Abstract
Previous research proposes that human beings are motivated to protect endangered species for various reasons: consumptive use value, non-consumptive use value, non-use value, and intrinsic value. However, it has been difficult to tease apart these values at the behavioral level. Using an innovative fishing game, we study an important tradeoff between one kind of use value (monetary value) and one kind of non-use value (existence value) of the endangered Steller sea lion. In the fishing game, players make repeated decisions on how much pollock to harvest for profit in each period in a dynamic ecosystem. The population of the endangered sea lion depends on the population of pollock, which in turn depends on the harvesting behavior of humans. The data show that in general, people responded to the financial value (as a tourist resource), but not the existence value, of the sea lion by cutting down commercial fish harvesting to keep more sea lions in the ecosystem. However, not all people behaved the same regarding the existence value. Females displayed a higher existence value than males, as did people who reported stronger pro-environmental attitudes than those with weaker pro-environmental attitudes. Our findings have multiple implications on public opinion elicitation and public policy design.
Similar content being viewed by others
Notes
The profit is increasing in both the harvest level and the population of pollock so that the players will not deplete the stock in the last period. In addition the formulation chosen is concave in H, showing diminishing returns to within-period harvesting.
References
Allman ES, Rhodes JA (2004) Mathematical models in biology: an introduction. Cambridge University Press, Cambridge
Barbier EB, Burgess JC, Folke C (1994) Paradise lost? The ecological economics of biodiversity. Earthscan Publications, London
Barbier EB (2011) Pricing nature. Ann Rev Resour Econ 3:337–353
Callicot JB (2006) Explicit and implicit values. In: Scott JM, Goble DD, Davis FW (eds) The endangered species act at thirty: conserving biodiversity in human-dominated landscapes, 2nd edn. Island Press, Washington
Daily GC (1997) Nature’s services: societal dependence on ecosystem services. Island Press, Washington
Dunlap RE, LiereKD Van (2000) Measuring endorsement of the new ecological paradigm: a revised NEP scale. J Soc Issues 56(3):425–442
European Commission (2007) Attitudes of Europeans towards the issue of biodiversity. In: Flash Eurobarometer Report no. 219. Gallup Organization. http://ec.europa.eu/public_opinion/flash/fl_290_en.pdf. Cited 27 Feb 2012
Finnoff D, Tschirhart JT (2003) Harvesting in an eight-species ecosystem. J Environ Econ Manag 45:589–611
Finnoff D, GongM Tschirhart JT (2012) Perspectives on ecosystem based management for delivering ecosystem services with an example from an eighteen-species marine mode. Int Rev Environ Resour Econ 6(1): 79–118
Freeman AM (2003) The measurement of environmental and resource values: theory and methods, 2nd edn. Resources for the Future, Washington
Gifford R, Hay R, Boros K (1982) Individual differences in environmental attitudes. J Environ Educ 14:19–23
Gong M, Aadland D (2011) Interview effects in an environmental valuation telephone survey. Environ Resour Econ 49(1):47–64
Heal GM (2000) Nature and the marketplace. Island Press, Washington
Hunter LM, Johnson A, Hatch A (2004) Cross-national gender variation in environmental behaviors. Soc Sci Q 85(3):677–694
Naeem S, Li S (1997) Biodiversity enhances ecosystem reliability. Nature 390:507–509
Rasinski KA, Smith TW, Zuckerbraun S (1994) Fairness motivations and tradeoffs underlying public support for government environmental spending in nine nations. J Soc Issues 50:179–197
Rausser G, Small A (2000) Valuing research leads: bioprospecting and the conservation of genetic resources. J Polit Econ 108(1):173–206
Simpson D, Sedjo R, Reid J (1996) Valuing biodiversity for use in pharmaceuticalresearch. J Polit Econ 104(1):163–185
Swanson TM, Barbier EB (eds) (1992) Economics for the wilds: wildlife, wildlands, diversity and development. Earthscan Publications, London
Tilman D, Lehman CL, Bristow CE (1998) Diversity-stability relationships: statistical inevitability or ecological consequence. Am Nat 151:277–282
Zelezny LC, Chua P-P, Aldrich C (2000) Elaborating on gender differences in environmentalism. J Soc Issues 56:443–457
Acknowledgments
We wish to thank Ian Bateman and an anonymous review for their feedback on an earlier version of the paper. We appreciate helpful comments and suggestions from Edward B. Barbier, Jonathan Baron, Howard Kunreuther, David H. Krantz, Sabine Max, Ben Orlove, Elke U. Weber and participants at the CRED lab meetings and Altisource research seminars. We thank Columbia Business School Behavior Lab, Matthew Sisco, and Liang Wang for collecting and compiling the data. Major funding was provided under the cooperative agreement NSFSES-0951516 awarded to the Center for Research on Environmental Decisions.
Author information
Authors and Affiliations
Corresponding author
Appendices
Appendix 1: List of 17 Largest Conservation Organizations
This list is meant to consist of the largest organizations devoted to biodiversity. The criterion for size of organization, was reporting annual revenue of more than $2 million. In some instances, environmental problems other than biodiversity are focused on as well by these groups, but biodiversity is a prime focus for all organizations included.
This list was compiled by first scanning through the initial 10 pages of both Yahoo and Google search responses to “protect endangered species” and “protect biodiversity.” Second, several informal online lists, as well as directory services such as Charity Navigator, were looked over to find any relevant organizations that the initial search may have missed.
The list includes (in order of size):
-
1
The Nature Conservancy
-
2
Wildlife Conservation Society
-
3
World Wildlife Fund
-
4
The Royal Society for the Protection of Birds
-
5
National Wildlife Federation
-
6
International Union for Conservation of Nature
-
7
Conservation International
-
8
National Audubon Society
-
9
Defenders of Wildlife
-
10
African Wildlife Foundation
-
11
Oceana
-
12
Center for Biological Diversity
-
13
EcoHealth Alliance
-
14
Amazon Conservation Team
-
15
Fauna and Flora International
-
16
National Wildlife Refuge Association
-
17
World Land Trust—US
Appendix 2: Instructions
In this study, you will play a fisherman’s game. As a fisherman in the Eastern Bering Sea, you have to make a decision on how much Pollock you will harvest in each period. The following maps show the location of the Eastern Bering Sea.
Each period, you earn units of an experimental currency called Talers by harvesting the Pollock. The game always lasts 10 periods. The Talers you earn in each period accumulate over time, and will determine your final payoff. 10,000 Talers are exchangeable for $1. To illustrate, suppose at the end of the game, Participant 3 has 80,000 Talers and Participant 5 has 40,000 Talers. Participant 3 will be paid $8 (80,000 Talers)\( \,\,+\,\, \)$6 fee\( \,\,=\,\, \)$14. Participant 5 will be paid $4 (40,000 Talers)\( \,\,+\,\, \)$6 fee \(\,=\,\) $10.
Figure 4 presents an ecosystem map of your territory. There are 13 species in your fishing area. Arrows indicate predator-prey relationships. As shown in the map, Pollock preys on zooplankton, and is food to several marine mammals. For example, Pollock accounts for 45 % of a sea lion’s diet. In each period, the population of sea lions is approximately half of the population of Pollock.
The Pollock population in the first period is 250 units. The growth of the Pollock in each period depends on both the current population of the Pollock and on that of its predator, sea lion. In general, the higher the Pollock population is, and the lower the sea lion population is, the faster the growth of the Pollock will be. But because the ecosystem has limited resource to sustain the Pollock growth, when the Pollock population is too high, the growth rate may slow down.
In period t, the Pollock’s population equals to its population in the previous period (Period (t\(-\)1))\(+\) Growth in Period (t\(-\)1))—your harvest in Period (t\(-\)1)). For example, suppose that the pollock population in Period 2 is 200, the growth is 19, the harvest is 30, then the population of Pollock in Period 3 \(=\) population of Pollock in Period 2 \(+\) growth in Period 2—harvest in Period 2 \(=\) 200 \(+\) 19\(-\)30\(\,=\,\)189.
The sea lion’s population depends on that of its prey, the Pollock. The higher the Pollock population is, the higher the sen lion’s population.
The mathematical growth formula of Pollock is presented in the “Appendix”, if you are interested in the details.
In each period, the current status of the ecosystem will be presented on the screen, as shown on the next page. You will then make a decision on how much Pollock to harvest. Your profit depends on both how much you harvest and how large the Pollock population is: Profit = Harvest \(\times \) (Population\(-\)Harvest). For example, if you harvest H units of Pollock in the 4th period, and the Pollock population in that period is 180 units, then your profit in the 4th period is H \(\times \) (180\(-\)H) Talers.
To play the game, you will need to complete a few quiz questions. After the quiz, you will see the following decision page. You need to click the harvest cell, then hit ENTER to put in your desired harvest amount. To prevent accidental harvesting, in each period, you need to click SUBMIT at the bottom of the decision page to submit your harvest. That is, there are 3 steps: (1) type the amount in the harvest cell; (2) enter the number in the cell by hitting ENTER; (3) submit the number by clicking SUBMIT.
You can practice with the game before playing it for real to better understand how harvest impacts Pollock population, and how the ecosystem responds to your harvests. The current practice can be restarted anytime you click “Restart Practice.” If you would like to quit practice and play the game for real, please click “Exit Practice”. The Exit icon works only after you have completed the practice game at least once. Note that if you exit the practice mode and play the game for real, you cannot go back to the practice mode.
Please raise your hand if you have any question. Otherwise, please click Quiz to start the game.
1.1 The Growth Function of Pollock
Mathematically, the growth of Pollock follows the function below:
where
For example, suppose that the pollock population in Period 2 is 200, the population of sealion in Period 2 is \(10 \times \root 2 \of {200}=141\), the growth of Pollock in Period 2 is \(100 \times 200 \times (1 - \frac{200}{300})/141 = 19.\)
Suppose you harvest 30 in period 2, then the Pollock population in Period 3 \(=\) population of Pollock in Period 2 \(+\) growth in Period 2—harvest in Period \(2 = 200+19-30 = 189\).
Appendix 3
Appendix 4
Appendix 5
Appendix 6
Appendix 7
Rights and permissions
About this article
Cite this article
Gong, M., Heal, G. Why do People Care about Sea Lions? A Fishing Game to Study the Value of Endangered Species. Environ Resource Econ 59, 503–523 (2014). https://doi.org/10.1007/s10640-013-9746-8
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10640-013-9746-8