Integrating historical sources for long-term ecological knowledge and biodiversity conservation

Historical data sources are instrumental in biodiversity research because they provide historical baselines for species and ecosystems, and they reveal information about human–nature relationships and their sustainability (or lack thereof) over long timescales. Yet historical sources remain under-used in biodiversity and conservation research, in part owing to the perceived difficulty in finding, extracting and interpreting the data they contain. Their use also often relies on collaborations where overcoming disciplinary silos requires time-intensive processes of mutual acculturation. In this Perspective, we identify connections between historical ecology, biodiversity research and conservation by reviewing the main types of historical sources that contain biodiversity-relevant information and discussing how they can be extracted and integrated to draw inference about species, ecosystems and socio-ecological systems. Emerging tools and technologies are improving data mobilization efforts, but further action is needed to make best use of these types of data. We propose a strategy to improve the availability and use of historical data for biodiversity research and conservation. Historical ecology uses a wide and varied range of sources to investigate long-term dynamics of ecosystems, species and their traits, and different dimensions of nature–human interactions. This Perspective discusses the value of this approach for biodiversity and conservation science, and offers a strategy for the continued development of the field.