Payments for ecosystem services (PES) are increasingly being implemented worldwide as conservation instruments that provide conditional economic incentives to landowners for a prespecified duration. However, in the psychological and economic literature, critics have raised concerns that PES can undermine the recipient's intrinsic motivation to engage in pro-environmental behavior. Such "crowding out" may reduce the effectiveness of PES and may even worsen conservation outcomes once programs are terminated. In this study, we harnessed a randomized controlled trial that provided PES to land users in Western Uganda and evaluated whether these incentives had a persistent effect on pro-environmental behavior and its underlying behavioral drivers 6 y after the last payments were made. We elicited pro-environmental behavior with an incentivized, experimental measure that consisted of a choice for respondents between more and less environmentally friendly tree seedlings. In addition to this main outcome, survey-based measures for underlying behavioral drivers captured self-efficacy beliefs, intrinsic motivation, and perceived forest benefits. Overall, we found no indications that PES led to the crowding out of pro-environmental behavior. That is, respondents from the treatment villages were as likely as respondents from the control villages to choose environmentally friendly tree seedlings. We also found no systematic differences between these two groups in their underlying behavioral drivers, and nor did we find evidence for crowding effects when focusing on self-reported tree planting behavior as an alternative outcome measure.
Keywords: behavioral impact; climate change; intrinsic motivation; motivation crowding; payments for environmental services.