Endemic to the Waianae Mountains of Oahu, West Maui, and Hawaii Island. The total number of individuals is thought to be fewer than 300. Almost no regeneration is occurring throughout its range. Many of the remaining trees are partially dead. Fires have killed many trees on Hawaii Island within the last decade. Alien plants and introduced ungulates also threaten the species and its habitat.
Threats to C. oppositifolia include the loss of habitat by feral ungulates and invasive introduced plants, such as Pennisetum setaceum (fountain grass), Lantana camara (lantana), and Schinus terebinthifolius (Christmas berry). Fire and the coffee twig bor
Number of populations: 10 (USFWS 2001)
Number of plants: 280-300 (USFWS 2001)
The National Tropical Botanical Garden (NTBG) has germinated and propagated C. oppositifolia. The Department of Land and Natural Resources, Department of Forestry and Wildlife (DLNR, DOFAW) has also outplanted more than 64 individuals into several exclosures on Puu Waawaa (Hawaii) (USFWS 1996).
Seeds of C. oppositifolia have been tested by the Center for Conservation Research and Training (CCRT), finding that they are orthodox and can tolerate freezing and drying. The laboratory germination time was two to three weeks (Yoshinaga 2002).
Kwon and Morden (2002) used molecular markers (RAPDs) to examine the genetic structure of the remaining populations of this taxon and compared it relative to other native Hawaiian species. They found relative variation to be lower than with other Hawaiian species, larger populations to contain the highest levels of genetic diversity and smaller populations to generally contain the least.
A proposal by Ka `Ahahui `O Pu`uwa`awa`a offers a unique opportunity to protect C. oppositifolia and its main remaining habitat at Pu`uwa`awa`a. This organization is composed of residents of Pu`uwa`awa`a and Pu`u Anahulu, ecologists, land managers, and others who care deeply about this special place. Their proposal includes restoration of native ecosystems and cultural practices, public education, hunting, ranching, and ecotourism (Environment Hawaii 2001).
NTBG currently has ex situ holdings of 804 seeds in its seed bank, which represents three out of four populations. In addition, there are three plants that represent an unknown population growing in the nursery of the botanical garden.
In 2002, the U.S. Fish and Wildlife Service determined that a designation of critical habitat was prudent for this species. (USFWS 2002)
This species occurs naturally on a privately-owned site. A cattle fence has been in place here since 1950, and the site has been actively managed since 1996. At this site, management has actively removed the invasive grass, Pennisetum setaceum, thus reducing wildfire risk in the area, and has also actively removed goats, feral hogs, stray cattle, and controlled the rodent population. Additionally, numerous native understory plants have been planted. (USFWS 2002)
1. Research a control method for the coffee twig borer.
2. The habitat of C. oppositifolia to be protected from ungulates and alien plants.
3. Ensure the populations of C. oppositifolia remain viable on each of the islands that it occurs on.
4. Conduct pollination biology, and seed dispersal studies.
5. Map genetic diversity in the surviving populations of C. oppositifolia.
6. Test the influence of weeding and fencing on populations of C. oppositifolia.
Recommendations derived from M.H. Chapin, M. Maunder, and USFWS (1996).
1. Establish secure ex situ stocks with full founder representation.
2. Develop proper horticultural protocols and pest management for C. oppositifolia.
3. Survey ex situ holdings and conduct molecular finger printing.
Recommendations derived from M.H. Chapin and M. Maunder.
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