9-29 9.6 Reintroduction and Augmentation 2 Given the historical trend of reduction in geographic range, numbers of populations, and 4 numbers of individuals of endangered taxa in Hawaii, one of the strategies in the stabilization of the Makua target taxa is reintroduction of individuals into suitable managed habitat within the 6 known historical range or likely suitable habitat of a taxon. Reintroduction is defined in this plan as establishing a number of individuals into a geographic area within a taxon’s historic 8 range that is currently not known to contain the taxon, with the express purpose of establishing a sustained or growing population. The plant reintroduction and augmentation strategies presented 10 in the Implementation Plan (IP) are based on other efforts, including the Hawaii Rare Plant Restoration Group (HRPRG) reintroduction guidelines (see Section 3, Appendix 1.2: HRPRG 12 Reintroduction Guidelines) and the Makua Endangered Species Stabilization Plan Appendix: Reintroduction for Mitigation – Justification and Guidelines (U.S. Army 1999). 14 Most of the target taxa have declined to such levels that threat management alone will not allow 16 return of the taxa to stable levels. Reintroduction supports the primary strategy of active in situ management of extant wild populations toward stability. While reintroduction might be 18 necessary to achieve stability, activities involved in reintroduction can be extremely harmful unless care is taken to minimize impacts such as damage to habitat or other native taxa via 20 trampling, introduction of disease and alien taxa, and genetic contamination of target taxa or other native taxa. As part of this preventative approach, a list of particularly sensitive rare taxa 22 in the Waianae Region was developed (see Table 9.8), so that their presence at or near any proposed in situ management site will trigger assessments of strategies needed to alleviate 24 potential harm. 26 Reintroduction must be distinguished from augmentation, which involves the addition of individuals to a geographic area that is currently known to contain the taxon. The express 28 purpose of an augmentation is to increase the number of individuals in a population to enhance the possibility of cross-pollination between the plants. It is also used to increase the genetic 30 variability of the population by introducing individuals that bring new alleles into the population that may have become lost over time as the population declined. A major concern in 32 augmentation lies in the increased potential to negatively impact the genetic makeup of the pre- existing population. This is discussed in more detail below. 34 Genetic considerations 36 It is important to carefully consider potential genetic consequences when choosing individuals for use in reintroduction and augmentation. Reintroduction and augmentation can be carried out 38 using plants from a single source or by mixing plants from more than one source. Each strategy may have both positive and negative consequences and the risks of each must be carefully 40 balanced. 42 When a large and healthy source population is available, it is generally wise to use a variety of individuals from a single source for reintroduction. For such a population, it can be assumed that 44 genetic problems such as inbreeding are not manifested and will likely produce a genetically healthy reintroduction. 46 Final DACA83-96-D-0007/0055 Implementation Plan for Makua Military Reservation, Island of Oahu Chapter 9.6 Reintroduction and Augmentation 9-30 Table 9.8 Rare Plant Taxa Found in the Waianae Range. Taxa are listed as 48 endangered (E), considered for listing as threatened or endangered (C) by the U.S. Fish and Wwildlife Service, or identified as species of concern (SOC), and have less than 500 individuals 50 globally; or non-listed species (NS) with less than 5 known population units and less than 1,000 individuals globally. Federal Taxon Name Family Common Name Status Abutilon menziesii Malvaceae kooloaula E Abutilon sandwicense Malvaceae no common name E Achyranthes splendens var. rotundata Amaranthaceae no common name E Alectryon macrococcus var. macrococcus Sapindaceae mahoe E Alsinidendron obovatum Caryophyllaceae no common name E Alsinidendron trinerve Caryophyllaceae no common name E Bobea timonioides Rubiaceae ahakea SOC Bobea sandwicensis Rubiaceae ahakea SOC Bonamia menziesii Convolvulaceae no common name E Caesalpinia kavaiensis Fabaceae uhiuhi E Cenchrus agrimonioides var. agrimonioides Poaceae kamanomano, umealu E Centaurium sebaeoides Gentianaceae awiwi E Chamaesyce celastroides var. kaenana Euphorbiaceae akoko E Chamaesyce herbstii Euphorbiaceae akoko E Colubrina oppositifolia Rhamnaceae kauila E Ctenitis squamigera Dryopteridaceae pauoa E Cyanea acuminata Campanulaceae haha E Cyanea calycina Campanulaceae haha C Cyanea grimesiana subsp. grimesiana Campanulaceae haha E Cyanea grimesiana subsp. obatae Campanulaceae haha E Cyanea longiflora Campanulaceae haha E Cyanea pinnatifida Campanulaceae haha E Cyanea superba subsp. superba Campanulaceae haha E Cyperus pennatiformis subsp. pennatiformis Cyperaceae no common name E Cyperus trachysanthos Cyperaceae puukaa E Cyrtandra dentata Gesneriaceae haiwale E Cyrtandra rivularis Gesneriaceae haiwale SOC Delissea subcordata Campanulaceae no common name E Diellia unisora Aspleniaceae no common name E Diplazium molokaiense Athyriaceae no common name E Dubautia sherffiana Asteraceae naenae SOC Eugenia koolauensis Myrtaceae nioi E Exocarpos gaudichaudii Santalaceae heau SOC Flueggea neowawraea Euphorbiaceae mehamehame E Gardenia brighamii Rubiaceae nanu E Gardenia mannii Rubiaceae nanu E Final DACA83-96-D-0007/0055 Implementation Plan for Makua Military Reservation, Island of Oahu Chapter 9.6 Reintroduction and Augmentation 9-31 Federal Taxon Name Family Vernacular Name Status Gouania meyenii Rhamnaceae no common name E Gouania vitifolia Rhamnaceae no common name E Hedyotis coriacea Rubiaceae kioele E Hedyotis degeneri var. coprosmifolia Rubiaceae no common name E Hedyotis degeneri var. degeneri Rubiaceae no common name E Hedyotis parvula Rubiaceae no common name E Hesperomannia arborescens Asteraceae no common name E Hesperomannia arbuscula Asteraceae no common name E Hibiscus brackenridgei subsp. Malvaceae mao hau hele E mokuleianus Isodendrion laurifolium Violaceae aupaka E Isodendrion pyrifolium Violaceae aupaka; wahine noho kula E Joinvillea ascendens subsp. ascendens Joinvilleaceae ohe C Labordia cyrtandrae Loganiaceae kamakahala E Lipochaeta lobata var. leptophylla Asteraceae nehe E Lobelia oahuensis Campanulaceae no common name E Lobelia sp. (related to L. hypoleuca in West Campanulaceae no common name NS Range of Schofield Barracks) Melicope christophersenii Rutaceae alani C Melicope makahae Rutaceae alani C Melicope pallida Rutaceae alani E Melicope saint-johnii Rutaceae alani E Myoporum stellatum Myoporaceae naio, bastard sandalwood SOC Neraudia angulata var. angulata Urticaceae no common name E Neraudia angulata var. dentata Urticaceae no common name E Nesoluma polynesicum Sapotaceae keahi SOC Nothocestrum latifolium Solanaceae aiea C Phyllostegia hirsuta Lamiaceae no common name E Phyllostegia kaalaensis Lamiaceae no common name E Phyllostegia mollis Lamiaceae no common name E Phyllostegia parviflora var. lydgatei Lamiaceae no common name E Plantago princeps var. princeps Plantaginaceae ale E Platydesma cornuta var. decurrens Rutaceae no common name C Pleomele forbesii Agavaceae halapepe C Pritchardia kaalae Arecaceae loulu E Pritchardia sp. (related to P. martii in North Arecaceae loulu NS Palawai Gulch, Honouliuli Preserve) Pteralyxia macrocarpa Apocynaceae kaulu C Ranunculus mauiensis Ranunculaceae makou C Sanicula mariversa Apiaceae no common name E Scaevola coriacea Goodeniaceae dwarf naupaka E Final DACA83-96-D-0007/0055 Implementation Plan for Makua Military Reservation, Island of Oahu Chapter 9.6 Reintroduction and Augmentation 9-32 Federal Taxon Name Family Vernacular Name Status Schiedea hookeri Caryophyllaceae no common name E Schiedea kaalae Caryophyllaceae no common name E Schiedea kealiae Caryophyllaceae no common name E Schiedea nuttallii Caryophyllaceae no common name E Schiedea pentandra Caryophyllaceae no common name SOC Sicyos lanceoloidea Cucurbitaceae anunu SOC Sicyos waimanaloensis Cucurbitaceae anunu SOC Solanum nelsonii Solanaceae popolo C Solanum sandwicense Solanaceae popolo aiakeakua E Stenogyne kanehoana Lamiaceae No common name E Tetramolopium filiforme var. polyphyllum Asteraceae no common name E Tetramolopium lepidotum subsp. lepidotum Asteraceae no common name E Urera kaalae Urticaceae opuhe E Vigna o-wahuensis Fabaceae no common name E Viola chamissoniana subsp. chamissoniana Violaceae pamakani, olopu E 52 54 Large healthy populations are not always available. In these situations, the risks of mixing versus using a single source must be weighed. For normally outcrossing plants with small 56 populations, random genetic drift may play a larger role in the genetic structure of a population than natural selection. The consequence of this is often a reduction in fitness known as 58 inbreeding depression. Such a reduction in fitness occurs because inbreeding increases homozygosity, which may lead to the expression of recessive deleterious alleles. In addition, an 60 inbred population may lack the allelic diversity required for a population to change gene frequencies in order to adapt to a changing environment over time. Small population size and 62 inbreeding are not necessarily