Double Bounded Survival Values for Preserving the Landscape of Natural Parks

Measuring the economic value of natural parks is useful for deciding upon the appropriate policy actions that would lead to long-term preservation. This paper presents results from a contingent valuation study involving the preservation of the landscape of a group of natural parks situated in Gran Canaria. The area of study represents the forest reserve of the island. A double bounded dichotomous choice approach to elicit individuals» values is implemented by means of a telephone survey to the local population. Dichotomous choice answers are modelled assuming a variety of theoretical survival distributions. The lognormal distribution shows the best empirical results when compared with the exponential, Weibull and generalised gamma distributions. A test of the effects of information about related landscapes is described, showing that individuals» valuations become significantly lower when faced with the potential enhancement of their environmental choice set. Thus, this result would imply that survey design should account for potential environmental programmes that may not be specified at the time of collecting individual data. In addition, non-use values as measured by the willingness-to-pay of non-users are not significantly different from the value expressed by regular users. Thus, our results suggest that pure recreational value is a small component of total preservation value in the context of unique and scarce natural assets.