The present study determined the willingness to pay for the conservation of the biodiversity (WTP) of the Yanachaga-Chemillén National Park (YChNP), applying the contingent valuation method, in hypothetical scenarios of conserving 6, 9 or 12 species that guaranteed protection of 50 % of the functionality of the ecosystems of this place. It was found that the WTP was determined by the functional characteristics that key species play in the resilience of the PNYCh ecosystems. For this reason, similar studies should evaluate the option of preferring the use of functionality instead of indicators based, for example, on the number of species.

According to NOAA, the results of an economic valuation are applicable as public policy if they fulfill two conditions: rationality and plausibility. In this study, we carried out the valuation of biodiversity conservation in Manu National Park in Peru (a megabiodiverse country), based on three representations: species, habitat and functionality. We identify sensitivity to scope in most of the attributes used. When we add socioeconomic characteristics, we identify that gender and salary levels affect preferences. Our total analysis shows that number of threatened plant species and functionality better fulfill both conditions.