The CSA/NBII Biocomplexity Thesaurus Web Service allows users to query the Thesaurus for matching and relating terms using a variety of search operators. The Biocomplexity Thesaurus is a merger of the CERES/NBII Thesaurus and the CSA Aquatic Sciences and Fisheries, Life Sciences, Pollution, Sociological, and Ecotourism thesauri.
In 2004, the CSA Ecotourism Thesaurus was also merged into the Biocomplexity Thesaurus. Merging and reconciliation of the terms in these thesauri was performed by Jessica Milstead, a leading expert in the development of scientific thesauri. In 2007, USGS assumed editorial management of the Biocomplexity Thesaurus, and now leads expansion of the thesaurus, addition or modification of terms, and development of tools and services to enable the use of the Thesaurus in both CSAS and external applications. In 2008, USGS significantly expanded the Biocomplexity Thesaurus to include terminology that supports the fire ecology and management communities. More than 2,000 new concepts were added to the Thesaurus.