Native Forest Restoration

The available habitat for the critically endangered Kiwikiu and several other native forest birds on Maui is largely restricted to native forest above 4,500 ft. due to invasive plant species, mosquitoes, and avian disease. Although Kiwikiu is now only found on the windward (northeast) slopes of Haleakalā, fossil evidence suggests the species existed throughout the island and may have even preferred koa-dominated forests including those found on the leeward (southeast) slopes of Haleakalā. The leeward native forests today are significantly reduced, and the habitat has been denuded through over-grazing and introduction of non-native species. It is thought that the combination of non-native ungulate grazing and the expansion of non-native grasses prevent natural regeneration of this forest. The resulting current conditions are of aging trees within a savanna-like habitat structure with little new growth or understory. As a result, there is significant interest in restoring this forest to serve as a functional watershed as well as provide habitat for threatened flora and fauna.

The Nakula Natural Area Reserve (NAR) was created in 2011 by the State of Hawai'i-Department of Land and Natural Resources- Natural Area Reserve System (NARS). This 614-ha area is within the Kahikinui division of the mountain, and fenced areas have been and are still being completed to fence out all ungulates.

In 2012, an approximate 170-ha section of the Nakula NAR was fenced and all ungulates were removed. Shortly thereafter, MFBRP, in collaboration with the State of Hawai'i-Division of Forestry and Wildife (DOFAW), NARS, and the American Bird Conservancy, began experimental restoration trials within the fenced area to identify the most efficient and effective method(s) of restoring the forest in Nakula NAR. Once the “best” techniques have been determined, partners will be able to move forward in re-foresting the greater Nakula area. As of January 2016, these trial plots have been monitored for two years. Expect a report in 2017 about the results soon. For more details on the protocols we used to set up these experimental plots, see Protocols for Restoration Trails in Nakula Natural Area Reserve. For a summary of what has already occurred in Nakula, see Nakula Update, Trip Reports, and Newsletters.

In the meantime, MFBRP has continued to work on restoring the native forest in the 170-ha section of Nakula NAR. Work in Nakula typically consists of seed collection, planting native seedlings, monitoring plants for growth and survival, and managing invasive species. Volunteers are typically needed for these remote field trips.

Eventually much of the leeward area will need to be restored to make up for the loss of habitat that may occur due to climate change (warm weather allowing mosquitoes and avian malaria to persist at higher elevations). Leeward Haleakalā Watershed Restoration Partnership, the State of Hawai'i, Haleakalā National Park, and many others (see Partners) are all working together to restore this land for our watershed and our native species. Kiwikiu and other native bird species will also eventually be reintroduced to this side of the mountain (see Kiwikiu Recovery).

A presentation about this project: Mounce HL, Warren CC, Farmer C, Vetter JP, Berthold LK, Landon P, Fretz S. 2015. Planning for Kiwikiu reintroduction: Habitat restoration in Nakula Natural Area Reserve, Maui. Presentation. Hawai'i Conservation Conference, Hilo, HI. View presentation here.

Below is a map of Nakula Natural Area Reserve on Maui. It shows where MFBRP has been planting and restoring forest. The site is between ~5000 and ~6000 ft in elevation. For more information on Nakula, see Field Sites.

Overview of where Nakula Restoration Trials are on Maui within Nakula Natural Area Reserve.