Sustainable Use of Populations and Overexploitation


Sustainable use refers to exploiting a resource so that the resource is not depleted or permanently damaged. Sustainability is an internationally accepted minimal goal in managing biological resources. However, many populations are managed under more stringent goals, for example obtaining maximum sustainable biological or economic yield. Overexploitation refers to exploitation that is more intensive than such specific goals. While overexploitation is not sensible from societal point of view, in practice overexploitation often occurs because of the conflicting interests between individual exploiters and the public, and because individual exploiters often are maximizing short rather than longā€term benefits. When sustainable exploitation is attempted, significant practical challenges remain in determining particular exploitation levels that would guarantee chosen management goals. Good intentions may be ruined if uncertainty is not properly accounted for, and overexploitation may also result from lack of precaution.

Keywords: bioeconomics; exploitation; maximum sustainable yield; natural resource management

Figure 1.

(a) The relationships between exploitation effort, equilibrium population abundance and equilibrium yield in the logistic single‐species model. For too high effort, population goes extinct. The dependence between effort and yield is dome‐shaped, with the maximum sustainable yield (MSY) obtained in the middle. Sustainability declines with effort, but threshold beyond which exploitation is ‘unsustainable’ is a matter of debate. Similarly, the threshold for ‘overexploitation’ is a matter of debate. In this example, it is assumed that obtaining MSY is the management objective, and that effort levels that are higher than one giving MSY are considered biological overexploitation. Economic yield is usually maximized at a lower effort than biological yield. Consequently, economic overexploitation may be scored even when biological overexploitation is not yet occurring. While the detailed relationships depicted here depend on the model, the overall picture is model‐independent. (b) Dynamics of unexploited and exploited population in the logistic model. Unexploited population reaches carrying capacity (thick black curve). If exploitation is started, abundance declines. In the logistic model, intermediate effort (thick grey curve) gives the highest sustainable yield, but this also results in substantial reduction in equilibrium abundance. Notice that overexploitation (thin black curve) gives higher initial yield than exploiting with effort giving MSY.

Figure 2.

Number of species extinct or threatened by harvesting according to IUCN Red List. This includes hunting and gathering for food, medicine, fuel, material and cultural, scientific and leisure activities. No marine or freshwater plant species were listed. Data from the International Union for Conservation of Nature and Natural Resources (IUCN;, accessed in March 2008).

Figure 3.

State of the world marine fish stocks (FAO, ). FAO started monitoring the world's fish stocks in 1974, and categorizes them in different groups based on the level they have been exploited (see figure legend). The percentage of stocks ‘underexploited’ or ‘moderately harvested’ has decreased while the percentage of stocks ‘fully’ or ‘overexploited’ has increased. Underexploited and moderately exploited stocks could produce higher sustainable yields if exploited more, whereas fully exploited stocks are producing catches that are at or close to their maximum sustainable limits. Overexploited, depleted and recovering stocks are yielding less than their maximum potential owing to excess fishing pressure, with no possibilities in the short or medium term of further expansion. Reproduced from The State of World Fisheries and Aquaculture (2006), with permission from the Food and Agriculture Organization of the United Nations.



Carpenter SR, Brock WA and Ludwig D (2007) Appropriate discounting leads to forward‐looking ecosystem management. Ecological Research 22: 10–11.

Costanza R, d'Arge R, de Groot R et al. (1997) The value of the world's ecosystem services and natural capital. Nature 387: 253–260.

Dankel DJ, Skagen DW and Ulltang Ø (2008) Fisheries management in practice: review of 13 commercially important fish stocks. Reviews in Fish Biology and Fisheries 18: 201–233.

Diamond J (1997) Guns, Germs and Steel. A Short History of Everybody for the Last 13,000 Years. London: Vintage.

Food and Agriculture Organization of the United Nations (FAO) (2007) The State of World Fisheries and Aquaculture. Rome: FAO. (

Jennings S, Kaiser MJ and Reynolds JD (2001) Marine Fisheries Ecology. Malden, MA: Blackwell Publishing.

Jørgensen C, Enberg K, Dunlop ES et al. (2007) Managing evolving fish stocks. Science 318: 1247–1248.

Walters CJ, Christensen V, Martell SJ and Kitchell JF (2005) Possible ecosystem impacts of applying MSY policies from single‐species assessment. ICES Journal of Marine Science 62: 558–568.

Further Reading

Clark CW (1990) Mathematical Bioeconomics: The Optimal Management of Renewable Resources, 2nd edn. New York: Wiley.

Grafton RQ, Kompas T and Hilborn RW (2007) Economics of overexploitation revisited. Science 318: 1601.

Hardin G (1968) The tragedy of the commons. Science 162: 1243–1248.

Mace PM (2001) A new role for MSY in single‐species and ecosystem approaches to fisheries stock assessment and management. Fish and Fisheries 2: 2–32.

Reynolds JD, Mace GM, Redford KH and Robinson JG (eds.) (2001) Conservation of Exploited Species. Cambridge: Cambridge University Press.

The United Nations (1982) United Nations Convention on the Law of the Sea (

The United Nations (1992) Convention on Biological Diversity (

The United Nations (2002) Plan of Implementation of the World Summit on Sustainable Development. A/CONF.199/20, Chapter 1, Resolution 2, Johannesburg, September 2002 (http://www.un‐

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Heino, Mikko, and Enberg, Katja(Dec 2008) Sustainable Use of Populations and Overexploitation. In: eLS. John Wiley & Sons Ltd, Chichester. [doi: 10.1002/9780470015902.a0020476]