The United Nations Strategic Plan for Biodiversity 2011-2020 is a key initiative within global efforts to halt and eventually reverse the loss of biodiversity. The very first target of this plan states that "by 2020, at the latest, people are aware of the values of biodiversity and the steps they can take to conserve and use it sustainably." Zoos and aquariums worldwide, attracting more than 700 million visits every year, could potentially make a positive contribution to this target. However, a global evaluation of the educational impacts of visits to zoos and aquariums is entirely lacking in
Campaigns by zoos, aquariums, and other civil society organizations are an important tool for promoting social changes that benefit the environment. Here, we evaluate a global biodiversity education campaign's impact through a repeated-measures survey of nearly 5000 visitors to 20 zoos and aquariums located in 14 countries. By comparing visitors’ pre- and post-visit responses combined across respondents, we found significant aggregate improvements in their biodiversity understanding and their knowledge of actions to help protect biodiversity. Respondents who reported seeing the education