The role of recoverability in the implementation of non-phonemic glottalization in Hawaiian

Previous research has shown that non-phonemic uses of glottalization are often prosodically determined in a variety of languages such as English, German, Polish, and Spanish. We examine the use of inserted glottalization in Hawaiian, a language that also has a phonemic glottal stop, to determine whether the distribution and realization of non-phonemic glottalization is conditioned by higher prosodic boundaries and/or prosodic prominence as found in other languages. The spontaneous speech data in this study comes from the Hawaiian-language radio program Ka Leo Hawai'i, which featured interviews with bilingual Hawaiian–English speakers in the 1970s and 1980s (Kimura, Larry (Producer). 2020. Ka Leo Hawai'i [radio program]. Kani'āina, the digital repository of Ka Haka 'Ula O Ke'elikōlani, College of Hawaiian Language, University of Hawai'i at Hilo. Available at: https://ulukau.org/kaniaina/). Results show that non-phonemic glottalization occurs most often before an unstressed, monophthongal single-vowel grammatical marker (/a e i o/), where it is also longer, as well as before unstressed vowels and between different flanking sounds. Full closures were more likely between identical vowels, but stress does not affect realization. These results are not consistent with the use of glottalization at higher prosodic boundaries or to mark prosodic prominence. Instead, the preponderance of non-phonemic glottalization before single-vowel grammatical markers may be to ensure that these critical markers are recoverable and not perceptually subsumed by the preceding vowel.