The value of qualitative approaches to impact evaluation in biodiversity conservation

To evaluate impact, conservation practitioners and researchers can pursue different approaches and draw on an array of methods. Although the suitability of specific impact evaluation methodologies varies depending on context, quantitative approaches are predominantly used due to perceptions of greater rigour and broader acceptance. However, qualitative approaches to impact evaluation can generate distinct and complementary insights. In this perspective piece, we provide a conceptualisation of qualitative approaches to impact evaluation in conservation and draw on case studies to illustrate the value of qualitative approaches. These approaches can offer unique insights to understand change by illuminating different ways of seeing, testing the validity of explicit and implicit assumptions, and helping to make sense of real-world complexity. We illustrate the value and necessity of understanding why change is occurring alongside magnitude. To promote more effective and inclusive conservation research and practice, we propose that the conservation community should strive to mainstream qualitative approaches, both independently and in conjunction with quantitative approaches, as part of the development and implementation of impact evaluation in biodiversity conservation.