This paper proposes a discourse-based approach to the language documentation of local ecological knowledge (LEK). The knowledge, skills, beliefs, cultural worldviews, and ideologies that shape the way a community interacts with its environment can be examined through the discourse in which LEK emerges. 'Discourse-based' refers to two components: (1) the discovery and collection of LEK and its contexts through methods informed by the ethnography of communication, and (2) the analysis of speech that encodes LEK in the framework of Interactional Sociolinguistics. This discourse-based approach not only addresses the general need to accumulate more instances of speech (about LEK, or otherwise) in a documentary corpus, but also provides an analysis of the communicative event, one that sheds light on the dynamic nature of the content of that speech in the particular sociocultural context of that speech community, embedded in discursive moments. Fundamental to this approach is the need for collaboration across disciplines. This paper explores the links that can be made among the fields of language documentation, ethnobiology, and sociolinguistics.