The recovery of threatened and endangered species is often strongly linked to offspring survival, and positively correlated with maternal investment. Here, maternal investment strategies associated with the Main Hawaiian Island (MHI) subpopulation of Hawaiian monk seals is examined. Mother-pup pairs (n=11) were observed 0600–1600h, 7 days a week over the course of three pupping seasons (2006, 2008–2009) on the islands of Hawai'i and Moloka'i. Individual suckling events were grouped by week from birth, and by time of day (early, mid, late). Duration and frequency of nursing bouts, length of maternal care (birth to weaning), pup weaning mass, habitat usage of nursing mother-pup pairs, and nursing bout initiator and terminator were analyzed. Time spent nursing varied significantly by week (p<0.001) but not by time of day (p=0.463). Frequency of nursing bouts also varied significantly by week (p=0.008) as well as by time of day (p=0.004). Both suckling duration and bout frequency increased with age of the pup, similar to results found in Northern Elephant seals, a close relative of the Hawaiian monk seal. Length of maternal care following birth of pup ranged 46–57 d, and resulted in a mean pup weaning mass of 91.51 kg. Pup was the primary initiator and terminator of nursing bouts. Beaches and intertidal zones were preferred nursing habitat by mother-pup pairs, with beaches utilized primarily 0600–1000 h and intertidal zones 1000–1400 h. The MHI monk seal subpopulation is continuing to increase annually unlike the 6 declining subpopulations in the Northwest Hawaiian Islands (NWHI). Pups also appear to be weaning in better condition than those in the NWHI. Comprehensive knowledge of the reproductive behaviors of MHI monk seals will provide vital insight into the previously unknown maternal strategies of this subpopulation, which can be used in recovery efforts. Information presented here provides a baseline analysis of undisturbed MHI monk seals.