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Fishing technology and rent dissipating. Anders Skonhoft Dep. of Economics NTNU. 1.Introduction. FAO statistics: 9% of the world fish stocks are depleted 18% overexploited 47% fully exploited 21% moderately exploited Average for the world. Much more dramatic in
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Fishing technology and rent dissipating Anders Skonhoft Dep. of Economics NTNU
1.Introduction • FAO statistics: • 9% of the world fish stocks are depleted • 18% overexploited • 47% fully exploited • 21% moderately exploited Average for the world. Much more dramatic in traditional fishing grounds (e.g. EU coastal waters)
Reasons • Institutional structure • Both within nations • External factors (straddling stocks, migration, etc.) • Valuable fish stocks • More valuable stock: always higher exploitation pressure • Highly efficient fishing technology
More efficient fishing technology • Individual beneficiary (at least in the short term) • Collectively disaster; depressed fish stocks as well as depressed profitability for the industry as a whole ??? • Short-term vs. long-term • Institutional structure of pivotal importance
In general: More efficient production, new products: The well-known riving forces behind increased material welfare. • Pioneering studies: Solow(1956), Abramovitz (1956): 75% of productivity growth due to technological improvement (TFP growth) • Confirmed by numerous later studies with much better data • Also sector studies, i.e., agriculture. • Much of the same picture, see, e.g., Hayami and Ruttan 1985
In what follows: • Technological change/efficiency improvement in a fishery. • Stylized model/reasoning within the institutional structure of ‘unregulated common property type’. In many fisheries (not at least in developing countries, and in large inland fisheries) still the prevailing management scheme • What happens when fishing technology becomes more efficient? Stock, harvest, rent… • What type of remedies?? • Changing institutional structure? • Input control?
2.Some evidence • Post-war period rapid progress in fishing technology • Larger boats • Better equipped • New synthetic materials • New finding equipment and techniques • Etc, etc…
Dramatic reduction in number of fishermen (in Norway and elsewhere) • Capital stock fluctuating… • Catch fluctuating • Total factor productivity growth (TFP) Norway: 0.8% per year (1961-2004) (Hannesson 2006) Correcting for lower fish stocks: Higher
But large problems with these calculations!! • But the broad picture clear
3.Technological change and the regulated fishery • Basic insight from the Gordon-Schaefer model (sole owner equilibrium fishery), or PV-rent maximizing (social planner model) of more efficient harvesting technology: • More effort use • Smaller stock (but no problems….Xmsy, or..) • Larger rent • So everything works well!! • More efficient technology is an unmixed bless
Gordon-Schäfer model TC TR Stock Xmey
4. The unregulated fishery • Many fisheries still exploited in an unregulated manner (remember: few regulations (at least quota setting) in any fisheries until the beginning of the 1980’s) • ‘Open-access’ model has served as a benchmark for many years (e.g., Gordon 1954, Homans and Wilen 1997). • Stylized model: Total rent dissipating. Means: zero-rent for an efficient as well as an inefficient technology. New capacity (vessels) flows in and out.
Here a more general approach: The fishermen are exploiting a fish stock in a myopic profit maximizing manner. • Myopic exploitation (…short sighted and neglecting the future…) and no value is imposed on the stock (zero shadow price) • Widely used exploitation scheme. Baland and Platteau (1996): ‘unregulated common property’. See also e.g., Bromley (1991). • Not only in fisheries; grazing exploitation (i.e., Saami reindeer herding), wildlife exploitation, etc. • Important feature: The number of fishermen (or capacity) fixed; local common, no entry), but lack of norms, regulations, etc.
Model: • Population growth • Catch function q ‘catchability coefficent’. Technology parameter (‘TFP’) • The fishermen aims to maximisze short-run profit
h: Contingent upon cost/price ratio, scale properties…and harvesting efficiency (q) • Non-linear first order difference equation. Possible oscillations and unstability, but harvesting stabilizes (cf. May 1976). • Possible expansion path:
What is going on here? • More efficient technology means smaller fish stock in the short-term as well as the long-term • More efficient technology yields highest rent in the short-term, but lowest in the long-term • The dynamic system will for realistic parameter values (intrinsic growth rate of the fish, etc.) settle down an equilibrium where total harvest=natural growth
Long-term equilibrium results: • Stock size, harvest,… and rent depending on harvesting efficiency (q)
Equilibrium rent and efficiency Rent Efficiency q
Improved technology/efficiency mixed bless!! It may increase as well dissipate the rent. • Remarkable result. Remember improved efficiency is assumed to be cost free (‘manna from heaven’). • The myopic nature of the fishery drives the result, but also externalities. The theory of the second best (Lipsey and Lancaster 1956)
Rent, efficiency and number of harvesters Rent n2>n1 n1 n2 Efficiency q
Rent, efficiency and value of harvest Rent p2>p1 p1 p2 Efficiency q
5. Conclusion • Simple model with stylized institutional structure • But holds in many instances. • Fisheries in developing countries • Open seas fisheries • Quasi-regulated fisheries (quota cheating, etc.) • Myopic exploitation instead of long-term considerations • Then new technology mixed bless! • New technology a possible disaster in the long-term.