Title: Economics%20of%20Biotic%20Resources
1Economics of Biotic Resources
- Ecosystem Structure and Function
2Econ of Ecosystem Structure Renewable stock-flows
- Material flow from a stock over time
- Can use stock as fast as we want
- Level of stock affects future flow
3Sustainable Yield Curve
4Carrying capacity, MSY and minimum viable
population (point of critical depensation)
- Uncertainty and dependence on exogenous variables
- Variation in Critical depensation Passenger
pigeons and Mauritius Kestrel - Critical depensation for ecosystems
5Sustainable harvests and effort
What is the relationship to scale?
6Harvest effort and cost
- Yieldcatchability quotient x Stock x
effortYqXE - Stable equilibrium
- Unstable equilibrium
- Where did historical harvests take place?
- Where are they taking place now?
7Maximizing sustainable annual profit (static)
8Profit maximization
- p TR-TC
- maximum p occurs when MR MC
9Open access fishery
- Non-excludable, rival
- p 0
- This is what happens in any competitive market
- What happens when harvest costs are very low?
- What actually happens to harvest costs relative
to price over time?
10- Can you find the tacit assumption responsible for
the happy result that profit maximizing
exploitation does not require much stock
depletion?
11Profit maximization (dynamic)
- To move from one point on the sustainable
harvest curve to one at a lower stock, we must
reduce the stock. - What happens to the profit made by selling that
stock?
12Opportunity Costs of Renewable resources
- The opportunity cost of not harvesting is equal
to the foregone earnings from not investing the
profits of that harvest. - Whats more profitable, letting your redwoods
grow at 1 per year, or cutting them down and
investing the profits in the stock market at 7
per year?
13Opportunity Cost of Renewable resources
- The opportunity cost of harvesting another unit
of resource - Resource values should increase
- Increasing demand
- Decreasing supply
- Renewable resources grow, but a unit harvested
today cannot grow - More stock means cheaper harvest
14Dynamic profit Max
- Marginal opportunity costs of harvesting the
resource should equal marginal opportunity costs
of not harvesting the resource, i.e. MRMC - Think about repaying a loan with the profits from
reducing the stock - What if the discount rate is very high?
15Dynamic profit Max
16When is Extinction Optimal?
- Open access
- Private ownership, but resource cheap to harvest,
and grows more slowly than investments
17Including the fund-service
- Passenger pigeons
- Sardines
- Cassowaries
18Characteristics of optimal harvest
- Must account for stock-flow and fund service
- Discounting probably not appropriate, and
particularly inappropriate for fund-service
component - Higher stocks, lower harvests than static profit
maximizing stock and harvest - Must account for uncertainty
19Summary
20What is the relationship to distribution?
- Who benefits from ecosystem fund-services?
- Who benefits from the harvest of stock-flows?
- Who deserves profits from harvest of stock-flows?
21Natural dividend from renewable resources