Short Presentation Australian Marine Sciences Association 2026 Conference

Evaluating the Impact of Conservation Policies on Coastal Ecosystems (139334)

Christopher Brown 1 , Lydia Slobodian 2 , Aldrie Amir 3 , Maria Fernanda Adame Vivanco 4 , Sy Baker 2 , Justine Bell-James 5 , Christina Buelow 6 , Jacob Bukoski 7 , Rachael Carrie 8 , Alejandra Calzada Vazquez Vela 9 , Kai Ching Cheong 4 , Rod Connolly 4 , Nadine Heck 10 , David Lagomasino 10 , Frida Sidik 11 , Mischa Turschwell 4 , Jaramar Villarreal-Rosas 4 , Alexandra White 4 , Dominic Andradi-Brown 12
  1. IMAS, UTas, Taroona, TASMANIA, Australia
  2. Georgetown University Law Center, Georgetown
  3. Universiti Kebangsaan Malaysia, Bangi
  4. School of Environment and Science, Griffith University, Gold Coast
  5. University of Queensland, Brisbane
  6. The University of Sydney, Sydney
  7. Oregon State University, Corvallis
  8. University of Leeds, Leeds
  9. World Wildlife Fund, Mexico City
  10. East Carolina University, NC
  11. Research Center for Oceanography, National Research & Innovation Agency, Jakarta
  12. World Wildlife Fund, Washington D.C.

Conservation of the world’s ecosystems can occur through multiple legal pathways, from protected areas that focus on biodiversity conservation to national scale policies and laws that coordinate, manage, and regulate uses of ecosystems. Protected areas have mixed benefits for biodiversity outcomes; what is less clear is how best to evaluate the benefits of national policies and laws for ecological outcomes. We will provide a brief introduction to impact evaluation for marine scientists, and show an example of using causal analysis to ask if national policies have prevented mangrove deforestation. We used global databases of conservation policies and mangrove deforestation to attribute change in deforestation to policies. We found that policies that restricted cutting and clearing reduced mangrove losses by up to 59% compared to a baseline of no cutting policies, but the effectiveness of these policies has diminished more recently. Our results show that conservation can occur beyond protected areas and that national scale policies and laws are an important pathway for mangrove conservation. More generally, impact evaluation methods are rarely used in marine science, where policy assessments have largely relied on correlative analyses. Adopting causal, counterfactual approaches offers major opportunities to strengthen evidence on what works to protect marine ecosystems and to better inform policy and investment decisions.