Population estimates of the Endangered Hawaiʻi ʻĀkepa (Loxops coccineus) in different habitats on windward Mauna Loa

The global population of the endangered Hawaiʻi ʻĀkepa (Loxops coccineus) is estimated at approximately 16,428 birds, with stability or growth observed in the two largest populations on Mauna Kea. This study used point-transect distance sampling to estimate abundance across five distinct populations, including those in Hawaiʻi Volcanoes National Park and Kaʻū Forest Reserve on windward Mauna Loa. Population densities varied significantly by habitat, reaching 1.03 birds per hectare in open-canopy montane ʻōhiʻa woodland but were highest (1.42 birds/ha) in closed-canopy forests on Mauna Kea, where the species relies on cavities in tall trees. Surveys revealed stark differences in nesting habitat availability between Mauna Loa and Mauna Kea, suggesting potential behavioral adaptations. The global estimate aligns with a 1986 figure, indicating no drastic decline over three decades.

Judge, S. W., Camp, R. J., Hart, P. J., & Kichman, S. T. (2018). Population estimates of the Endangered Hawaiʻi ʻĀkepa (Loxops coccineus) in different habitats on windward Mauna Loa. Journal of Field Ornithology, 89(1), 11–21. Portico. https://doi.org/10.1111/jofo.12243