This species is endemic to Kauai and the Waianae Mountains of Oahu. Although it is a very distinctive and conspicuous tree, it was not discovered until the 1960's when it was found on Kauai. It was not discovered on Oahu until the mid 1980's. The species appears to number under 1,000 individuals, with the majority of the plants on Kauai. The species faces a host of threats, including goats, pigs, deer, rats, fire and alien plants.
Threats to E. haeleeleana include habitat degradation by black-tailed deer, goats and pigs, predation by rats, fire, and competition from non-native, invasive plants (USFWS 1999).
Number of Populations: 15 (USFWS 2001)
Number of Plants: 450-625 (USFWS 2001)
The National Tropical Botanical Garden (NTBG), Department of Land and Natural Resources (DLNR), and the Waimea Arboretum has successfully propagated E. haeleeleana.
A report entitled U.S. Army Garrison Hawaii, Oahu Training Areas, Natural Resource Management Final Report has been completed by the Army Environmental Staff. This report entails detailed management plans and descriptions of completed actions for each endangered species that occurs on Army land. The Army Environmental staff has also conducted intensive rat control around the Keawaula population in order to collect seed and be able to propagate seed in their seedhouse (USFWS 1998).
Fences were constructed by the State Division of Forestry and Wildlife (DOFAW) enclosing about half the individuals of E. haeleeleana in Mahanaloa Valley on Kauai (USFWS 1999).
DLNR-DOFAW Kauai has out-planted 13 plants grown at NTBG from 3 source collections.
NTBG currently has ex situ holdings of seeds in their seed bank, which represents four out of the fifteen populations. In addition, there are 29 plants that represent two populations growing in the botanical garden.
In May 2002, the U.S. Fish and Wildlife Service determined that a designation of critical habitat was prudent for this species. (USFWS 2002)
1. Construct enclosures to protect populations against feral ungulates. Testing the effects of fencing would be the first priority before constructing the enclosures.
2. Control competing alien species such as Lantana camara (lantana), Psidium cattleianum (strawberry guava), Grevillea robusta (silk oak), Melinus minutiflora (molasses grass), Passiflora mollisima (banana poka) and Rubus rosifolius (thimbleberry). Weed control is also necessary within existing exclosures such as Mahanaloa Valley.
3. Maintain adequate genetic stock. Ex situ propagation should be continued to prevent extinction. Propagation materials should be collected immediately from populations with few individuals, such as Haeleele Valley, Kawaiula Valley, Koaie Canyon, and Pohakuao on Kauai, and Kahanahaiki Valley, and Kaumokuiki Ridge on Oahu.
4. Enhance wild populations and establish new populations. After propagated material is available, and after fencing and weeding are underway, outplanting should be done to enhance wild population. New populations should be established within the historic range of Euphorbia haeleeleana.
5. Reduce threats from rats. A management plan should be developed and implemented to control the rat population.
6. Protect plants from fire. A fire plan should be developed and implemented, especially by the Army on the Makua Military Reservation where current ordinance training exercises could unintentionally ignite fires.
7. Map genetic diversity in the surviving populations of E. haeleeleana.
8. Conduct pollination studies on E. haeleeleana.
Recommendations derived from M.H. Chapin, M. Maunder, and USFWS (1999).
1. Establish secure ex situ stocks with full founder representation.
2. Survey ex situ holdings and conduct molecular fingerprinting.
3. Develop proper horticultural protocols and pest management for E. haeleeleana.
Recommendations derived from M.H. Chapin and M. Maunder.
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