Using choice modelling to estimate the non-market benefits of coral reef restoration in the Philippines

Abstract

Coral reef health decline in the Philippines provides an impetus for reef restoration investments. A benefit-cost analysis can be used to support policy-relevant decisions on such investments. However, to our knowledge, most benefit-cost analyses conducted for coral reef investments in the Philippines have been inadequate because they have used non-marginal values, proxies and benefit transfers as benefit estimates, or have been cost-effectiveness studies. To overcome this information inadequacy, this paper reports estimates of coral reef restoration non-market values in the context of an investment in Mass Larval Enhancement on two scales in the Philippines - restoration on a single coral reef and restoration on a nation-wide scale. Using choice modeling for two split samples (locals living near the single coral reef and those living in Metro Manila), willingness to pay values for coral reef attributes that have been improved through restoration were estimated. At the single reef scale, respondents from the Manila sample were, on average, willing to pay Php 1.41 per percentage increase in coral cover, Php 0.93 per additional individual fish, and Php 1.17 per marginal increase in fish species per household monthly for ten years (Php 1.40, Php 0.62, and Php 1.15 for the same respective attributes within the local sample). At the nation-wide scale, the equivalent value estimates for the Manila sample were Php 8.70 and Php 8.13 for coral cover and fish species respectively (Php 33.06 and Php 27.05 for the local sample). Respondents overall were not willing to pay for increases in fish individuals on a national scale. Differences in the attribute value estimates between the two restoration scales provide evidence of the validity of the results. The differences in value estimates between the local and Metro Manila samples varied depending on the coral reef attribute. These results should be taken into consideration when using benefit transfer to inform benefit-cost analyses across differing populations.