Hawaii Cooperative Studies Unit (HCSU)

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Rapid assessment of invertebrate fauna of the Kona Forest Unit of Hakalau National Wildlife Refuge.
(2005-09) Haines, William; Foote, David
This report details a large, but preliminary, collection of insects from the Kona Forest Unit of the Hakalau National Wildlife Refuge. Visits to the Refuge were carried out by vehicle from July 1999 until October 2000 when the survey was interrupted by loss of road access to the Refuge. The purpose of this survey was to inventory endemic insect taxa likely to respond to future forest restoration efforts, including the removal of feral ungulates from the Refuge. Additionally, selected alien insect species were also collected. Before the inventory was undertaken, 296 historical species records were compiled for the South Kona region. Using this list and other summaries for the Island of Hawai‘i, nine groups of endemic insects were targeted, including 4 genera of beetles; pomace flies; yellow-faced bees; 2 genera of moths; and Hawaiian damselflies. These target groups were chosen because species richness within these taxa increases the opportunity for documenting changes in native insect communities as a consequence of resource management activities. Many of these groups also contain Fish and Wildlife Species of Concern or Candidate Endangered Species. Survey work was initiated over 750 m long contour transects at 500 m intervals between 762 m and 1,676 m elevation. A total of 1,683 specimen lots comprising a total of 9,330 individual specimens were collected and analyzed. Among alien invertebrates of concern that were detected, yellowjacket wasps were widely established in the refuge and their populations underwent seasonal outbreaks typical of other mesic forest populations on the island. Three scientific publications so far have directly resulted from the analysis of native insect taxa from the Refuge and specimen data has also contributed to one comprehensive taxonomic monograph. One interesting finding is the occurrence of the ‘ohe leafroller, Omiodes asaphombra, at light traps on the refuge. This endemic moth was once thought to be extinct and has only been found breeding on ‘ohe, or Joinvillea ascendens. This indigenous plant is very rare on the island of Hawaii and has not been recorded from the refuge or anywhere on the west side of the island. The most significant finding of this project was the discovery of a population of the rare picture-wing pomace fly, Drosophila heteroneura. Drosophila heteroneura is a Candidate Endangered Species found only on the Island of Hawai‘i. Images of the hammer-headed males of this pomace fly have frequently been used to illustrate the uniqueness of Hawai‘i’s insect fauna and D. heteroneura has been one of the most intensively researched native insects in the state. However, the fly now appears to be extirpated from all of its previously known historical range. The observations of D. heteroneura on the Refuge are the first observations of this species in the wild in approximately ten years. As of 1999, the Refuge supported the only known extant population of this unique Hawaiian picture-wing fly. It is recommended that management of the Kona Forest Unit to foster preservation of this and other rare Hawaiian insects should include suppression of alien yellowjacket wasps.
Hanalei Bay, Kaua`i marine benthic communities since 1992: spatial and and temporal trends in a dynamic Hawaiian coral reef ecosystem
(2006-02) Friedlander, Alan M.; Brown, Eric K.
Hanalei Bay, Kaua‘i is situated in a dynamic and relatively harsh environment that at times includes high wave energy, heavy fresh water influx, and high turbidity. These conditions result in overall low coral cover (ca. 14%) that is dominated by encrustingforms adapted to high wave energy. The five most abundant coral species in 1993 were Montipora patula (7%), M. capitata (2%), Porites lobata (2%), P. compressa (1%), and Pocillopora meandrina (1%). Average percent coral cover increased non-linearly among 20 permanent transects in Hanalei Bay from 1993 to 2004. Between 1993 and 1999 there was an increase of 5% absolute (34% relative) in live coral cover from 14% to 19%. From 1999 to 2004 coral cover remained relatively stable. Much of the initial increase was attributed to Montipora patula which increased in percent cover from 7% in 1993 to 11% in 2004. Species composition patterns remained similar during that time period. Coral settlement in 2003 and 2004 was higher in the outer bay compared to locations in the inner bay. Coral recruits were dominated by the genus Montipora that typically has high recruitment rates but low survival compared to other coral genera. Coral larval settlement was observed to be higher in Hanalei Bay compared to other regions around the world and may help explain the increase in coral cover observed over the past decade. Temporal variability, artificial substrate type used, or observer biases, however, could all effect documented settlement patterns, therefore these patterns may not be directly influenced by increases in coral cover. Fish species richness, biomass, and diversity were higher in habitats with high spatial relief adjacent to reef-sand interfaces. Most measures of fish assemblage structure were lower during the winter months when large north Pacific swells and heavy rainfall, coupled with high river discharge, impacted the bay. Fish assemblage characteristics did not vary significantly between 1993 and 2004 although trends in biomass are suggestive of an increase over time. Three introduced fish species (bluestripe snapper, blacktail snapper, and peacock grouper) have become well established in Hanalei Bay and their contribution to total fish biomass has increased from 15% in 1993 to as high as 39% in 1999. Hanalei Bay is one of the few areas in Hawaii that has shown an increase in live coral cover over the past decade. Increases in total fish biomass since the early 1990s cannot be attributed solely to introduced species, as other elements of the fish assemblage have also increased over this time period. Natural factors such as large wave events are thought to be more important in structuring the coral reef community of Hanalei Bay than anthropogenic factors, and this may help to explain the trends observed in this study.
Natural resources management needs for coastal and littoral marine ecosystems of the U.S. affiliated pacific islands: American Samoa, Guam, Commonwealth of the Northern Marianas Islands, Republic of the Marshall Islands, Federated States of Micronesia and the Republic of Palau.
(2006-11) Haws, Maria
This report presents a summary of the research and management needs for natural resources of the U.S. Affiliated Pacific Islands. These islands include three island groups which are affiliated politically with the U.S., Commonwealth of the Northern Marianas, Guam, American Samoa and three independent nations which are freely affiliated with the U.S, the Republic of Palau, Federated States of Micronesia and the Republic of the Marshall Islands. This work is intended to orient the U.S. Geological Survey Pacific Island Ecosystems Research Center’s (PIERC) biological research to support management of natural resources in coastal and littoral marine ecosystems (CLME) in Hawaii and the U.S. Affiliated Pacific Islands. Although the focus of PIERC is on natural resources under stewardship of the Federal government and its local partners (including National Parks, United States Fish and Wildlife Services (USFWS) Refuges, National Oceanic and Atmospheric Administration (NOAA) sanctuaries and reserves, State reserves and protected areas), research and management activities may be conducted in any Pacific basin location that provides information essential to management and conservation of CLM ecosystems. Moreover, science may address issues that span the waterline, that is, research may be required in both terrestrial and aquatic habitats in order to fully describe, understand, and predict the impact of resource management and usage on various components of the marine and coastal ecosystems.
Efficacy of feral pig removals at Hakalau Forest National Wildlife Refuge.
(2006-12) Hess, Steven C.; Jeffrey, John J.; Ball, Donna L.; Babich, Lev
We compiled and analyzed data from 1987–2004 on feral pig (Sus scrofa) management and monitoring activities at Hakalau Forest National Wildlife Refuge, a tropical montane rainforest on the island of Hawai`i. These data included annual surveys of feral pig and cattle (Bos taurus) activity, the number of feral ungulates removed from closed management units, age and reproductive status from necropsies, and vegetation surveys repeated 4 times over a 16 year period. We found an essentially even sex ratio within the feral pig population and within age classes, although males lived to 60 months while females lived to only 48 months. The pregnancy rate was 23.5%, and lactation rate was 8.3%, regardless of season and age, but lactation peaked in April-June. Reproductive rates also increased with age, peaking at 2–4 years in females. We reconstructed the standing population within a closed unit to examine demographic processes. We estimated that annual removal in excess of approximately 41–43% would be necessary to affect a population decline. We examined annual feral pig activity surveys and found a strong and sustained decline in pig sign after 1997 relative to unmanaged areas. We related the standing population to feral pig activity surveys to build a predictive model of feral pig density, and then applied this model to other management units. We evaluated control methods and found snaring to be more efficient than staff or public hunting. Vegetation monitoring revealed a strong temporal increase in cover of native ferns, and marginally non-significant decreases in cover of bryophytes and exposed soil.
Measurement errors in Hawaiian forest bird surveys and their effect on density estimation.
(2007-03) Camp, Richard J.
Reliable count data are necessary for valid density estimation. Before each Hawaiian bird survey, observers go through a training and calibration exercise where they record measurements from a station center point to flagging placed about the station. The true distances are measured, and when an observer's measurements are within 10% of truth the observer is considered calibrated and ready for surveying. Observers tend to underestimate distances, especially for distant measures (e.g., true distance > 50 m). All proposed empirical distribution functions failed to adequately identify the function form of the calibration data. The effect of measurement errors were assessed with populations of known density in a simulation study. By simulations, using the true distances, the conventional estimator seems unbiased; however, in the presence of measurement errors the estimator is biased upward, resulting in overestimated population sizes. More emphasis should be made to minimize measurement errors. Observers’ measurement errors should be small with deviances less than 10%, for example, and observers should recalibrate frequently during surveys. Truncation is not a surrogate for increased accuracy. When there are relatively large amounts of measurement error estimators to correct the errors should be developed and used. Measurement errors to birds heard but not seen needs to be calibrated, and adjustment parameters included in measurement error correction models.
Seabird Monitoring assessment for Hawai`i and the Pacific Islands
(2007-10) Citta, John; Reynolds, Michelle H.; Seavey, Nathaniel E.
This document is an assessment of the seabird monitoring program for the United States Pacific Islands (USPI) within the Pacific Region of the US Fish and Wildlife Service (USFWS). This area includes America Samoa, the Phoenix Islands, Palmyra Atoll, Johnston Atoll, Wake Atoll, the Mariana Islands, and the Main and Northwestern Hawaiian Islands. This report was requested by the USFWS to assist in the development of a scientifically sound seabird monitoring program for this region. In this report, we review monitoring methods, analyze existing USFWS data to evaluate the statistical power of current monitoring, and propose recommendations for statistically rigorous seabird monitoring protocols.
Rapid assessment of vegetation at six potential `Alala release sites on the island of Hawai`i
(2007-10) Price, John P.; Jacobi, James D.
The U.S Fish and Wildlife Service (FWS), as part of its participation in the effort to recover the endangered ‘Alalā (Corvus hawaiiensis), is supporting efforts by the ‘Alalā Recovery Team (ART) to rank areas for suitability as reintroduction sites for this species. A part of this ranking exercise is determination of the current state of the vegetation present at the sites. Although some of these sites have been surveyed using various methods in the recent past, specific, comparable measurements of key aspects of the plant communities are needed for ranking sites for ‘Alalā recovery. Here we summarize new and compiled data for each of the release sites that address the current status and potential recovery of the tree canopy and understory vegetation relative to potential suitability for ‘Alalā release. This project focused on two objectives: 1) Assess the current status and distribution of forest canopy cover based on an analysis of recent satellite imagery and other spatial datasets, and 2) Collect new field data from the six potential release sites to provide quantitative information on the status of the vegetation, with particular focus on density and species composition of plants used by ‘Alalā as food, overall density of forest understory, and degree of closure of tree canopy. The field data also served as ground-truth points for the spatial analysis. The methods of assessing habitat potential for ‘Alalā recovery presented here represent a simple measure of vegetation attributes taken from a limited number of plots within each study area. A primary problem is in attempting to summarize large study areas that incorporate considerable variation in climate, substrate, and land use history. An examination of several versions of the preferred food species richness value ranks the two Ka‘ū study sites first and second. This study does not consider the amount of fruit produced by different species, and therefore it is possible that some additional weighting of preferred food plants might better quantify food resource availability in different landscapes. We also assessed continuity of forest units with other similar habitats outside the study areas, the amount of site disturbance as indicated by percent cover by alien grass species, as well as several other combinations of variables that may help in ranking the sites.
Mapping plant species ranges in the Hawaiian Islands: developing a methodology and associated GIS layers.
(2007-11) Price, John P.; Gon III, Samuel M.; Jacobi, James D.; Matsuwaki, Dwight
This report documents components of a methodology for projecting the geographic ranges of plant species in the Hawaiian Islands. This consists primarily of the creation of several GIS data layers depicting attributes related to the geographic ranges of plant species. The most important data layer generated here is an objectively-defined classification of climate as it pertains to the distribution of plant species. By examining previous zonal vegetation classifications in light of spatially detailed climate data, we explicitly define broad zones of climate relevant to contemporary concepts of vegetation in the Hawaiian Islands. A second spatial data layer presented here considers substrate age, since large areas of the island of Hawai‘i in particular are covered by very young lava flows, which are inimical to the growth of many plant species. The third data layer presented here divides larger islands, which are composites of multiple volcanoes, into definable biogeographic regions, since many species are restricted to a given topographically isolated mountain or a specified group of these. A final spatial data layer depicts human impact, which reduces the range of many species relative to where they formerly occurred. Several other factors that influence the geographic ranges of species, including topography, soils, and disturbance, are discussed here but not developed further due to limitations in rendering them spatially. We describe a method for analyzing these base layers in a geographic information system (GIS), in conjunction with a database of species distributions, to project the ranges of plant species, including the potential range prior to human disturbance and the projected present range. Examples of range maps for several species are given as case studies that demonstrate different spatial characteristics of range. We discuss several potential applications of species range maps including facilitation of field surveys, informing restoration efforts, studies of range size and rarity, studies of biodiversity, conservation planning, and invasive species management.
Abundance, distribution, and population trend of the Hawaiian Hawk; 1998-2007.
(2008-04) Gorresen, P. Marcos; Camp, Richard J.; Klavitter, John L.; Pratt, Thane K.
The current population size and distribution of the endemic Hawaiian Hawk (or`Io in Hawaiian, Buteo solitarius) on Hawai`i Island was determined as part of a reevaluation of the species’ endangered status. Locations originally sampled in 1998 were resurveyed in 2007 with variable circular plot (VCP) count methods to produce habitat-specific estimates of density and assess trends in abundance. In addition, we developed a method for correcting density estimates for the unobserved movement of hawks attracted to call playbacks. We estimated that the 5,755 km2 breeding range harbored 3,239 hawks (95% CI = 2,610 to 3,868) in 1998 and 3,085 hawks (95% CI = 2,496 to 3,680) in 2007. No significant difference in densities was found among years at either regional or island-wide scales. However, pooled 1998 and 2007 densities did show significant differences among habitats and regions. Our 1998 and 2007 population estimates are as much as twice that of previous estimates, and we discuss reasons for this including differences among studies in the accuracy of distance estimation, accounting for unobserved hawk movement, and the extent of area used for the extrapolation of mean densities. The Hawaiian Hawk appears to persist as a viable population well-distributed throughout forest and adjacent habitats on Hawai`i Island. However, with a population comprised of about 3,000 individuals confined to a single island, the species is vulnerable to the effects of human-caused change to its habitat base.
Reducing feral cat threats to native wildlife in Hawai`i
(2008-07) Hess, Steven C.; Hansen, Heidi; Banko, Paul C.
We documented the diet of feral cats (Felis catus) on Kīlauea and Mauna Loa within Hawai`i Volcanoes National Park (HAVO), determined the incidence of three feline diseases on Mauna Kea, studied feral cat home range, developed and tested trap-signaling devices, tested food-based baits and attractants, analyzed feral cat population dynamics using genetic techniques, and developed an adaptive strategy for reducing predation on endangered Hawaiian birds. We documented the diet of feral cats by analyzing the contents of 42 digestive tracts from Kīlauea and Mauna Loa in Hawai`i Volcanoes National Park. Small mammals, invertebrates, and birds were the most common prey types consumed by feral cats. Birds occurred in 27.8–29.2% of digestive tracts. The total number of bird, small mammal, and invertebrate prey differed between Kīlauea and Mauna Loa. On Mauna Loa, significantly more (89%) feral cats consumed small mammals, primarily rodents, than on Kīlauea Volcano (50%). Mice (Mus musculus) were the major component of the feral cat diet on Mauna Loa, whereas Orthoptera were the major component of the diet on Kīlauea. We recovered a mandible set, feathers, and bones of an endangered Hawaiian Petrel (Pterodroma sandwichensis) from a digestive tract from Mauna Loa. This specimen represents the first well-documented endangered seabird to be recovered from the digestive tract of a feral cat in Hawai`i and suggests that feral cats prey on this species. We determined prevalence to feline immunodeficiency virus (FIV) antibodies, feline leukemia virus (FeLV) antigen, and Toxoplasma gondii antibodies in feral cats on Mauna Kea Hawai`i from April 2002 to May 2004. Six of 68 (8.8%) and 11/68 (16.2%) were antibody positive to FIV and antigen positive for FeLV, respectively; 25/67 (37.3%) were seropositive to T. gondii. Antibodies to FeLV and T. gondii occurred in all age and sex classes, but FIV occurred only in adult males. Evidence of previous or current infections with two of these infectious agents was detected in eight of 64 cats (12.5%). Despite exposure to these infectious agents, feral cats remain abundant throughout the Hawaiian Islands. Feral cats in dry subalpine woodland of Mauna Kea, Hawai`i, live in low density and exhibit some of the largest reported home ranges in the literature. While 95% fixed kernel home range estimates for three females averaged 772 ha, four males averaged 1,418 ha, and one male maintained a home range of 2,050 ha. Mean daily movement rates between sexes overlapped widely and did not differ significantly (P = 0.083). Log-transformed 95% kernel 2 home ranges for males were significantly larger than those of females (P = 0.024), but 25% kernel home ranges for females were larger than those of males (P = 0.017). Moreover, logtransformed home ranges of males were also significantly larger than those of females in this and seven other studies from the Pacific region (P = 0.044). Feral cats present a major threat to endangered Hawaiian birds, but knowledge of their ecology can be used for management by optimizing trap spacing and creating buffer zones around conservation areas. Frequent checks of live traps require enormous amounts of labor and add human scents associated with repeated monitoring which may reduce capture efficiency. To reduce efforts and increase efficiency, we developed a trap-signaling device with long-distance reception, durability in adverse weather, and ease of transport, deployment, and use. Modifications from previous designs include a normally-open magnetic switch and a mounting configuration to maximize reception. The system weighed < 225 g, was effective ≤ 17.1 km, and failed in < 1% of trap-nights. Employing this system, researchers and wildlife managers may reduce the amount of effort checking traps while improving the welfare of trapped animals. Successful feral cat control programs require effective baits and lures. Non-targets may interfere with trapping efforts by rapidly consuming bait before feral cats encounter traps, necessitating frequent bait replacement. We compared the effectiveness of baits and lures by analyzing capture rates of feral cats and non-targets and monitoring animal visits to bait stations with remotely-triggered cameras. We tested four different baits and attractants: canned cat food, sardines, catnip, and a bait sausage that we formulated from pork and fat. We trapped for a total of 3,389 trap nights and captured 35 feral cats. There were 323 incidences of trap interferences, reducing the effective trap nights (ETN) to 3,225. The primary cause of trap interference was feral pigs rolling over traps (n = 185, 57.3% of interferences). The primary non-target species captured were small Indian mongooses (n = 74, 22.9% of interferences). Overall, more cats and mongooses were captured using sardines, although the catch frequencies were not dependent on the bait type used. We obtained photographs of 1,476 small mammals at the bait stations. Mongooses were the principal mammals photographed (n = 939, 69.5% of pictures). We also obtained 398 photographs of rats (29.5%) and 9 (0.7%) of mice. Feral cats were photographed only 5 (0.4%) times. We found strong differences between mongooses, rodents, and cats photographed at the four bait types. Sardines were the most visited bait type (n = 641, 47.4% of photographs). Pork sausage and cat food accounted for 383 (28.3%) and 322 (23.8%) visits while catnip had only 67 (5.0%) 3 visits. Feral cats were photographed only at sardine bait. Mongooses were attracted primarily to sardines (49.3%). Pork sausage was the most attractive bait to rats, accounting for 44.5% of photographs. Due to the high rate of non-target interference, other attractants need to be tested for successful feral cat control programs. Population genetics can provide information about the demographics and dynamics of invasive species that is beneficial for developing effective control strategies. We studied the population genetics of feral cats on Hawai`i Island by microsatellite analysis to evaluate genetic diversity and population structure, assess gene flow and connectivity among three populations, identify potential source populations, characterize population dynamics, and evaluate sex-biased dispersal. High genetic diversity, low structure, and high number of migrants per generation supported high gene flow that was not limited spatially. Migration rates revealed that most migration occurred out of West Mauna Kea. Effective population size estimates indicated increasing cat populations despite control efforts. Despite high gene flow, relatedness estimates declined significantly with increased geographic distance and Bayesian assignment tests revealed the presence of three population clusters. Genetic structure and relatedness estimates indicated male-biased dispersal. Mauna Kea may be a source population that can be targeted for control. However, recolonization seems likely given the great dispersal ability that may not be inhibited by barriers such as lava flows. Genetic monitoring will be necessary to assess the effectiveness of future control efforts. Despite the long history of feral cats in Hawai`i, there has been little research to provide strategies to improve control programs and reduce depredation on endangered species. Our objective was to develop a predictive model to determine how landscape features on Mauna Kea such as habitat, elevation, and proximity to roads affect the number of feral cats captured at each trap. We used log-link generalized linear models and QAICc model ranking criteria to determine the effect of these factors. We found that the number of cats captured per trap was related to trapping effort, habitat type, and whether traps were located on the West or North Slope of Mauna Kea. We recommend an adaptive management strategy to minimize trapping interference by non-target small Indian mongoose (Herpestes auropunctatus) with toxicants, to focus trapping efforts in māmane (Sophora chrysophylla) habitat on the West slope of Mauna Kea, and to cluster traps near others that have previously captured multiple cats.
Passerine bird trends at Hakalau Forest National Wildlife Refuge, Hawai`i
(2009-01) Camp, Richard J. Pratt, Thane K. Jeffrey, John J. Woodsworth, Bethany
Hakalau Forest National Wildlife Refuge, on the Island of Hawai‘i, was established in 1985 to protect native forest birds, particularly endangered species. Management actions on the 15,400 ha refuge include removing feral ungulates from the forest and pastures, controlling invasive alien plants, reforesting pastures, and supplementing endangered plant populations. To assess effects of this habitat improvement for birds, we calculated annual density estimates from point transect surveys and examined population trends for eight native and four alien passerine bird species over the 21 years since the refuge was established (1987-2007). We examined trends using a Bayesian approach to log-linear regression. We tested for changes in bird density in three study areas: (1) a middle elevation forest that had been heavily grazed, (2) an upper elevation pasture that was reforested during the study, and (3) a lower area of relatively intact forest that was formerly lightly grazed. In the middle study area, we found that densities of Hawai‘i ‘Elepaio (Chasiempis s. sandwichensis), and the endangered ‘Akiapōlā‘au (Hemignathus munroi) and Hawai‘i Creeper (Oreomystis mana) increased, and that all other native birds showed stable trends and exhibited no evidence of declining trends as has been seen elsewhere in much of Hawai‘i. Trends for all alien birds were also stable, except that House Finch (Carpodacus mexicanus) density has declined. In the lower study area, Hawai‘i Creeper and Hawai‘i ‘Ākepa (Loxops c. coccineus) showed increasing trajectories, and densities have declined for the other native species. Within the reforested upper study area, densities increased for three common native species—Hawai‘i ‘Amakihi (Hemignathus virens), ‘I‘iwi (Vestiaria coccinea), and ‘Apapane (Himatione sanguinea)—and two alien species—Japanese White-eye (Zosterops japonicus) and House Finch. Bird trends at the Hakalau refuge provide some of the first results of habitat improvement for forest birds in Hawai‘i. Restoring tree cover in open pasture and assisting recovery of high-quality habitat benefits both endangered and abundant native birds.
Population trends of native Hawaiian forest birds, 1976-2008: the data and statistical analysis.
(2009-11) Camp, Richard J.; Gorresen, P. Marcos; Pratt, Thane K.; Woodworth, Bethany L.
The Hawaii Forest Bird Interagency Database Project has produced a centralized database of forest bird survey data collected in Hawai`i since the mid-1970s. The database contains over 1.1 million bird observation records of 90 species from almost 600 surveys on the main Hawaiian Islands—a dataset including nearly all surveys from that period. The primary objective has been to determine the status and trends of native Hawaiian forest birds derived from this comprehensive dataset. We generated species-specific density estimates from each survey and tested for changes in population densities over the longest possible temporal period. Although this cumulative data set seems enormous and represents the best available information on status of Hawaiian forest birds, detecting meaningful population distribution, density, and trends for forest birds in Hawai`i has been difficult. These population parameters are best derived from long-term, large-scale, standardized monitoring programs. The basis for long-term population monitoring in Hawai`i was established by the Hawaii Forest Bird Survey of 1976-1983 (Scott et al. 1986). Since then, however, only key areas have been resurveyed, primarily to monitor rare species. The majority of surveys since the early 1980s have been conducted by numerous, independent programs, resulting in some inconsistencies in methodology and sampling that in some cases has been intermittent and usually at limited scale (temporally or spatially). Thus, despite the consolidation of data into a centralized database, our understanding of population patterns is rather limited, especially at the regional and landscape scales. To rectify their deficiency, we present a framework to improve the understanding of forest bird trends in Hawai`i through an overarching monitoring design that allocates sampling at appropriate regional and temporal scales. Despite the limitations of the current monitoring effort, important generalities stand out vividly from the multiplicity of species-specific trends. Overall, in marginal habitats the Hawaiian passerine fauna continues to decline, with populations of most species shrinking in size and distribution. Since the early 1980s, 10 species that were rare at the time may now be extinct, although one, the `Alalā (Corvus hawaiiensis), survives in captivity. Dedicated search effort for the remaining nine species has been inadequate. Of the 22 species remaining, eight have declined, five appear to be stable, two are increasing, and the trend for seven species is unclear. On the bright side, native passerines, including endangered species, appear to be stable or increasing in areas with large tracts of native forest above 1,500 m elevation, even while decreasing in more fragmented or disturbed habitats, particularly at lower elevation. For example, all eight native species resident at Hakalau Forest National Wildlife Refuge have shown stable trends or significant increases in density over the long-term. Thus, native birds are ever more restricted to high-elevation forest and woodland refugia. It is these upland habitats that require sustained and all-out restoration to prevent further extinctions of Hawaiian forest birds.
Assessment of fuels, potential fire behavior, and management options in subalpine vegetation on Mauna Kea Volcano, Hawai`i
(2009-11) Thaxton, Jarrod M.; Jacobi, James D.
Fire is a major threat to habitat for the endangered Palila (Loxioides bailleui) within subalpine vegetation on Mauna Kea volcano, Hawai‘i. The presence of large amounts of fine fuel from grasses, dry climate, and human ignition sources produces a significant risk of wildfire in this area year-round. The purpose of this report is to provide information on fuels and potential fire behavior that will contribute to fire management of Palila habitat. Recommended actions will contribute to the conservation of these native forests and facilitate restoration in degraded areas. To assess the effects of grass invasion on fuel conditions and potential fire danger, we quantified vegetation and fuels across an elevation gradient from grasslands into sub-alpine forests on the west slope of Mauna Kea. Our results indicated that grass cover was reduced under tree canopy in plots below ~2,500 m elevation, but at higher elevations grass cover was higher under trees than in the open. However, tree canopy cover below 2,500 m elevation was not high enough overall (~25% on average) to result in significant reductions in fine fuels at the landscape level. Sampling directly under and away from tree crowns at multiple elevations suggested that below ~2,500 m, the presence of tree canopy cover can reduce grass fuels significantly. Furthermore, moisture content of live surface fuels was increased under tree canopy compared with open areas. These results suggest that restoration of forest cover may have the potential to alter grass fuels in ways that decrease the threat of fire in some subalpine forests. Fire behavior estimates based on fuel data from grasslands, mixed forest and māmane forest indicated the need for fuelbreaks of at least 20-30 m to limit fire spread in most areas. In many cases, breaks as wide as 40 m are required to limit fire spread risk under extreme weather conditions. Based on our fuels data and fire behavior predictions, recommended actions include: (1) construction of new or expansion of existing fuelbreaks to immediately reduce fire risk to the most sensitive areas adjacent to the core Palila population on the southwest slope and the translocated Palila population on the north slope of Mauna Kea, (2) enhancement of forest restoration activities to increase fuel moisture and reduce grass fuel loads (3) installation of water sources (diptanks) in both areas to decrease firefighter response time, and (4) increased public education and awareness with regard to fire danger on Mauna Kea.
Native coastal flora and plant communities in Hawai`i: their composition, distribution, and status.
(2009-12) Warshauer, Fredrick R.; Jacobi, James D.; Price, Jonathan P.
The Hawaiian coastal flora primarily includes the halophytic (salt-adapted) plants closest to the area of salt spray and wave wash, often concentrated within a distinct strand zone, and usually growing as low mats. However, behind the strand is a zone of vegetation that is quite varied in composition and structure, but somewhat less specialized in life form, which is also adapted to the specific conditions of the coastal environments and to those at different locales. Coastal plant communities in Hawai‘i are distributed across a very wide range of conditions, and are anything but homogeneous. Primary factors that influence their composition and structure include moisture, substrate, and exposure to wind and salt water. Some of these factors also have roles in dispersal, competition, trauma, and periodic reordering of local community compositions. External to these are anthropogenic impacts which may have a similar scale of influences today. Between 2000 and 2005 we surveyed a total of 133 coastal sites on the islands of Moloka‘i, Maui, and O‘ahu. On O‘ahu we visited 28 sites, 50 sites were surveyed on Moloka‘i, 36 sites on West Maui, and 19 sites on East Maui. The survey areas were selected primarily to sample a region’s community variety and composition, and were distributed within the diversity of moisture zones found in the coastal regions of each island. A few sites were visited on Kaua‘i and Hawai‘i, but these islands are in need of much more survey work and thus have limited commentary in the current summary. The smaller main islands (Ni‘ihau, Lāna‘i, and Kaho‘olawe), as well as many of the small offshore islets, were not visited at all in this assessment. During this project we recorded 142 taxa of native plants out of 169 that were expected based on past plant collections and from the literature. A total of 105 coastal plants were recorded on Moloka‘i, 85 on Maui, and 52 on O‘ahu. Thirty-eight species were found on all three of the islands we surveyed, 53 on at least two islands, and 51 plants were found on only one of these islands. We encountered 12 listed endangered taxa, 2 threatened taxa, and 13 species of concern (SOC) but with no official listing status, as well as many other taxa that are now relatively uncommon within the Hawaiian coastal zone. The number of plants per site varied considerably between the areas surveyed, but the greatest diversity was found on Moloka‘i and Maui, with their richest sites containing 30 and 32 species, respectively. On Maui 22 (40%) of the sites had less than10 native coastal plant species, 30 (55%) had 10 – 20 species, and 3 (5%) with more than 20 species. A different situation was found on Moloka‘i where only 10 (20%) of the sites had less than 10 native coastal plant species, 28 (56%) had 10 – 20 species, and 12 (24%) with more than 20 species. On O‘ahu seven (25%) sites had less than 10 native plant species, 20 (71%) had 10 – 20 species, and only one site (Ka‘ena Point) had over 20 species, but, in this case just a total of 21 coastal plant species. The current coastal flora of O‘ahu was somewhat reduced compared to the other two islands, likely a result of the much greater human-related impacts on the coastal zone of O‘ahu. Additionally, the remaining coastal vegetation on O‘ahu is nearly all within the dry zone. The most influential site factor for Hawaiian coastal communities is the range of moisture that occurs across any particular area. The greater the moisture zone range, the more species are likely to be found in a region. The composition of strand communities varies considerably spatially, but in most given locations communitiescontain limited subsets of the species richness potentially available. The coastal vegetation is characterized by low growing and mat forming species in areas closest to the ocean and by taller plants farther inland or where available soil has accumulated locally. In the arid and dry zones, a few annual species, mostly grasses, are seen; the viii rest of native coastal flora is perennial. Exposure to salt water and onshore flow of salt mist (‘ehukai) comprise the harshest ecological factors within the coastal zone. Exposure to ‘ehukai, strong winds, and brackish basal ground water all influence this generalization and add variegation to an area’s vegetation structure and composition. A range in other site conditions helps to further diversify the structural and species composition of the communities. Understanding of these conditions can assist managers with identification of areas to preserve and manage, and help to guide restoration attempts. Alien plants represent one of the greatest threats to native coastal vegetation in that any one of several invasive species can completely displace or prevent the colonization of entire suites of native species. Alien animals are another important threat, one that frequently opens the door for, or tips the balance to, alien plants. The most obvious and widespread animal species are pastured and free-roaming ungulates, particularly cattle, goats, sheep, pigs, and deer. The numbers and distributions of some ungulate species may have surged and waned variably over time and space, but their impacts are unequivocally negative in the coastal zone in any abundance. Human development and use of coastal areas continues to exert severe, usually permanent, impacts to remaining native coastal vegetation. Recreational activities, in particular, tend to be a widespread detriment to coastal plant communities. The fragmentation of habitats and compounding affects of an associated array of disturbances resulting from urban and agricultural activities have led to considerable attrition of species from predominately native dominates areas in the coastal zone. These losses are continuing, perhaps accelerating, with the expanding use of the limited coastal areas throughout the islands for resort, residential, and recreational activities. Given the cumulative stresses that Hawai‘i’s coastal communities have experienced in recent years, the few plant extinctions that have occurred in that habitat indicates there is still time to employ effective management to prevent more loss of diversity. However, the widespread damage to coastal vegetation and the rarity of so many species indicates the urgency for supplying sufficient targeted management to preserve species and to restore community composition, structure, and function. The coastal vegetation’s adaptation to natural disturbance, as evident from the harsh environment it occupies, coupled with its regenerative capability, may have helped these communities survive thus far. This suggests a good potential for preservation of the biota of these regions if effective and strategic management actions are effected soon. A conservation strategy that incorporates both protected regions and species augmentation may be able to reverse declining trends in Hawaiian coastal communities if applied in time and at sufficient scale. Protection of coastal regions should feature reduction or elimination of the major stress factors that accompany alien plants and ungulates, as well as reducing and compensating for the adverse consequences of land use. A number of sites on each island stand out with high species diversity and/or populations of rare plant species, as well as still having an established connection with contiguous lowland vegetation. These sites can serve as core areas for a regional approach to managing strips of coastal communities and their associated lowland vegetation. The following conclusions and potential management strategies have been derived from our survey observations:  A regional approach to coastal resource conservation is likely to be the most effective approach to secure an island’s native coastal vegetation.  It is important to identify and prioritize coastal vegetation areas that still retain connections to native lowland plant communities. Even depleted communities can still contribute to the coastal areas’ biodiversity, and both could be stabilized ix and augmented where warranted. Managing both coastal and lowland areas together can be an efficient strategy for conserving a variety of resources and processes across modestly-sized areas.  Removal or significant reductions of feral ungulates is one of the most pressing management needs along certain stretches of the coastlines of the main Hawaiian Islands. Strategic fencing can be an effective tool for excluding ungulates and potentially predators. However, high installation and maintenance costs limit their use presently, particularly near shorelines. Development of cost effective corrosion-resistant materials and appropriate designs could encourageincreased use of fences in coastal areas.  Given the ongoing spread of numerous alien plants into new regions, immediate removal of the early colonizing individuals of particularly threatening species from native coastal vegetation can proactively prevent an increase in ecosystem disruption.  Expand public education and outreach programs to enlist more support of coastal community conservation from the public. These surveys have provided more and current information on the ecology, composition, distribution, and status of coastal plant communities and species in selected portions of the main Hawaiian Islands. Although not as rich in endemic species as are upland communities, the Hawaiian coastal flora is relatively diverse, and taken as a whole, is still quite intact with very few historically known species that are now extinct. Although the coastal zone has been heavily impacted over the past 250 years, many high quality examples of diverse plant communities can still be found, particularly in the wet and mesic habitats on the islands of Maui and Moloka‘i. Management efforts that are regionally focused on reducing the impacts of invasive species (both plants and animals) and maintaining the connection between the coastal strand and lowland vegetation, coupled with expanding public awareness of the value of coastal communities, can allow for effective restoration and maintenance of this unique set of ecosystems for the future.
Status and trends of native birds in the Keauhou and Kilauea Forest, Hawai`i Island.
(2010-05) Camp, Richard J.; Jacobi, James D.; Pratt, Thane K.; Gorresen, P. Marcos; Rubenstein, Tanya
A Safe Harbor Agreement (SHA) is a voluntary arrangement between the U.S. Fish and Wildlife Service and non-Federal landowners to promote the protection, conservation, and recovery of listed species without imposing further land use restrictions on the landowners. Kamehameha Schools is considering entering into a SHA for their Keauhou and Kīlauea Forest lands on the island of Hawai′i. Bird surveys were conducted in 2008 to determine the current occurrence and density of listed species for the Keauhou and Kīlauea Forest, a prerequisite for establishing an agreement. Because of different management practices in the proposed SHA area we stratified the survey data into intact and altered forest strata. The listed passerines—′Akiapōlā′au (Hemignathus munroi), Hawai′i Creeper (Oreomystis mana), and Hawai′i ′Ākepa (Loxops coccineus)—occur in both strata but at low densities. The endangered ′Io (Hawaiian Hawk; Buteo solitarius) also occurs within both strata at low densities. This report was prepared for the U.S. Fish and Wildlife Service and Kamehameha Schools to provide information they can use to establish baseline levels for the SHA. In addition, we describe the status and trends of the non-listed native birds.
Limiting factors of five rare plant species in mesic forests, Hawai`i Volcanoes National Park
(2010-05) Pratt, Linda W.; VanDeMark, Joshua R.; Euaparadorn, Melody
Five rare or endangered plant species native to Kīpuka Puaulu and Kīpuka Kī were studied for two years to determine their stand structure, patterns of reproductive phenology, success of fruit production, potential pollinators, greenhouse seed germination rates, presence of soil seed banks, impacts of seed-predating rats, seed predation by insects, seedling predation by Kalij pheasant (Lophura leucomelanos), and seedling survival with different treatments. Species monitored were the trees Hibiscadelphus giffardianus (hau kuahiwi), Melicope hawaiensis (manena), M. zahlbruckneri (alani), and Zanthoxylum dipetalum var. dipetalum (kāwa`u), and the vine Sicyos macrophyllus (`ānunu). Limiting factors identified for H. giffardianus were rat predation of seeds, bark-stripping, low fruit production likely resulting from the inter-relatedness of the planted population, and loss of original pollinators. For M. hawaiensis, rat and native insect predation of seeds limited the number of seeds available, and natural seedling recruitment was very low. Pollination was effected by an alien insect species. For M. zahlbruckneri, native insect predation and rat depredation greatly reduced the number of seeds available for germination. The low proportion of flowers that became fruit indicated a lack of successful pollination or self-incompatibility. For S. macrophyllus, rat predation of seeds on the ground and in the seed bank reduced the number of seeds available for natural regeneration. Alien grasses were suspected to limit seedling recruitment. Most floral visitors were alien insect species. Seedling recruitment appeared to be the most vulnerable life stage for Z. dipetalum var. dipetalum. Both alien Kalij pheasants and unknown insect species were implicated as seedling predators/herbivores.
Changes in prevalence of avian malaria on the Alaka`i Plateau, Kaua`i, 1997-2007.
(2010-06) Atkinson, Carter T.; Utzurrum, Ruth B.
We determined prevalence of malarial infections in samples of native and non-native forest birds that were sampled at three locations on the Alaka`i Plateau between 1994-1997 and again between 2007-2009. The three sites spanned the elevational range of the plateau and were located at Kawaikōī Stream (1100 m), the upper drainage of Mōhihi Stream (1250 m) and the vicinity of Halepa`akai Stream near Sincock’s Bog (1350 m). We detected a dramatic and significant increase in prevalence of avian malaria both at the lower (Kawaikōī) and upper (Halepa`akai) ends of the Alaka`i Plateau during the past decade. Overall prevalence of infection increased threefold from 11% to 30% at Kawaikōī Stream and tenfold from 2% to 20% at Halepa`akai Stream. Much of this increase is likely a result of local transmission, since two sedentary native species, `Elepaio and Kaua`i `Amakihi, have experienced some of the largest increases in prevalence. Curiously, prevalence has not changed significantly at Mōhihi Stream and remains at approximately 10%. We also detected avian trypanosomes (Trypanosoma sp.) in both recent and historic blood samples from Nutmeg Mannikins (Lonchura punctulata) that were captured on the plateau. This is the first report of this mosquito-transmitted blood protozoan from the Hawaiian Islands and evidence indicates that it has been a previously undetected blood parasite in the islands for at least 15 years and likely longer. We found no evidence to indicate that the parasite has spread to native Hawaiian forest birds, but our sample sizes are limited. While our study was not designed to detect the specific factors responsible for the changes in prevalence of malaria at lower and upper portions of the plateau, the results are consistent with predicted increases in prevalence that might be expected in a warming climate and clearly show that environmental conditions necessary to support transmission of malaria now exist throughout major portions of the Alaka`i Plateau. Additional field work to identify larval habitat for mosquitoes, adult mosquito distribution and density, and the relative role of human activity, feral ungulates, and interactions between changing climatic conditions and the deeply dissected topography of the plateau may help to identify why some areas have experienced significant increases in malarial prevalence.
Limiting factors of four rare plant species in Ola`a forest of Hawai`i Volcanoes National Park.
(2010-07) VanDeMark, Joshua R.; Pratt, Linda W.; Euaparadorn, Melody
Three endangered or candidate endangered plant species native to `Ōla`a Forest (Cyrtandra giffardii, ha`iwale; Phyllostegia floribunda, a mint with no common name; and Sicyos alba, `ānunu) were studied for more than two years to determine their stand structures, short-term mortality rates, patterns of reproductive phenology, success of fruit production, seed germination rates in the greenhouse, presence of soil seed bank, and survival of both natural and planted seedlings. The role of rodents as seed predators was evaluated for S. alba using seed offerings in open and closed stations. A fourth endangered species (Cyrtandra tintinnabula) at a remote site in `Ōla`a was visited to determine its stand structure and mortality rate. Cyrtandra giffardii displayed a stable population structure with many adults and few small or very large plants; the monitored population had a mortality rate of 7.3% over three years. Mortality of plantings from 2003-2004 in a re-introduced population of Phyllostegia floribunda was 21.4%. The stand structure of C. tintinnabula indicated a relatively stable population with both small and large plants present and a short-term mortality rate between visits of 14.5-17.0%. Four groups of S. alba vines were monitored; 3 of these have persisted in place for at least 15 years. All species monitored had annual patterns of flower and fruit phenology, although male inflorescences of S. alba showed a subannual pattern. Successful transition of flowers to fruit was high for P. floribunda (51.5%), moderate for C. giffardii (23.3%), and undetermined for S. alba. High percentage viability was demonstrated for seeds of P. floribunda and S. alba (78.5-100% positive to strongly positive in tetrazolium tests), but seed viability was not tested for C. giffardii. Greenhouse germination rates were high for P. floribunda (88.0-92.0%), but variable and relatively low for C. giffardii (0-19.3%) and S. alba (4.0-11.1% in 2007 and 0 in 2008). No soil seed bank was detected for S. alba in 3 seasonal samplings, but P. floribunda was found to have a viable seed bank in April that persisted from at least the previous summer. Rodent predation of S. alba seeds was 93.3% in fruit offerings in accessible bait stations. Mortality of natural seedlings was high for both P. floribunda (90.2%) and S. alba (69.7%). Planted seedlings of P. floribunda produced flowers and fruit in their first year, and reproduction was higher in sunny plots than in shady plots. Mortality was high in both planting treatments, and 2 survival rates did not differ significantly in sun and shade (χ 2 = 0.48, df = 1, p = 0.490). Three planted seedlings of S. alba survived for 12-16 months but did not reproduce. Floral visitors were observed at C. giffardii and P. floribunda using digital video cameras and recorders. In almost 200 hours of observation, no visitors entered the flowers of C. giffardii, although one very small insect, either a micro-wasp (Hymenoptera) or fly (Diptera) was seen on the exterior of a corolla. In almost 300 hours of video observation, three floral visitors were identified at P. floribunda flowers. Honeybees (Apis mellifera) were likely pollinators, as they contacted both anthers and stigma of flowers. The mean visitation rate of honeybees was 0.003 visit/flower/hour, and visit duration ranged from 2 to 17 seconds. Fruitflies (Drosophilidae of undetermined species) crawled around flower interiors, but did not seem to forage for either nectar or pollen. Fruit fly mean visitation rate was 0.006 visit/flower/hour, and visit duration was 28 to 1,424 seconds. The third observed insect visitor was an endemic geometrid moth caterpillar (Lophoplusia giffardi), which was seen feeding on foliage and flowers of P. floribunda. In conclusion, two of the three regularly-monitored rare plant species of `Ōla`a Forest appeared to have more than one limiting factor inhibiting the natural increase in their populations, while for P. floribunda the most important factor was high seedling mortality. Most plants of the monitored C. giffardii population appeared to be hybrids, probably with the more common species C. lysiosepala. Seed germination rates were low, and natural seedlings were not observed. Pollinators were not seen in many hours of observation, indicating that cross pollination is a rare or uncommon event. The re-introduced population of P. floribunda had relatively low mortality, and reproduction was successful with high rates of fruit formation from abundant flowers. Seed germination rates were high, and a soil seed bank was detected. Natural seedling recruitment was observed, but high seedling mortality indicated that this life stage was the most vulnerable in the species. The population of S. alba was small and the vine life form precluded an accurate estimate of the number of adult plants in `Ōla`a Forest. Natural dormancy was likely a factor in the observed low rate of seed germination. No soil seed bank was detected, and alien rodents were implicated as seed predators. Natural recruitment was observed at multiple sites in `Ōla`a, but seedling mortality was high. The cause of seedling mortality was not identified.
Efficacy of a commercial cararypox vaccine for protecting Hawai`i `Amakihi from field isolates of avipoxvirus.
(2010-09) Atkinson, Carter T.; Wiegand, Kimberly C.; Triglia, Dennis A.; Jarvi, Susan I.
At least three variants of avian pox virus are present in Hawai’i - Fowlpox from domestic poultry and a group of genetically distinct viruses that cluster within two clades (Pox Variant 1 and Pox Variant 2) that are most similar to Canarypox based on DNA sequence of the virus 4b core protein gene. We tested whether Hawai’i ‘Amakihi can be protected from wild virus isolates with an attenuated live Canarypox vaccine that is closely related to isolates that cluster within clade 1 (Pox Variant 1) based on sequence of the attenuated Canarypox virus 4b core protein. Thirty-one (31) Hawai`i ‘Amakihi (Hemignathus virens) with no prior physical evidence of pox infection were collected on Mauna Kea from xeric, high elevation habitats with low pox prevalence and randomly divided into two groups. One group of 16 was vaccinated with Poximmune C® while the other group received a sham vaccination with virus diluent. Four of 15 (27%) vaccinated birds developed potentially life-threatening disseminated lesions or lesions of unusually long duration, while one bird never developed a vaccine-associated lesion or “take”. After vaccine-associated lesions healed, vaccinated birds were randomly divided into three groups of five and challenged with either a wild isolate of Fowlpox, a Hawai`i `Amakihi isolate of a Canarypox-like virus from clade 1 (Pox Variant 1) or a Hawai`i `Amakihi isolate of a Canarypox-like virus from clade 2 (Pox Variant 2). Similarly, three random groups of five unvaccinated ‘Amakihi were challenged with the same virus isolates. Vaccinated and unvaccinated ‘Amakihi challenged with Fowlpox had transient infections with no clinical signs of infection. Mortality in vaccinated ‘Amakihi that were challenged with Pox Variant 1 and Pox Variant 2 ranged from 0% (0/5) for Pox Variant 1 to 60% (3/5) for Pox Variant 2. Mortality in unvaccinated ‘Amakihi ranged from 40% (2/5) for Pox Variant 1 to 100% (5/5) for Pox Variant 2. While the vaccine provided some protection against Pox Variant 1, serious side effects and low efficacy against Pox Variant 2 make it risky to use in captive or wild honeycreepers.
Baseline survey for rare plant species and native plant communities within the Kamehameha schools' Lupea Safe Harbor Planning Project Area, North Kona District, Island of Hawai`i.
(2010-12) Jacobi, James D.; Warshauer, Frederick R.; Price, Jonathan P.
Kamehameha Schools, in conjunction with several federal, state, and private organizations, has proposed to conduct conservation management on approximately 5,340 ha (~13,200 acres) of land they own in the vicinity of Kīpukalupea in the North Kona District on the island of Hawai`i. The goal of this program is to restore and enhance the habitat to benefit native plant and animal populations that are currently, or were formerly, found in this site. The initial phase of this project has been focused on various activities including conducting baseline surveys for bird and plant species so Kamehameha Schools could develop a Safe Harbor Agreement (SHA) for the proposed project lands relative to the habitat management and species reintroduction efforts they would like to conduct in the Lupea Project area. This report summarizes methods that were used to collect field data on plant species and communities within the project area, and the results of that initial survey. The information was used to calculate baseline values for all listed threatened or endangered plant species found, or expected to be found, within the project area, and to design a monitoring program to assess changes in plant communities and rare plant species relative to management activities over the duration of the SHA. The Lupea Project area contains excellent examples of several high elevation native plant communities including montane dry forest and woodland, native subalpine shrubland, and native grassland. Between November 2003 and January 2004 we sampled plant communities and species along seven transects established through the project area. A total of 109 plant species were found during this survey, within the transect grid and in nearby areas. Forty-four of these plants are endemic species, 21 are indigenous species, 43 are introduced, and one species is believed to have been introduced to Hawai`i by early Polynesian settlers. Only one federally listed Endangered plant, Asplenium peruvianum var. insulare, was found within the survey area. Additionally, we found one immature plant that may be Sicyos macrophyllus, a candidate species for listing.However, we were not able to make a definite determination of this species‟ identity since it did not have fruits or flowers. Finally, we documented four plant species within the survey area that have no official status designation but are considered to be rare and informally recognized as “species of concern” (SOC) as they appear to be declining in distribution and abundance statewide. These included Chamaesyce olowaluana, viii Eragrostis deflexa, Sisyrinchium acre, and Tetramolopium consanguineum. In addition to conducting field surveys, we performed a query on a spatial database developed by Dr. Jonathan Price of the University of Hawai`i at Hilo which models the potential range of all native Hawaiian plant species based on historic observations and a set of environmental parameters. The potential species list for the Lupea Project area includes 47 taxa that we did not find during our surveys, as well as three other listed species that were not modeled by Price, but known from historic records in adjacent habitats. Some of these species are extremely rare or, in some cases have been locally extirpated. However, most of the plants that were predicted but not found during our surveys are expected to be located with additional searching, or may potentially recolonize the area following the elimination of ungulates and initiation of other restoration efforts. Forty-four introduced plant species were found within the survey area, seven of which are considered to be highly invasive. These include the grasses Pennisetum clandestinum and Pennisetum setaceum, vines Delairea odorata and Passiflora tarminiana, herbs Senecio madagascariensis and Verbascum thapsus, and the shrub Rubus niveus. Non-zero baseline values are proposed for the one listed plant species found within the Lupea Project area, one species that is a candidate for listing, and the four other rare species we found that may be considered for listing in the future. Additionally, a zero baseline is proposed for 23 other species that were predicted, but not found within the project area. These include 14 Endangered species, one Threatened species, two candidates for listing, and six species of concern. Subsequent monitoring of the site will be necessary to determine if the populations of these species have increased or decreased relative to their baseline values. It is presumed that the management activities Kamehameha Schools has proposed for this area, particularly removal of the ungulates and weed control, will provide a benefit to the habitat as a whole and allow for natural regeneration and maintenance of the all elements of the plant communities found there.

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