As part of a larger study looking at the seasonal distribution and relative abundance of the southern house mosquito Culex quinquefasciatus in Kīpahulu Valley, Haleakalā National Park, C. quinquefasciatus egg rafts were collected to develop field techniques and determine differences in egg viability (percent hatch) in wild populations. Ovicups baited with a 5-day-old timothy hay infusion were co-located with Sentinel traps and operated for one week, twice during each sampling season at Kipahulu study sites Delta Camp (915 m asl) and Palikea Camp (1280 m asl) from 9 March 2023 to 20 September 2023. Egg rafts were also collected at Hawai'i Volcanoes National Park opportunistically to further develop field techniques and determine wild mosquito egg viability.