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Optimal harvesting, economic discounting and extinction risk in fluctuating populations

Abstract

DETERMINISTIC models demonstrate that when the economic dis-count rate of future harvests exceeds a critical value related to population growth rate, the strategy that maximizes the present value of cumulative harvest is immediate extinction (liquidation) of the population1–3. Here we analyse stochastic models to derive optimal strategies that maximize the expected present value of cumulative harvest before extinction of a fluctuating population. Stochastic models reveal that discount rates below the critical value can substantially reduce the mean time to extinction and the expected real harvest before extinction. With an unstable equilib-rium at small population size (Allee effect4–6 or depensation2), the critical discount rate is lower in the stochastic model than in the corresponding deterministic model. These results argue against economic discounting in the development of optimal strategies for sustainable use of biological resources.

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References

  1. Clark, C. W. Science 181, 630–634 (1973).

    Article  ADS  CAS  Google Scholar 

  2. Clark, C. W. Mathematical Bioeconomics 2nd edn (Wiley, New York, 1990).

    MATH  Google Scholar 

  3. May, R. M. Nature 263, 91–92 (1976).

    Article  ADS  Google Scholar 

  4. Allee, W. C., Emerson, A. E., Park, O., Park, T. & Schmidt, K. P. Principles of Animal Ecology (Saunders, Philadelphia, 1949).

    Google Scholar 

  5. Fowler, C. W. & Baker, J. D. Rept International Whaling Commission 41, 545–554 (1991).

    Google Scholar 

  6. Dennis, B. Natural Resource Modeling 3, 481–538 (1989).

    Article  MathSciNet  Google Scholar 

  7. Ludwig, D., Hilborn, R. & Walters, C. Science 260, 17, 36 (1993).

    Article  ADS  CAS  Google Scholar 

  8. Redford, K. H. BioScience 42, 412–422 (1992).

    Article  Google Scholar 

  9. Primack, R. B. Essentials of Conservation Biology (Sinauer, Sunderland. MA. 1993).

    Google Scholar 

  10. Goombridge, B. (ed.) Global Biodiversity: Status of the Earth's Living Resources (Chapman & Hall, New York, 1992).

  11. Cumming, D. H. M., Du Toit, R. F. & Stuart, S. N. African Elephants and Rhinos. Status Survey and Conservation Action Plans (International Union for the Conservation of Nature and Natural Resources, Gland, Switzerland, 1990).

    Google Scholar 

  12. Miller, G. T. Jr Living in the Environment. An Introduction to Environmental Science 6th edn (Wadsworth, Belmont, CA, 1990).

    Google Scholar 

  13. Le Boeuf, B. in The Natural History of An̄o Nuevo (eds Le Boeuf, B. & Kaza, S.) Ch. 7. 287–325 (Boxwood, Pacific Grove, CA. 1981).

    Google Scholar 

  14. Halliday, T. Vanishing Birds: Their Natural History and Conservation (Penguin, Harmonds-worth, 1980).

    Google Scholar 

  15. Van Valen, L. Evol. Theory 1, 1–30 (1973).

    Google Scholar 

  16. Jablonski, D. Science 231, 129–133 (1986).

    Article  ADS  CAS  Google Scholar 

  17. Beddington, J. R. & May, R. M. Science 197, 463–465 (1977).

    Article  ADS  CAS  Google Scholar 

  18. May, R. M., Beddington, J. R., Horwood, J. W. & Shepherd, J. G. Math. Biosci. 42, 219–252 (1978).

    Article  MathSciNet  Google Scholar 

  19. Reed, W. J. Math. Biosci. 41, 273–307 (1978).

    Article  MathSciNet  Google Scholar 

  20. Karlin, S. & Taylor, H. M. A Second Course in Stochastic Processes (Academic, New York, 1981).

    MATH  Google Scholar 

  21. Lande, R., Engen, S. & Saether, B.-E. Am. Nat. (in the press).

  22. Daley, H. E. & Cobb, J. B. Jr For the Common Good. Redirecting the Economy Toward Community, the Environment, and a Sustainable Future (Beacon, Boston, 1989).

    Google Scholar 

  23. Keller, H. B. Numerical Methods for Two-Point Boundary Value Problems (Blaisdale, New York, 1968).

    MATH  Google Scholar 

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Lande, R., Engen, S. & Saether, BE. Optimal harvesting, economic discounting and extinction risk in fluctuating populations. Nature 372, 88–90 (1994). https://doi.org/10.1038/372088a0

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