With help, mint plant may soon be coming up roses

A Hawaiian mint, found only in the oheo forests of Molokai and with fewer than 10 mature plants left in the wild, will be receiving some extra help as it struggles back from the brink of extinction.

Late last month, the U.S. Fish and Wildlife Service announced an addendum to the plan to recover the endangered phyllostegia hispida. The plant with no local name will be added to the existing Moloka’i Plant Cluster Recovery Plan because its habitat, threats and recovery actions are similar or identical to those for other species in the cluster recovery plan, a U.S. Fish and Wildlife Service news release said.

The action basically groups a cluster of endangered plants that share a same geography on Molokai together for protection, said Ken Foote, spokesman for the Pacific Islands Fish and Wildlife office. The recovery plan for the plant said that the Moloka’i Plant Cluster Recovery Plan originally had 19 plants listed, mostly endemic to Molokai.

Phyllostegia hispida is found only in the wet, ohia-dominated forests of eastern Molokai, between 3,650 and 4,200 feet elevation, the news release said. The plant is a nonaromatic member of the mint family (lamiaceae) and is a loosely spreading, many-branched vine that often forms large tangled masses.

“This unique species was thought to have become extinct in the 1990s but was rediscovered in 2005,” said Loyal Mehrhoff, field supervisor for the Pacific Islands Fish and Wildlife office. “Species such as phyllostegia hispida are integral to the overall health of native ecosystems in Hawaii.”

Mehrhoff said that a number of conservation organizations are undertaking efforts to manage habitat for this species, to propagate additional plants and to re-establish populations in the wild.

Organizations such as the University of Hawaii’s Lyon Arboretum on Oahu, the National Tropical Botanical Garden on Kauai, the Olinda Rare Plant Facility on Maui and the Kalaupapa National Historical Park on Molokai are propagating plants.

Land managers from the state Department of Land and Natural Resources have fenced some plants to protect them from feral pigs, and The Nature Conservancy continues to control feral pigs and non-native plants within the Kamakou Preserve, the news release said.

Currently, there are fewer than 10 wild mature plants, three wild seedlings, and about seven to 10 reintroduced plants, the news release said.

Phyllostegia hispida has rarely been seen in the wild. From 1910 to 1979, a total of eight populations were recorded but in subsequent years died for various reasons, the news release said. With surveys not locating new plants, the species was thought to have gone extinct – until 2005 when two seedlings were discovered at the Kamakou Preserve.

Phyllostegia hispida was designated an endangered species on March 17, 2009. No known population is entirely protected from factors threatening the species, the news release said.

The plant’s most significant threat is its low numbers, because random events such as hurricanes or disease outbreaks could send the plant to extinction, the plant recovery report said. Other threats are habitat degradation by feral pigs and invasive alien plants and by landslides and flooding, rats and non-native slugs. Native caterpillars also may pose a threat to the plant.

To prevent the extinction of phyllostegia hispida and ultimately to recover the species, the service recommends protecting, managing and increasing all known wild populations; continuing survey efforts to identify new populations; increasing the area occupied by existing populations; establishing new populations; controlling threats such as habitat degradation and consumption of plants by feral pigs and competition with invasive introduced plants; and increasing knowledge of the species through research and monitoring.

Copies of the final recovery plan are available through the U.S. Fish and Wildlife Service’s website at www.fws.gov/pacificislands/ or by calling the U.S. Fish and Wildlife Service’s Honolulu office at (808) 792-9400.

* Lee Imada can be reached at leeimada@mauinews.com.