This thesis proposes that the mid-central vowel /ɘ/ is non-moraic in Shiwilu (Kawapanan), following Moraic Theory (Hyman 1985, Hayes 1989) using quantitative methods and naturalistic data. The main proposal of this thesis is that the ability of this vowel to be stressed, or even to surface, is due to a mora augmentation strategy consisting of the gemination of the following segment in syllables having the mid-central vowel as a nucleus. This strategy satisfies a licensing requirement that all syllables be moraic. The thesis situates Shiwilu within a broader typology of central vowels along two dimensions: stress and position in the word. Additionally, I present a brief typology of repair strategies employed by languages to increase the mora count of syllables; Shiwilu is unique in this typology in employing gemination to turn a non-moraic syllable into a monomoraic one. This thesis also addresses a long-standing issue in research on the phonetics-phonology interface: the role of naturalistic as opposed to laboratory-based data in the evaluation of the relationship between gradient phonetic patterns and phonological categories. A quantitative demonstration of the link between moraic structure and its phonetic exponents provides support for the view that phonological weight patterns are evident even in noisy data. Results from the current study enrich both typological knowledge about the phonological behavior of central vowels and the diverse mora augmentation strategies observed cross-linguistically.