Glottalisation as a cue to coda consonant voicing in Australian English

Recent research has suggested that some long vowels exhibit a constraint on voiceless coda induced shortening in Australian English. This constraint has the potential to compromise the vowel length cue to coda voicing, raising questions about how the coda stop voicing contrast is preserved if vowel duration cues are weakened. One possibility is that glottalisation and vowel duration are exploited in a trading relationship as cues to coda voicelessness. We conducted an apparent time study using a highly constrained dataset to determine whether vowel duration and the presence of glottalisation covary as cues to coda stop voicing and whether there is evidence of recent change to the weighting of these cues in Australian English. The incidence of glottalisation and temporal aspects of voiced and voiceless rhymes were analysed in the speech of male and female speakers from two different age groups. Results showed that younger speakers exhibited greater use of glottalisation in voiceless contexts in association with reduced coda voicing-related vowel duration cues compared to older speakers. These finding raise questions about the weighting of glottalisation and vowel duration as cues to coda stop voicing and may suggest change in progress regarding the management of voicing cues in the rhyme.