e161 RESEARCH REPORT Sign language endangerment and linguistic diversity Ben Braithwaite University of the West Indies at St. Augustine It has become increasingly clear that current threats to global linguistic diversity are not re- stricted to the loss of spoken languages. Signed languages are vulnerable to familiar patterns of language shift and the global spread of a few influential languages. But the ecologies of signed languages are also affected by genetics, social attitudes toward deafness, educational and public health policies, and a widespread modality chauvinism that views spoken languages as inherently superior or more desirable. This research report reviews what is known about sign language vi- tality and endangerment globally, and considers the responses from communities, governments, and linguists. It is striking how little attention has been paid to sign language vitality, endangerment, and re- vitalization, even as research on signed languages has occupied an increasingly prominent posi- tion in linguistic theory. It is time for linguists from a broader range of backgrounds to consider the causes, consequences, and appropriate responses to current threats to sign language diversity. In doing so, we must articulate more clearly the value of this diversity to the field of linguistics and the responsibilities the field has toward preserving it.* Keywords: language endangerment, language vitality, language documentation, signed languages 1. Introduction. Concerns about sign language endangerment are not new. Almost immediately after the invention of film, the US National Association of the Deaf began producing films to capture American Sign Language (ASL), motivated by a fear within the deaf community that their language was endangered (Schuchman 2004). More re- cently, as language endangerment and language documentation have grown in signifi- cance within the field of linguistics, sign language linguists have also begun to consider how language endangerment may be affecting signed languages. Johnston’s (2004) paper on the uncertain future of Australian Sign Language (Auslan) and Nonaka’s (2004) discussion of sign language endangerment in Thailand were particularly impor- tant early contributions, and the literature has been growing rapidly since then. Major sign language documentation projects are now underway around the world (see, for ex- ample, Schembri 2010). In 2011 the World Federation of the Deaf (WFD) and European Union of the Deaf (EUD) organized the conference Sign Languages as Endangered Languages, and a project at Lancaster University’s International Institute for Sign Lan- guages and Deaf Studies (iSLanDS) conducted a survey on sign language vitality, which found that none of the languages surveyed was safe (Safar & Webster 2014). Coming out of this work, UNESCO’s Atlas of the World’s Languages in Danger now includes sign languages, and a Consultative Expert Meeting on Sign Language Endan- germent was held at UNESCO in February 2017. Meanwhile, Ethnologue has recently developed an adapted method for assessing the vitality of sign languages (Bickford, Lewis, & Simons 2015), and the number of sign languages listed in that work has been steadily growing. Printed with the permission of Ben Braithwaite. © 2019. * This article grew out of work with signing communities around the Caribbean, where the tremendous di- versity of signed languages is largely undocumented and facing immediate critical threats from multiple sides. I am indebted to signers around the region, and especially to Ian Dhanoolal and Bryan Rodrigues for their invaluable collaboration. I am grateful to Diane Lillo-Martin and an anonymous referee for valuable feedback, and I owe special thanks to Andries Coetzee for encouraging me to develop this paper beyond the scope that I had originally imagined for it.