Basharat A.K. Pitafi

Prevention, Eradication, and Containment of Invasive Species: Illustrations from Hawaii

Invasive species change ecosystems and the economic services such ecosystems provide. Optimal policy will minimize the expected damages and costs of prevention and control. We seek to explain policy outcomes as a function of biological and economic factors, using the case of Hawaii to illustrate. First, we consider an existing invader, Miconia calvescens, a plant with the potential to reduce biodiversity, soil cover, and water availability. We then examine an imminent threat, the potential arrival of the Brown treesnake (Boiga irregularis). The arrival of the snake in Guam has led to native bird extirpations, power outages, and health costs.

Pareto-Improving Water Management over Space and Time: The Honolulu Case

Proposals for marginal cost water pricing have often been found to be politically infeasible because current users will have to pay a higher price even though future users will be better off. We show how efficiency pricing can be rendered Pareto-improving, and thus politically feasible, by compensating the users suffering a loss due to higher prices. We also provide a method for determining efficient spatial and inter-temporal water management for a system with consumption at significantly different elevations supplied from a renewable coastal aquifer, which is subject to salinity if over-extracted.

The Economic Value Of Watershed Conservation

Watershed conservation creates benefi ts within and beyond the management area of interest. The magnitude of the benefi ts also depends considerably on economic policies accompanying conservation measures. Direct benefi ts come from biodiversity protection, improved recharge, and the improved quality of ground and surface water. Additionally, the health of a watershed has profound implications on near-shore resources, including beaches and coral reefs. In the case of the Koolau Watershed on the island of Oahu, Hawaii, total economic benefi ts are found to be well above costs. The anticipated cost of watershed conservation into the indefi nite future has a present value of

Free-Range Farming and the Optimal Public and Private Responses to a Possible Epidemic

43.2 million using a discount rate of 1%. The benefi ts of watershed conservation stemming from groundwater recharge alone vary widely depending on the assessment of increased recharge but may be more than

Some Resource Economics of Invasive Species

900 million provided that conservation is accompanied by pricing reform. Benefi ts to near-shore resources (including the avoidance of beach closures and reef sedimentation) range from

Pareto-Improving Water Management over Space and Time

4.2 million to

EVALUATING INTERDEPENDENT WATERSHED CONSERVATION AND GROUND WATER MANAGEMENT REFORMS1

22.0 million even before accounting for fl ood and sewage-spill damages in March, 2006.

Impatience and Intergenerational Equity in a Model of Sustainable Growth

We develop an optimizing model of a farm that is subject to invasion by an infectious disease such as bird flu, where the probability of invasion depends on the degree of free-ranging on the farm and post-invasion rate of spread on the farm depends on the farm size, the farmers surveillance efforts, and the degree of free-ranging. We examine optimal policies for the farm and for the government, and analyze how these policies are affected by the degree of free-ranging. We find, inter alia, that when the farm size is endogenous fining an infected farm is superior as an instrument than providing it a rebate on costs, but when the farm size is exogenous the two instruments are equivalent. We also find that optimal surveillance effort, farm size, and fines are smaller for free-range farms when costs are sensitive to the degree of free-ranging.