Why we still struggle to turn biodiversity data into policy evidence

We now have more biodiversity data than ever before, coming from citizen science platforms, natural history collections, and global infrastructures such as GBIF. Yet policy makers still struggle to use these resources as timely and trustworthy evidence. The problem is rarely a lack of data. It is the fragile and often project specific workflows required to turn heterogeneous records into repeatable indicators and assessments. Key challenges include mismatches between data and decision needs, incomplete or inconsistent taxonomic foundations, unaddressed bias and uncertainty, and the limited durability of tools and outputs beyond individual projects. In this talk I explore why biodiversity data does not automatically become policy evidence, and what we can do about it. Drawing on work from the Horizon Europe projects TETTRIs and B-Cubed, I present approaches that link policy engagement with scalable biodiversity informatics. These include fitness for use assessment, automated and reactive workflows, standardised data cubes, and transparent handling of uncertainty and provenance. I illustrate these ideas using examples from invasive alien species monitoring and the rapidly expanding use of citizen science observations, alongside recent work to quantify taxonomic capacity and to align it with policy driven demand. My aim is to show how stronger links between taxonomy, data standards, and reproducible workflows can transform biodiversity records into evidence products that are timely, auditable, and fit for decision making at national and European scales.