The Biodiversity Heritage Library (BHL) is the world’s largest open access digital library for biodiversity literature and archives. BHL is transforming global research by providing free, worldwide access to knowledge about life on Earth.
To document Earth’s species and understand the complexities of rapidly changing ecosystems in the midst of a major extinction crisis and accelerating climate change, researchers require access to the world’s collective knowledge about biodiversity — something that no single library can provide. While natural history books and archives contain information that is critical to studying biodiversity, much of this material has historically been accessible only in a handful of institutions worldwide. This lack of access has long been recognised as a significant barrier to efficient scientific research.
Administratively hosted by the Council on Library and Information Resources (CLIR), BHL operates as an international consortium of natural history, botanical, research, and national libraries. Together, these partners collaborate to digitize biodiversity literature held in their collections and make it freely available through a shared open-access platform that supports the world’s biodiversity research community.
The BHL portal provides free access to hundreds of thousands of volumes, comprising more than 63 million pages dating from the 15th to the 21st centuries. The historical literature and original materials in BHL’s collection may contain content that is outdated or harmful. As part of its ongoing responsibility as a digital library committed to equity and inclusion, BHL provides an Acknowledgment of Harmful Content across its websites.
In addition to public domain content, BHL works with rights holders to obtain permission to make in-copyright materials openly available under Creative Commons licences. Through Flickr, BHL also provides access to more than 300,000 freely reusable nature images from its collection, expanding discovery and engagement across research, education, art, and design. BHL further supports a variety of volunteer projects that enable the public to help enhance and enrich collection data.
The BHL consortium works closely with the international taxonomic community, publishers, bioinformaticians, and information technology professionals to develop tools and services that facilitate discovery, interoperability, and reuse of content and data. BHL aggregates data contributed by its consortium partners and Internet Archive contributors. BHL provides a range of services, data exports, and APIs to allow users to download content, harvest source data files, and reuse materials for research purposes. Through taxonomic intelligence tools developed by Global Names Architecture, BHL indexes scientific names throughout the collection, enabling researchers to locate literature relating to specific taxa.
Since its launch in 2006, BHL has served more than 16 million people in over 240 countries and territories worldwide. Through ongoing collaboration, technical innovation, and an enduring commitment to open access, the Biodiversity Heritage Library continues to advance global research and ensure that everyone, everywhere has access to the knowledge needed to study, explore, and conserve life on Earth.
Learn more about the history of BHL.