Are there income effects on global willingness to pay for biodiversity conservation?

This paper is concerned with the empirical relationship between biodiversity conservation valuesand income. We use random effects panel models to examine the effects of income, and then GDPper capita, on willingness to pay for habitat and biodiversity conservation. In a meta-analysis, 145Willingness To Pay estimates for biodiversity conservation where existence value plays a majorrole were collected from 46 contingent valuation studies across six continents. Other effectsincluded in the meta-analysis were the study year; habitat type; continent; scope as presented torespondents; whether WTP bids were for preventing a deterioration or gaining an improvement inconservation, whether a specific species or specific habitat was protected; whether the questionnaireused a dichotomous choice or an open-ended format; distribution format; and the choice of paymentvehicle. GDP per capita seemed to perform as well as an explanatory variable as respondent’s meanstated income, indicating that it is wealth in society as a whole which determines variations in WTP.Our main conclusion is that the demand for biodiversity conservation rises with a nation’s wealth,but the income elasticity of demand is less than one.