Natural resources, by their nature, are not readily bent to the status of private property. Efficient resource use is complicated by jurisdictional externalities, public goods, non-use values, and beneficiaries spatially separated from the location of resources. The task is made more challenging by ecological complexity that obscures cause (benefits) and effects (costs), and dramatic time lags between individual actions and subsequent social consequences that, together with substantial uncertainty, introduce the chance of irreversibilities. Resource economists have played a major role in the literature on externalities, the development of individual transferable quotas, non-market valuation techniques and common property management.

We examine the structure of preferences for mitigating impacts of global climate change that will not occur during the lifetimes of most who are alive today. Because no market data exist for such distant markets, a statedpreference approach is used. The analysis is based on the random-parameters logit model, and the results indicate substantial heterogeneity in respondent preferences, that mean willingness to pay is a significant and increasing function of the scope of the impact, and, provocatively, that respondents have the same preferences over the two very different time horizons that we consider.

M ANY individuals derive satisfaction through hunting waterfowl. The utility of the birds as a consumption good implies that some scarce resources, primarily ponds and breeding birds, should be devoted to game production. The migratory nature of the wildfowl precludes a conventional system of property rights and prevents market determination of optimal resource quantities to be devoted to production. In general, the production of waterfowl requires the use of Canadian natural resources but more than two-thirds of the birds are consumed by United States hunters, thereby creating an externality of international scope. Precise hunting regulations are established by each state under the general supervision of the federal government. Since no evidence indicates trade in this commodity among the states, an additional jurisdictional externality is created. In the model to be developed, we identify the transient and steady-state management conditions necessary to achieve a social optimum. Subsequent applied analysis pertains only to the steady-state situation. We can anticipate conclusions from the applied analysis, to be developed in due course. Because farmers obtain revenue from agricultural crops grown on drained wetlands but do not receive revenue from the crop of waterfowl raised on ponds left in their natural state, North American wetlands are being drained more rapidly than the economically optimum rate. Indeed, we believe the optimum situation requires creating, not draining, wetlands. Expansion of the absolute number of breeders is also required, although optimal input proportions are obtained through a lesser relative increase in this factor.

SHORELINE development is a growing public policy issue in many urban areas. While there is some published research on a related topic, the importance of ambient water quality, economists have not yet turned their attention to the economic significance of the existence and width of the undeveloped apron offering public use and access to bodies of water in urban areas. There are several important issues to be considered here. May we expect the urban land market to provide a solution which is Pareto efficient? Have public agencies through zoning and other building restrictions acted in a socially optimal way? What contribution can studies of the determinants of property values make to our understanding of these issues? We begin an exploration of these issues and present some empirical results that enhance our knowledge of the economics of water-related open space. More generally. this paper extends recent economic work that has produced quantitative measures of value for phenomena hitherto restricted to qualitative expression. The process of transforming qualitative into quantitative knowledge, so essential to an empirical science as to be one of its distinguishing features, is well illustrated by the work of Cobb and Douglas on production (1928); Griliches (1961) on the qualitative characteristics of automobiles; and Fogel and Engerinan's (1974) controversial piece on slavery.' With respect to hotusing, implicit prices of each attribute contained in the bundle of housing services have been estimated by hedonic price regressions in the spirit of the work by Lancaster (1971) and others.2 In the following sections we first examine the choice of housing attributes, including waterrelated open space and proximity to bodies of water, faced by a household in a metropolitan area. Next, the process of implicit price formation is examined, and, employing data on individual dwelling units in a metropolitan area with numerous bodies of water, these implicit prices are estimated. We then turn to the question of what can and cannot be inferred from these results about the demand for open space and the welfare gains or losses resulting from possible changes in the amount of water-related open space.

We argue that the most commonly used measures of natural resource scarcity are deficient. The discussion begins with some general comments on natural resource scarcity, then turns to a description and evaluation of each of the major scarcity indices: unit cost, product output prices, and rental rates. Rental rates or a useful proxy, marginal discovery costs, are preferred over the rival measures. But there are important instances where good scarcity indicators may be entirely absent.

We argue that the most commonly used measures of natural resource scarcity are deficient. The discussion begins with some general comments on natural resource scarcity, then turns to a description and evaluation of each of the major scarcity indices: unit cost, product output prices, and rental rates. Rental rates or a useful proxy, marginal discovery costs, are preferred over the rival measures. But there are important instances where good scarcity indicators may be entirely absent.

The hedonic travel cost method is a technique which reveals how much users are willing to pay for the individual characteristics of outdoor recreation sites. The prices of recreation attributes are estimated by regressing travel costs on the bundles of characteristics associated with each of several potential destination sites. The demand for site characteristics on site quality is then revealed by comparing the site selection of users facing different attribute prices. The technique is applied to value steelhead fish density in Washington State streams.