Fun Facts about PTA's Listed Species
Background
PTA includes a portion of the last remaining sub-alpine tropical dryland ecosystem in the world. There are 20 federally-listed species found at the installation (16 plants and 4 animals).
There are 16 federally-listed plant species at the installation, 1 plant species that is a candidate for federal listing, and 1 plant species that is undescribed and not federally-listed but is managed due to its rarity and limited distribution. Several of these plant species occur almost exclusively on the installation.
One federally-listed mammal species and 2 federally-listed bird species are known to occasionally use habitat at PTA. Additionally, it is possible that 1 federally-listed sea bird species and 1 sea bird species that is a candidate for federal listing may periodically transit the installation.
Fifteen bird species protected under the Migratory Bird Treaty Act are known to occur at PTA and KMA.
Hawai‘i is the most isolated island chain in the world, standing 2,500 miles away from the nearest continent. Native plants, insects and birds crossed the Pacific to get here, and most of their natural predators did not travel with them. In many cases, the plants and insects of Hawai‘i lost their thorns and chemical defenses.
Due to these decreased defenses, introduced feral ungulates have decimated rare plant populations at PTA. Other threats to ecosystem health at the installation come from changes to the landscape as a result of invasive plants and wildland fire.
PTA includes a portion of the last remaining sub-alpine tropical dryland ecosystem in the world. There are 20 federally-listed species found at the installation (16 plants and 4 animals).
There are 16 federally-listed plant species at the installation, 1 plant species that is a candidate for federal listing, and 1 plant species that is undescribed and not federally-listed but is managed due to its rarity and limited distribution. Several of these plant species occur almost exclusively on the installation.
One federally-listed mammal species and 2 federally-listed bird species are known to occasionally use habitat at PTA. Additionally, it is possible that 1 federally-listed sea bird species and 1 sea bird species that is a candidate for federal listing may periodically transit the installation.
Fifteen bird species protected under the Migratory Bird Treaty Act are known to occur at PTA and KMA.
Hawai‘i is the most isolated island chain in the world, standing 2,500 miles away from the nearest continent. Native plants, insects and birds crossed the Pacific to get here, and most of their natural predators did not travel with them. In many cases, the plants and insects of Hawai‘i lost their thorns and chemical defenses.
Due to these decreased defenses, introduced feral ungulates have decimated rare plant populations at PTA. Other threats to ecosystem health at the installation come from changes to the landscape as a result of invasive plants and wildland fire.
Plants:
Hawaiian mint, honohono (Haplostachys haplostachya)
This endangered mint appears to be fire resistant. The success of H. haplostachya following fire events is due to its ability to resprout and its frequent location on rocky slopes. Fires in rocky areas tend to occur at low and moderate intensities because of low fuel loads. |
ʻAupaka (Isodendrion hosakae)
This endangered shrub in the violet family is found on steep cinder cones in the South Kohala District on the island of Hawaiʻi. Its habitat is surrounded by converted pasture lands. In the absence of grazing pressures from cattle and feral ungulates, I. hosakae would presumably be more widely distributed. |
Leather-leaf sweet ear, kioʻele (Kadua coriacea)
Due to its extreme rarity, the reproductive biology for this endangered plant in the coffee family is poorly understood. In past years, an unexplained lack regeneration has been observed for K. coriacea despite the fact that the majority of adults were reproductively active. However, several seedlings were recently discovered at PTA. |
Nehe (Melanthera venosa)
The endangered plant in the sunflower family is endemic to the island of Hawaiʻi. M. venosa is typically found on the stony soils of cinder cones in montane dry shrublands dominated by non-native grasses and some native shrubs. This species is known to rootsprout and can recolonize areas following fire events. |
Spotted nettle bush, maʻaloa (Neraudia ovata)
Individuals of this endangered nettle may be somewhat variable in their phenology. Limited observations suggest plants are not truly dioecious, but consecutively monoecious, bearing male and female flowers at different times on the same plant. This variability may occur from year to year. |
Hard fruit purslane, poʻe (Portulaca sclerocarpa)
This endangered herb in the purslane family grows on weathered Mauna Kea soils, cinder cones, geologically young lavas in montane dry shrublands, and in open woodlands. P. sclerocarpa is currently found at Hawaiʻi Volcanoes National Park (HAVO) and PTA. Unfortunately, 90% of known individuals were lost in 2008 after a major decline in the HAVO population. |
Maʻoilʻoli (Schiedea hawaiiensis)
This sprawling vine in the pink family was listed as endangered in 2013. The last known wild S. hawaiiensis on earth existed at PTA. It was fenced to protect it from ungulate browse and managed to prevent rodent predation. The last adult S. hawaiiensis has since died, but it left behind several seedlings that have matured and are currently being propagated and outplanted. |
Hawaiian catchfly (Silene hawaiiensis)
Endemic to the island of Hawai‘i, S. hawaiiensis is a threatened shrub in the pink family that is highly palatable to feral ungulates. However, the species appears to be relatively hardy, perhaps due to its ability to resprout from the large fleshy taproot. S. hawaiiensis has also been documented to resprout following a fire event. |
Lance-leaf catchfly (Silene lanceolata)
The showy white flowers on this endangered shrub in the pink family have a sticky base that "catch" invertebrates such as ants and flies. S. lanceolata is capable of establishing itself successfully in a wide range of habitats and in plant communities growing on very old substrates or very young lava flows. |
Hawaiian prickle leaf, pōpolo kū mai (Solanum incompletum)
For over half a century, this endangered nightshade was thought to be extinct until it was rediscovered at PTA in 1996. It is currently found in 3 locations at the installation. S. incompletum is one of the few native Hawaiian plant species that has developed spiny reddish-orange prickles as a defense mechanism....ouch! |
Hawaiian parsley (Spermolepis hawaiiensis)
This endangered parsley has an annual life cycle. At PTA, S. hawaiiensis is heavily dependent upon rainfall to carry out its life cycle. Large recruitment events have been observed after periods of above average rainfall. Based on observations, it is likely that this species does not germinate at all during long periods of inadequate rainfall. |
Creeping mint (Stenogyne angustifolia var. angustifolia)
Mint is a chemical mechanism plants evolved to defend against predators. However, here in Hawai‘i, dozens of mint species have lost this defense due to the isolated location of the islands and the lack of natural predators. The endangered S. angustifolia is considered to be one of these "mintless" mints. |
Mauna Kea pamakani (Tetramolopium arenarium ssp. arenarium var. arenarium)
This endangered plant in the sunflower family is extremely rare and only occurs in a few locations at PTA. Following severe drought conditions, the T. arenarium ssp. arenarium var. arenarium population declined to just 12 individuals in 2010. Currently, the population is now fairly stable at about 600. |
Oʻahu cowpea (Vigna o-wahuensis)
This endangered legume is endemic to Hawaiʻi. Though V. o-wahuensis was described from a specimen collected on Oʻahu, it is now extirpated from that island; there are currently fewer than 100 individuals total remaining on 5 main islands. This species grows in shrubland and grassland habitat on cinder cones, offshore islets, and exposed coral reefs. |
Hawaiian yellow wood, aʻe (Zanthoxylum hawaiiense)
In 2009 and 2010, extreme drought conditions at PTA led to an increase in ungulate pressure to rare plants and their habitat. NRO biologists observed significant bark stripping on the endangered Z. hawaiiense and an emergency management response (i.e., tree protectors) was initiated. Since then, large-scale fences have been constructed and ungulate removal almost complete. |
Animals:
Hawaiian goose, nēnē (Branta sandvicensis)
This endangered goose is the state bird of Hawaiʻi. It is believed that B. sandvicensis was once common, with ~25,000 geese living in Hawaiʻi when Captain James Cook arrived in 1778. Hunting and introduced predators reduced the population to 30 birds by 1952. The species breeds well in captivity and has been successfully re-introduced; in 2012, the statewide population was estimated to be ~2,500 birds. |
Hawaiian hawk, ʻīo (Buteo solitarius)
This endangered raptor is endemic to Hawaiʻi and was a symbol of royalty in Hawaiian legend. B. solitarius is mostly solitary, remaining in and defending its territories year round. During the nestling period, females perform most of the brooding while males provide food to chicks and females. After the egg is hatched, the female only allows the male to visit when delivering food to the nest. |
Hawaiian hoary bat, ʻōpeʻapeʻa (Lasiurus cinereus semotus)
This endangered bat is the only native land mammal in Hawaiʻi. This bat's common name was inspired by the hoary or "frosty" appearance of its fur, which is brown but frosted white on its back. L. cinereus semotus is a nocturnal insectivore. It finds food through echolocation, meaning it emits calls and listens to their echoes. |
Hawaiian petrel, ʻuʻau (Pterodroma sandwichensis)
This endangered petrel nests on land in burrows or rock crevices but feeds out at sea. Scientists previously thought that petrels remained close to shore, but new research shows they travel as far as Alaska and Japan during 2-week long feeding trips. Their diet consists of squid, fish, and crustaceans. |