Recovery Plan for the Oahu Plants Kaena Point RECOVERY PLAN FOR THE OAHIJ PLANTS Published by U.S. Fish and Wildlife Service Portland, Oregon Approved: Regional Director, U.S. Fish & dlife ice Date: I DISCLAIMER PAGE Recovery plans delineate reasonable actions that are believed to be required to recover and/or protect listed species. Plans are published by the U.S. Fish and Wildlife Service, sometimes prepared with the assistance ofrecovery teams, contractors, State agencies, and others. Objectives will be attained and any necessary funds made available subject to budgetary and other constraints affecting the parties involved, as well as the need to address other priorities. Costs indicated for task implementation and/or time for achievement ofrecovery are only estimates and are subject to change. Recovery plans do not necessarily represent the views nor the official positions or approval ofany individuals or agencies involved in the plan formulation, otherthan the U.S. Fish and Wildlife Service. They represent the official position ofthe U.S. Fish and Wildlife Service ~n1yafter they have been signed by the Regional Director or Director as approved. Approved recovery plans are subject to modification as dictated by new findings, changes in species status, and the completion ofrecovery tasks. Literature Citation: U.S. Fish and Wildlife Service. 1998. Recovery Plan for Oahu Plants. U.S. Fish and Wildlife Service, Portland, Oregon. 207 pp., plus appendices. ii ACKNOWLEDGMENTS The Recovery Plan for the Oahu Plants was prepared by Scott M. Johnston and revised by Christina M. Crooker, U.S. Fish & Wildlife Service (USFWS), Pacific Islands Ecoregion, Honolulu, Hawaii. Invaluable assistance was provided by Wendy Fulks, Joel Lau, Barrie Morgan, and Jennifer Crummer ofThe Nature Conservancy of Hawaii (TNCH), Cliff Smith ofthe Cooperative Park Studies Unit (CPSU), Myron Isherwood ofthe Hawaii Department ofAgriculture (HDOA), Melany Chapin, Sylvia Smith, Diane Ragone, Ken Wood, and Steve Perlman ofthe National Tropical Botanical Garden (NTBG), Randy Kennedy, Bill Garnett, Talbert Takahama, Bryon Stevens, Lyman Perry, and Bob Hobdy ofthe Division of Forestry and Wildlife (DOFAW), Kapua Kawelo (US Army), David Orr (Waimea Arboretum), Greg Koob (Lyon Arboretum), Marie Bruegmann, Elizabeth Sharpe, Loyal Mehrhoff, John Schmerfeld, Heather McSharry, Tanya Rubenstein, Ron Salz, Susan Machida, and Rod Low (USFWS) and John Obata, and Ron Fenstenmacher. iii EXECUTIVE SUMMARY Current Species Status: The Recovery Plan for the Oahu Plants covers 66 plant taxa, all of which are listed as endangered. This Recovery Plan combines the Koolau Mountain Plant Cluster (USFWS 1996a) and Waianae Mountain Plant Cluster (USFWS 1995) Recovery Plans with newly listed species (USFWS 1996b) for which a Recovery Plan has never been completed. The numbers ofknown remaining populations and individuals are as follows: TAXON POPULATIONS INDIVIDUALS Abutilon sandwicense 14 <300 Alsinidendron obovatum 4 12 Alsinidendron trinerve 3 108 Chamaesyce celastroides var. kaenana 10 545 Chamaesyce deppeana 1 <50 Chamaesyce herbstii 4 <200 Chamaesyce kuwaleana 3 2,000 Chamaesyce rockii 11 200 — 400 Cyanea acuminata 15 <100 Cyanea crispa 7 40 Cyanea grimesiana ssp. obatae 3 13 Cyanea humboldtiana 3 125—225 Cyanea koolauensis 22 <80 Cyanea longflora 3 200 — 220 Cyaneapinnatfida 1 1 Cyanea st. -johnii 6 40—50 Cyanea superba 1 5 Cyanea truncata no known populations 0 Cyrtandra crenata no known populations 0 Cyrtandra dentata 4 <70 Cyrtandra polyantha 2 5 Cyrtandra subumbellata 3 <50 Cyrtandra viridflora 4 21 Delissea subcordata 18 <80 Dielliafalcata 22 5,540 — 6,540 Diellia unisora 4 700 Dubautia herbstobatae 4 525 Eragrostisfosbergii 4 6 Eugenia koolauensis 8 <220 Gardenia mannii 28 70—100 Gouania meyenii 7 92 iv Gouania viiWolia 3 26 Hedyotis degeneri 3 32 Hedyotisparvula 4 220—235 Hesperomannia arborescens 15 <100 Hesperomannia arbuscula S 90 Labordia cyrtandrae 5 13 Lepidium arbuscula 10 <900 Lipochaeta lobata var. leptophylla 3 142 Lipochacta tenufolia 9 2,000 Lobelia gaudichaudji ssp. koolauensis 4 <280 Lobelia monostachya 1 8 Lobelia niihauensis 33 967 — 2,852 Lobelia oahuensis 11 110 Melicope lydgatei 3 <45 Melicope saint-johnii 6 <150 Myrsinejuddii 3 500 — 3,000 Neraudia angulata 15 110 Nototrichium humile 15 1,500— 1,600 Phlegmariurus nutans 3 4 Phyllostegia hirsuta 16 150—200 Phyllostegia kaalaensis 6 <40 Phyllostegia mollis 5 120—140 Prftchardia kaalae 5 130 Sanicula mariversa 2 75 Schiedea kaalae 7 13 Schiedea kealiae 4 300—500 Silene perlmanii no known populations 0 Stenogyne kanehoana no known populations 0 Tetramolopiumfilforme 5 1,550 Tetramolopium lepidotum ssp. lepidotum 3 44—63 Tetraplasandra gymnocarpa 17 <200 Trematolobe/ia singularis 3 165 Urera kaalae 10 44 Viola chamissoniana ssp. chamissoniana 6 257 Viola oahuensis 8 <180 Fifty-six ofthese taxa are endemic to the island ofOahu. The following taxa also have current populations outside of the island of Oahu: Gouania meyenii and Lobelia niihauensis on Kauai; Hesperomannia arborescens on Molokal and Maui; Hesperomannia arbuscula on West Maui; Nototrichium humile and Phyllostegia mo//is on East Maui; and Gouania vit~fo/ia on Hawaii. Historically, two of the taxa were known from Molokai (Eugenia koolauensis and Phyllostegia inollis), two from Lanai (Hesperomannia arborescens and Tetramolopium lepidotuin ssp. V lepidotum), and one each from Kauai (Phlegmariurus nutans), West Maui (Gouania vitifolia), Niihau (Lobelia niihauensis), and Hawaii (Gouania vitjfolia). Habitat Requirements and Limiting Factors: The 66 taxa included in this plan grow in a variety of vegetation communities (lowland and mesic forests, shrublands, and volcanic cliffs) elevation zones (coastal to high cliff faces), and moisture regimes (dry and wet). These taxa and their habitats have been variously affected or are currently threatened by one or more of the following: trampling, predation, and habitat degradation by feral or domestic animals (goats, pigs, and cattle); competition for space, light, water, and nutrients by introduced vegetation; loss of pollinators; introduced bird species; erosion of substrate produced by human- or animal-caused disturbance; recreational and agricultural activities; habitat loss from fires; disease; and predation by rats, insects, slugs, snails. In addition, due to the small number ofexisting individuals and their very narrow distributions, these taxa are subject to an increased likelihood ofextinction and/or reduced reproductive vigor from risk from random, naturally-occurring events. Recovery Objectives: The ultimate objective is delisting of all taxa. Interim and downlisting objectives are provided to stabilize extremely rare taxa and downlist the taxa to threatened status. Recovery ofthe Oahu plants should be pursued by establishing management units that use available resources efficiently to conserve not only these taxa, but their habitats as well. Recoverv Criteria Interim Objectives The interim objective is to stabilize all existing populations ofthe Oahu taxa. To be considered stable, eachtaxon must be managed to control threats (e.g., fenced) and be represented in an ex situ (at other than its original site, such as a nursery or arboretum) collection. In addition, a minimum total of3 populations ofeachtaxon should be documented on Oahu, and, if possible, at least one other island where they now occur or occurred historically. Each population must be naturally reproducing and increasing in number, with a minimum of 25 mature individuals per population for long-lived perennials (Eugenia koolauensis, Hesperomannia arborescens, Hesperomannia arbuscula, Melicope lydgatei, Melicope saint-johnii, Pritchardia kaalae, Tetraplasandra gymnocarpa, and Urera kaa/ae) and a minimum of50 mature individuals per population for short-lived perennials (Abutilon sandwicense, Alsinidendron obovatum, Alsinidendron trinerve, Chamaesyce celastroides var. kaenana, Chamaesyce deppeana, Chamaesyce herbstii, Chamaesyce kuwaleana, Chamaesyce rockii~ Cyanea acuminata, Cyanea crispa, Cyanea grimesiana ssp. obatae, Cyanea humboldtiana, Cyanea koolauensis, C’yanea longflora, Cyanea pinnatfida, C’yanea st. Johnii, Cyanea superba, Cyanea truncata, Cyrtandra crenata, Cyrtandra dentata, Cyrtandra vi : polyantha, Cyrtandra subumbellata, Cyrtandra viridflora, Delissea subcordata, Die//iafalcata, Die/ha unisora, Dubautia herbstobatae, Eragrostisfosbergii, Gardenia mannii, Gouania meyenii, Gouania vit~folia, Hedyotis degeneri, Hedyotis parvula, Labordia cyrtandrae, Lepidium arbuscula, Lipochaeta lobata var. leptophylla, Lipochaeta tenu~fo/ia, Lobelia gaudichaudii ssp. koo/auensis, Lobe/ia monostachya, Lobelia niihauensis, Lobelia oahuensis, Myrsine juddii, Neraudia angulata, Nototrichium humile, Phlegmariurus nutans, Phyllostegia hirsuta, Phy//ostegia kaalaensis, Phyl/ostegia mo/lis, Sanicula mariversa, Schiedea kaa/ae, Schiedea kea/iae, Silene perlmanii, Stenogyne kanehoana, Tetramo/opium fi/Worme, Tetramo/opium /epidotum ssp. lepidotum, Trematolobelia singu/aris, Vio/a chamissoniana ssp. chamissoniana, and Viola oahuensis). Downlisting Objectives For downlisting, a total offive to seven populations of each taxon should be documented on Oahu and at least one other island where they now occur or occurred historically. Each ofthese populations must be naturally reproducing, stable or increasing in number, and secure, with a minimum of 100 mature individuals per population for long-lived perennials and a minimum of300 mature individuals per population