Comparing Local Residents’ Willingness to Pay (WTP) and Willingness to Volunteer (WTV) for Water Onion (Crinum thaianum) Habitat Conservation

In subsistence economies where cash is scarce, non-monetary numeraires can be used instead of cash as utility measures. In this study, we investigate the values of the Thai water onion (Crinum thaianum) (WO), an endangered native wetland plant, for each service enhancement in Thailand, by using willingness to pay (WTP) money and willingness to volunteer (WTV) to measure the value of WO habitat conservation outcomes, including biodiversity, water quality, upstream conditions, and recreational opportunities. This study employs choice experiment (CE) surveys and face-to-face interviews with villagers in the WO areas of Phangnga and Ranong provinces in southern Thailand. The results show that improved upstream conditions are the most important benefit for residents, followed by biodiversity and water quality. Improving upstream conditions, biodiversity, and water quality from low to high would increase estimated annual welfare by USD 89 per person, while local residents would also provide an annual WTV of 80.2 days per person in exchange for considerable improvements in upstream conditions, biodiversity, and water quality. We found that low-income people are more likely to provide labor to improve ecosystem services. Overall, the findings suggest that the labor value, just as the monetary value, can also be used to evaluate the preferences for increased ecosystem services. This study implies that employing volunteer labor as a means of payment for accurate welfare estimations might be a practical alternative, and also allowing respondents to indicate their WTV may lead to an increase in the estimated value of ecosystem services.