR Commons!

Epic Journey of the Rubber Duckies and Nike Shoes

10,000 shipping containers are lost at sea every year!

1992• A container ship lost its load of 7,200 rubber

duckies on the way from Taiwan to Tacoma.

• Some started washing ashore about 6 months later

And 15 years later, the duckies were still washing up on the shore

It took 10 years for a shipment of 80,000 Nike shoes lost at sea to wash up on shore

500,000 shoes washed up in The Netherlands in 2006

But, That’s the Ocean…

• Olympic National Park must be a pristine place on land right?

Do You See That Brown Layer?

Hiking along in the Olympic Mountains on a beautiful summer day

The Smoke From Asia Can Travel Around the World

We Are All Interconnected

• 6,000 miles of open ocean does not stop garbage from floating to our wilderness shores.

• 6,000 miles of open air does not stop smoke and pollution from darkening our skies.

• What each of us chooses to do does matter to other people and to the ecosystems of the world.

So, Can Fishing Be a Tragedy of the Commons?

• You live in a small fishing village. You catch fish to feed your family and any extras can be sold at the local market.

Fisheries Simulation

M&M Fishing Activity• In each bowl, there are 30 mini and 10 mega M&Ms. Jumbo M&M’s

(tuna) provide 3x the income as regular M&M’s (tilapia).

• You will get 20 seconds to suck as many out with a straw as you can.

• You can not use your hands on the M&M’s or the straw.

• However many are left in the bowl, add an addition number equal to each for season 2 (and season 3).

• If you did not catch any, you drop out (die of starvation or leave village to look for work elsewhere).

Season 130 M 10 J

Mini Caught

Jumbo Caught

Mini Left

Jumbo Left

A

B

C

D

Season 2R J

Mini Caught

Jumbo Caught

Mini Left

Jumbo Left

A

B

C

D

Season 3R J

Mini Caught

Jumbo Caught

Mini Left

Jumbo Left

A

B

C

D

Fishing Seasons

The top two in each group from seasons 1 and 2 can now hold their straw with their hand. It is improved technology they were able to buy with their extra catch.

What Happened?• What happened to your family?

• What happened to your village?

Thought Questions

• What are some ways that this tragedy could have been avoided?

• How do you protect the good of the society from the demands of the individual?

Content Objective

• SWBAT describe how the lack of central planning and regulation can result in the damage of commonly held resources.

• SWBAT provide an example of a commons they engage in that are in need of management.