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Tragedy of the Commons

Tragedy of the Commons

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Tragedy of the Commons

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  1. Tragedy of the Commons Fisheries: a case study

  2. Fishing • 1. How important is fishing to our global food supply? • 2. What kind of fishing is that? • 3. Whose fish are they, anyhow? • Fish are a common property resource • Fish are a renewable resource…. • What is that? • 4. How do we manage a common property to provide sustainable resource flow? • 5. How are we doing? (current status) • 6. What are the current issues? • 7. What is the good news?

  3. How important is fishing?

  4. World fish consumption is increasing

  5. Where do we catch it? Marine and Inland; Capture and Aquaculture

  6. Aquaculture now produces nearly half of all fish eaten today

  7. Fishing • 1. How important is fishing to our global food supply? • 2. What kind of fishing is that? • 3. Whose fish are they, anyhow? • Fish are a common property resource • Fish are a renewable resource…. • What is that? • 4. How do we manage a common property to provide sustainable resource flow? • 5. How are we doing? (current status) • 6. What are the current issues? • 7. What is the good news?

  8. Fish are a Renewable Resource • Living things that replenish themselves naturally and can be harvested, within limits (NMFS 2006). • Harvest is based upon the idea of “surplus production”: • Without us, fish at or near carrying capacity • Many young do not survive • With us, older fish removed: • Increases chance of younger fish survival • Results in younger, more dynamic population

  9. BUT: • Carrying capacity changes • Humans disturb habitat • Data are incomplete • Can Science truly provide all the answers? • HOLD THAT QUESTION!!!!

  10. Managing a Common Resource • Who owns fish? • They are a common resource • How do we manage common resources? • Class exercise.

  11. INSTRUCTIONS • Get into groups of 4. YOU MUST HAVE 4 IF AT ALL POSSIBLE. • Write your names on the data sheet • DO NOT TALK, AT ALL, NO COMMUNICATION OF ANY SORT WITH ONE ANOTHER. • There are fish in the lake. • You are each the head of a family. Your family needs at least 2 fish per week to survive. • You choose how many fish to take. You may take up to 4 fish. If you have more than 2, you may eventually sell them for a profit (but hold onto them for now). Keep the fish you catch in front of you (you may eat them later). • Take turns. As each person chooses, one of you write down on your data sheet how many fish were taken

  12. STILL NO TALKING!!!!! • After a complete circuit, • Write down how many fish are left at the end of the year. • you may now double the number of fish in the lake by taking the correct number from your second baggie (write this down under Year 2 starting fish) (this is reproduction) • We will do 5 full circuits

  13. On Carbonless paper, • Each of you quickly write the answer to questions 1 and 2 (put your name on the paper!) in your carbonless notebook. • Play a second game, BUT NO COMMUNICATING!!!! • Keep track of all the data. Answer questions 3 and 4.

  14. Finally: • Play a third game ...fill in your table again. • Talk together and make up new rules for fishing in your lake. Think about how you want to maintain a sustainable yield. • WRITE DOWN THE RULES IN YOUR CARBONLESS NOTEBOOK • Together write down answers to #3 and #4 on your datasheet.

  15. Let’s talk! Game 1 • 1. Did anyone in your group take too many fish?  How did that make you feel?  Did everyone try to take as many as possible?  Why or Why not?  Does society reward those with the “most”? • 2. Did anyone sacrifice the # of fish, for the good of the community?  Why or why not?  Does society ever reward that type of person?

  16. Game 2 • 3.       In Game two... how did your strategy change, if at all?  Does it make a difference to know what the rewards or consequences are? • 4.   Is it possible to maximize the number of fish caught/person AND the number of fish remaining in the pond at the same time? Why or Why not?

  17. Game 3 • What were your rules? • Did they work?

  18. Commons…. • Think of a local commons that you are familiar with. [parking lots, dorm social rooms, shared kitchens, bathrooms, bookstalls, etc.] Do similar situations arise? Explain. HOW might those problems be solved?  •   What are some natural resources that are common resources? •   What are the global commons?  Are these being used wisely?  Why or why not?

  19. How did your small communities do? (one member of group respond with clicker, please) For Game 1, end of ROUND 5, my group had: • 0-5 fish • 6-10 fish • 11-15 fish • More than 15 fish

  20. How did your small communities do? (one member of group respond with clicker, please) For Game 2, end of ROUND 5, my group had: • 0-5 fish • 6-10 fish • 11-15 fish • More than 15 fish

  21. How did your small communities do? (one member of group respond with clicker, please) For Game 3, end of ROUND 5, my group had: • 0-5 fish • 6-10 fish • 11-15 fish • More than 15 fish

  22. What made things get better? • 1. You experienced personal loss with environmental damage (you starved) • 2. You collected data, and responded accordingly…ADAPTIVE MANAGEMENT • 3. You were in a small community and you communicated to make rules that made sense.

  23. Fishing • http://news.bbc.co.uk/2/hi/science/nature/6033407.stm • ftp://ext-ftp.fao.org/video/2557-Fish-eng.mpeg • 1. How important is fishing to our global food supply? • 2. What kind of fishing is that? • 3. Whose fish are they, anyhow? • Fish are a renewable resource…. • What is that? • Fish are a common property resource • 4. How do we manage a common property to provide sustainable resource flow? (CLASS EXERCISE IMPORTANT!!!!) • 5. How are we doing? (current status) • 6. What are the current issues? • 7. Is there any good news?

  24. What’s so tragic? Tragedy of the Commons…your reading

  25. …”there is remarkable consistency in the history of resource exploitation: resources are inevitably overexploited, often to the point of collapse or extinction”. Luwig, Hilborn, and Walters 1993, Science

  26. Ludwig et al, continued • They go on to write that such consistency is due to common features such as: • Wealth or the prospect of wealth generates political and social power that is used to promote unlimited exploitation of resources; • Scientific understanding of large scale management is hampered by the need for replicates, controls, so that each problem demands new learning; • Large scale natural variability mask the effects of overexploitation until we reach the point at which the overexploitation is detectable AND irreversible.

  27. Fully Exploited Under + moderately exploited Overexploited or Depleted

  28. All we have left Nearly all the fisheries of the world are more than 50% fully or overexploited United Nations, FAO

  29. The surprise with North Atlantic codHigh range of variabilitycomplex interactionsOverexploitation

  30. What other environmental issues are there? (besides overexploited fisheries)

  31. Fish cross boundaries… • How do we protect at risk species that live in international waters? • CITES (the Convention on International Trade in Endangered Species of Wild Fauna and Flora) • CITES limits trade In threatened species….but is not ultimately successful….

  32. Pollution • Leading to reduced habitat • And toxic fish • Mercury • PCB’s • E.g. Salmon • 8 portions of wild Alaskan salmon per month • 1 of Chilean farm raised salmon…. • 1 of Norwegian farm raised salmon per 2 months • 1 from Scottish farm raised salmon every 4-5 months..

  33. Farmed salmon Wild salmon Supermarket salmon

  34. Governance and management of deep-water fisheries

  35. Yikes…what is the good news? • In small communities, one can find many positive examples of sustainable fisheries management. • What are the elements? • Experience and knowledge leading to good ideas..recognizing that environmental damage damages individuals. • Good Science and Good Data (monitoring and responding appropriately…”adaptive management”) • Communication among community members leading to mutually agreed upon goals and rules.

  36. And the challenge: • …”We might define sustainability as requiring that the average welfare of the successor generation, with respect to the total of all these values, be as high or higher than that of the current generation.” • (Kennedy (2003) article you read)

  37. Hope and a Challenge….(a quote from Kennedy) • Once we find agreement about what sustainability really means, we can ask what science might contribute. It is surely encouraging that science is focusing increasing attention on resource problems, but the success rate is not high. …At small scales, where science is applied in limited societies where property rights can be made clear, there have been some real winners, such as managed preserves that blend conservation objectives with recreational values. • … But at large scales, ranging from ocean fisheries to global climate, good science often fails the implementation test because the transaction costs are too high or because political and economic factors intervene. A recommended target stock size for managing a marine fishery fails, although its stability makes it desirable, because to harvesters it looks too large to leave alone. Models and climate history tell us that global warming is likely to reach damaging levels, but the cost of controlling carbon emissions is high and there is always the mirage of a hydrogen economy. • The big question in the end is not whether science can help. Plainly it could. Rather, it is whether scientific evidence can successfully overcome social, economic, and political resistance. That was Hardin’s big question 35 years ago, and it is now ours.

  38. http://www.eartheasy.com/eat_sustainable_seafoods.htm

  39. Last…. • Fisheries represent a potentially renewable resource! • The more people who understand, the more will there is to use the science and make decisions that support sustainability!