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Maui Invasive Species Committee.

Miconia is an especially aggressive invader because of its fast growth, dense canopy, prolific reproduction, and ease of dispersal. In Hawaii's climate, miconia quickly towers over surrounding plants, its giant leaves creating such deep shade that few native seedlings and shrubs can persist. One tree can produce 15,000 to 12 million seeds several times each year. Birds, especially the many species of alien birds in Hawaii's lowlands, eat the juicy miconia fruits and carry the seeds into new areas. Likewise, hikers and feral pigs unwittingly track the minute seeds into forests not yet invaded by miconia. Search by helicopter is an effective way to locate mature miconia in remote rainforests.

Alien treefrogs are another of Hawaii's new invasive threats. First reported in 1997, the Puerto Rican "coqui" (Eleutherodactylus coqui) may pose an especially severe threat to native insects (and indirectly to birds)in Hawaiian rainforests. In its native habitat, coqui densities exceed 20,000 animals per hectare, consuming an average of 114,000 food items per night per hectare! Three Caribbean tree-frog species are appearing in Hawaiian greenhouses and nurseries on imported plants. The frogs are spreading from nurseries and are being transported by residential and resort landscaping on plants from those nurseries. The tree-frogs' painfully piercing calls even pose a potential nuisance to human residents and resort guests. The MISC is investigating the feasibility of tree-frog control in Hawaii.

Biological invasions are causing severe problems worldwide, but oceanic island ecosystems are exceptionally vulnerable to invading weeds and animals. In his forward to Robert Devine's new book, Alien Invasion, Secretary of the Interior Bruce Babbitt contends that we have the means to cope with the invasion of alien (non-native) species if we act quickly and in concert with others. Devine's discussion on "Choosing Our Future, Saving Our Past" showcases networking efforts against alien species on the Hawaiian island of Maui. Indeed, grassroots efforts on Maui are resulting in effective cooperation among a wide variety of interests in dealing with alien threats. Whether this approach will succeed in stemming the tide of alien species remains to be seen, but participants in a local partnership called the Maui Invasive Species Committee are excited over the prospects.

The idea of working together to address alien invasions on Maui was stimulated by the threat to conservation lands from Miconia calvescens, Tibouchina herbacea (glorybush), and Clidemia hirta (Koster's curse)--three aggressively invasive plants in the family Melastomataceae. The Melastome Action Committee (MAC) was formed in August 1991 through the initiative of Randy Bartlett, Pu`u Kukui Watershed Supervisor for the Maui Pineapple Company, and Ernest Robello, Project Director of the Tri-Isle (Maui County) Resource Conservation and Development Office of the U.S. Department of Agriculture. The following State, private, and Federal entities have met regularly as MAC members since 1991: Hawaii Department of Land and Natural Resources (DLNR), Hawaii Department of Agriculture (HDOA), Maui Economic Development Board, The Nature Conservancy of Hawaii, the National Park Service, the U.S. Forest Service, the Biological Resources Division of the U.S. Geological Survey (USGS/BRD), and the Pacific Cooperative Studies Unit of the University of Hawaii (PCSU/UH, now with USGS/BRD). More recently, the U.S. Fish and Wildlife Service joined MAC. The group's activities include public education, providing information to the Hawaiian State legislature and Maui County government, and planning chemical, mechanical and biological control programs.

Miconia: The "Green Cancer" of Tahiti

The invasive tree miconia (Miconia calvescens) has been MAC's primary target to date. This species, native to neotropical forests at 1,000-6,000 feet (300-2,000 meters) in elevation, has proven to be an unusually aggressive invader of moist tropical island habitats. Introduced to Tahiti from South America in 1937, dense thickets of miconia had entirely replaced the native forest over most of the island by the 1980's, with a dramatic reduction in biological diversity. After the late ecologist F.R. Fosberg saw miconia in Tahiti in 1971, he reported that "it is the one plant that could really destroy the native Hawaiian forest." Yet because of its attractive purple and green foliage, it had already been brought to Hawaii as an ornamental in the 1960's, and no sustained efforts were made to control it until it became well established on the island of Hawai`i.

After conservation agencies discovered miconia on Maui in 1990, they raised an alarm. This species appeared to pose an especially severe threat to the high-elevation rainforest habitat of many endemic and endangered forest birds and plants. Thanks to a public education campaign, miconia has become something of a household word on Maui and progress is being made against it. A full-time 5-man crew funded by Maui County and supervised by the DLNR is combating this weed's primary infestation site near Hana, and over 850 acres (345 hectares) have been treated. The Nature Conservancy is taking the lead in dealing with outlying populations. With assistance from scientists in Brazil, USGS/BRD and PCSU/UH biologists have found fungi in miconia's home range that may prove to be useful biocontrol agents, and the HDOA is conducting tests. So far, one fungus has been released for biocontrol and it is now established on the islands of Maui and Hawai`i.

Work against miconia is progressing well, though the battle is far from won. However, other invasive species continue to appear with alarming frequency. In December of 1997, members of MAC decided to form another group to address a broader range of invasive pest species problems in Maui County. This group, the Maui Invasive Species Committee (MISC), is a voluntary partnership of private, government, and nonprofit organizations committed to preventing new pest species--plant and animal--from becoming established in Maul County and to stop newly established pests from spreading wherever possible. The MISC recognizes that, rather than focusing exclusively on threats to biodiversity, it must address a wider range of threats (to agriculture, health, quality of life) to elicit a broader base of support. It seeks to establish relations with, and encourages the participation of, the Maui Association of Landscape Professionals, Maul Chamber of Commerce, Maul Economic Development Board, Maul Farm Bureau, Maul Hotel Association, Maui Visitors Bureau, and similar groups.

The greatest challenge is to obtain funding and personnel to carry out alien species control work in an era of shrinking governments. Is success possible? The MISC developed a plan for priority species to combat, resources needed, and possible funding sources at a workshop in September 1998. All participants agreed that education is a crucial ingredient of the anti-alien species strategy and that direct public involvement in selected eradication efforts is an important tool. The group's future successes and failures may guide efforts statewide and even influence the approaches taken elsewhere in the world to combat the threats to native ecosystems posed by alien invasions.

Lloyd Loope is Research Scientist with U.S. Geological Survey, Biological Resources Division, Pacific Island Ecosystems Research Center, at Makawao, Maui, Hawaii. Randy Bartlett is Pu'u Kukui Watershed Supervisor, Maui Pineapple Company, Lahaina, Maui, and Chair of the Maui Invasive Species Committee.
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Author:Loope, Lloyd; Bartlett, Randy
Publication:Endangered Species Bulletin
Geographic Code:1U9HI
Date:Nov 1, 1998
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