Measuring the effectiveness of using rangers to deliver a behavior change campaign on sustainable palm oil in a UK zoo.

A fundamental objective of modern zoos is promoting pro-environmental behaviors. This study experimentally assessed the contribution of zoo rangers (staff employed to engage visitors) in delivering a behavior change campaign promoting sustainable palm oil use. The campaign was delivered in a dedicated area in a walk-through animal exhibit, with rangers either "present" or "absent" in the campaign space. Questionnaires assessing awareness, knowledge, and purchasing intentions were completed by 1032 visitors. Two analyses were conducted: (1) comparing the impact of ranger presence versus absence (to assess the overall impact of having rangers present regardless of whether they talked to visitors) and (2) comparing the impact of talking to a ranger against demographically matched individuals visiting when rangers were absent (to assess the specific impact of talking to a ranger). Visitors who talked to rangers were more aware of palm oil, had more knowledge, and greater intentions of purchasing sustainable palm oil. However, as only one-quarter of visitors talked to a ranger, fewer differences were found comparing ranger presence versus absence. These findings suggest that rangers can be instrumental in communicating complex conservation issues and delivering zoo-based behavior change campaigns, but their impact is limited by low engagement rates.