The conservation of biodiversity and ecosystems is increasingly recognised as essential to the long-term sustainability of organisational operations. Drawing on critical mass theory, upper echelon theory and gender socialisation theory, this study examines the influence of female board and executive representation on corporate biodiversity disclosure, with particular attention to critical mass thresholds. Additionally, we investigate the moderating role of internal environmental teams in strengthening the relationship between gender diversity and biodiversity disclosure. Using a panel dataset comprising 22,029 firm-year observations from 2535 firms across 42 countries, our findings underscore robust empirical evidence that a critical mass of female directors and executives is positively associated with enhanced biodiversity disclosure. Furthermore, we find that the presence of an environmental team significantly affects this relationship, particularly when female representation on the board is below the critical mass threshold. These findings have important implications for policymakers, corporate boards and sustainability leaders, emphasising the organisational mechanisms needed to integrate biodiversity governance into strategic decision-making.