The Effectiveness of Local Conservation Ballots

Global action to slow biodiversity loss is critically needed but comes at substantial cost. In this article, we assess the effectiveness of local ballot measures for land-based conservation projects in the United States as a way to increase bird abundance, a key conservation indicator. Using a citizen science dataset of bird observations, we employ an abundance model to estimate relative abundance conditional on observer effort and exploit a sharp discontinuity in land-based conservation funding at the vote threshold to estimate plausibly causal effects. We find that an approved ballot measure has modest but significant impacts that accrue over ten years.