Haleakala Research Articles

Early Uses by Ancient Hawaiians, and Environmental, Geographical, and Ecological History, of Haleakalā Crater, East Maui

This research assesses the environmental uses of Haleakalā Crater, and adjoining east Maui areas, by native Hawaiians during recent centuries, and evaluates the modern utilization of this volcanic depression. The study methods examine, and focus on, numerous historical and modern accounts and reports. Three historical periods were identified as follows: (1). A phase, from the ~1400s until contact with foreigners in 1778, characterized by the development of settlements, population expansion, the intensification of traditional agriculture, and the political consolidation of Maui. The construction of the Kiha-a-Pi‘i-lani trail across the crater enhanced travel between distant island areas. (2). Following the collapse of Maui’s human populations during the late 1700s, and until the 20th century, came a period distinguished by scientific exploration of the crater, and intentional or accidental introductions of animals, including goats, horses, cattle, and wild dogs. (3). After Haleakalā became a National Park in 1916, efforts to eradicate introduced animals and to encourage the reproduction of silverswords and other plants were initiated. Unfortunately, in retrospect, construction of a modern paved road, improvement of hiking trails, and building of facilities allowed swift access to the Park and substantially increased tourist numbers, up to ~2 million yearly visitors. Faced with such crowds, the long-term planning of Park resources appears to be a formidable task.

Household Labor Practices and Dryland Agroforestry in Upland Kula, Maui Island

ABSTRACT The relationship between agricultural systems and the development of complex societies in ancient Hawai`i has been debated for decades. To contribute to this debate, we examine a terrace complex representing an extended family agricultural land plot in the Kula dryland field system of East Maui, Hawaiian Islands. Botanical, faunal, soil, and architectural analysis data reveal a variety of household labor practices related to agroforestry ca. a.d. 1400–1820. A pre-human open forest soil substrate was replaced with stone agricultural terracing which was in turn enclosed by upslope-downslope garden walls that parceled the terrace complex into distinct garden areas. These results lead us to conclude that a wide range of specialized upland activities were practiced, including food cultivation, forestry, pig husbandry, and bird-hunting. The net sum of these local activities helped underpin the formative process of larger regional-level agricultural systems which in turn can inform us about polity-level staple and wealth finance systems.

High resolution lidar data shed light on inter-island translocation of endangered bird species in the Hawaiian Islands.

Translocation, often a management solution reserved for at-risk species, is a highly time-sensitive intervention in the face of a rapidly changing climate. The definition of abiotic and biotic habitat requirements is essential to the selection of appropriate release sites in novel environments. However, field-based approaches to gathering this information are often too time intensive, especially in areas of complex topography where common, coarse-scale climate models lack essential details. We apply a fine-scale remote sensing-based approach to study the 'akikiki (Oreomystis bairdi) and 'akeke'e (Loxops caeruleirostris), Hawaiian honeycreepers endemic to Kaua'i that are experiencing large-scale population declines due to warming-induced spread of invasive disease. We use habitat suitability modeling based on fine-scale light detection and ranging (lidar)-derived habitat structure metrics to refine coarse climate ranges for these species in candidate translocation areas on Maui. We found that canopy density was consistently the most important variable in defining habitat suitability for the two Kaua'i species. Our models also corroborated known habitat preferences and behavioral information for these species that are essential for informing translocation. We estimated a nesting habitat that will persist under future climate conditions on east Maui of 23.43 km2 for 'akikiki, compared to the current Kaua'i range of 13.09 km2 . In contrast, the novel nesting range for 'akeke'e in east Maui was smaller than its current range on Kaua'i (26.29 vs. 38.48 km2 , respectively). We were also able to assess detailed novel competitive interactions at a fine scale using models of three endemic Maui species of conservation concern: 'ākohekohe (Palmeria dolei), Maui 'alauahio (Paroreomyza montana), and kiwikiu (Pseudonestor xanthophrys). Weighted overlap areas between the species from both islands were moderate (<12 km2 ), and correlations between Maui and Kaua'i bird habitat were generally low, indicating limited potential for competition. Results indicate that translocation to east Maui could be a viable option for 'akikiki but would be more uncertain for 'akeke'e. Our novel multifaceted approach allows for the timely analysis of both climate and vegetation structure at informative scales for the effective selection of appropriate translocation sites for at-risk species.

Ecological network structure in response to community assembly processes over evolutionary time.

The dynamic structure of ecological communities results from interactions among taxa that change with shifts in species composition in space and time. However, our ability to study the interplay of ecological and evolutionary processes on community assembly remains relatively unexplored due to the difficulty of measuring community structure over long temporal scales. Here, we made use of a geological chronosequence across the Hawaiian Islands, representing 50 years to 4.15million years of ecosystem development, to sample 11 communities of arthropods and their associated plant taxa using semiquantitative DNA metabarcoding. We then examined how ecological communities changed with community age by calculating quantitative network statistics for bipartite networks of arthropod-plant associations. The average number of interactions per species (linkage density), ratio of plant to arthropod species (vulnerability) and uniformity of energy flow (interaction evenness) increased significantly in concert with community age. The index of specialization has a curvilinear relationship with community age. Our analyses suggest that younger communities are characterized by fewer but stronger interactions, while biotic associations become more even and diverse as communities mature. These shifts in structure became especially prominent on East Maui (~0.5million years old) and older volcanos, after enough time had elapsed for adaptation and specialization to act on populations in situ. Such natural progression of specialization during community assembly is probably impeded by the rapid infiltration of non-native species, with special risk to younger or more recently disturbed communities that are composed of fewer specialized relationships.

Predicted distribution of ‘ua‘u (Hawaiian petrel Pterodroma sandwichensis) nest sites on Haleakalā, Maui

Haleakalā National Park and montane areas on east Maui, Hawaiian Archipelago, support critical nesting habitat for endangered ‘ua‘u Hawaiian petrel Pterodroma sandwichensis. Habitat loss, non-native predators, and damage by feral ungulates are limiting factors for ground-nesting petrels at Haleakalā and throughout Hawai‘i. Because nesting habitats differ among the Hawaiian Islands, habitat distribution modeling for Hawaiian petrel has been island specific. Based on 2453 known nest site locations, we provide the first landscape-scale predictive model describing relative abundance and habitat available for nesting petrels throughout upper Haleakalā (1830 to 3055 m). We evaluated (principal components analyses and Pearson’s correlation) 13 spatial landscape and climate predictor variables associated with nest sites and the background landscape followed by random forest modeling to predict nest site density. Six variables (elevation, slope, topographic position index at 2 scales, heat load index, presence-absence ash/cinder, and presence-absence vegetation) indicated nest sites occurred non-randomly throughout the central part of the summit and crater; greatest concentrations were predicted along the crater rim and a ridgeline extending southwest from the summit. Moderately high predicted density occurred in the northeastern and northern crater. Lower elevations to the north, west, and south flanks of Haleakalā had relatively fewer predicted nest sites. Although we focused on higher elevations on Haleakalā, there is no reason to suspect that conservation efforts would not be successful at lower elevations, provided nesting petrels were protected from invasive predators, grazing ungulates, and significant land alteration.

Population response to connectivity restoration of high elevation tropical stream reaches in Hawai'i

AbstractTropical island streams are heavily impacted by water withdrawals to the detriment of native ecosystems. Freshwater fauna in the tropics often exhibit diadromous life‐history strategies, requiring hydrologic connectivity between upstream and nearshore habitats. During some or most of the year, this connectivity is generally lost at points of water withdrawal, typically constructed as a low‐head dam diversion. In 2010, instream flow standards (i.e., minimum environmental flows) were established for streams in East Maui, Hawai'i, which led to the partial restoration of flow in certain streams. In 2016, flow in several of these streams was then fully restored. We surveyed 10 streams before (2012) and after (2017) varying degrees of flow restoration (none, partial, full) to explore the short‐term consequences of reestablishing natural streamflow for the migratory fauna of high‐elevation tropical streams. Using visual point‐quadrat surveys, we quantified density and habitat usage of the endemic atyid shrimp (Atyoida bisulcata) and sampled A. bisulcata populations using seine‐netting to assess size frequency, sex ratio, percent ovigerous (egg bearing) females, and percent juveniles. In streams with full flow restoration, shrimp density increased in 2017 compared to 2012, while mean body size declined, suggesting increased recruitment following restoration. By contrast, streams that did not experience any flow restoration had similar shrimp densities and body sizes across years. Further, the male: female ratio declined from 18:1 in 2012 to 6.5:1 in 2017, suggesting an increase in reproductive potential of the population. Our results demonstrate that freshwater ecosystems upstream of diversion structures may respond rapidly to the restoration of hydrologic connectivity via increased recruitment of amphidromous species.

Characterizing mauka-to-makai connections for aquatic ecosystem conservation on Maui, Hawaiʻi

Mauka-to-makai (mountain to sea in the Hawaiian language) hydrologic connectivity – commonly referred to as ridge-to-reef – directly affects biogeochemical processes and socioecological functions across terrestrial, freshwater, and marine systems. The supply of freshwater to estuarine and nearshore environments in a ridge-to-reef system supports the food, water, and habitats utilized by marine fauna. In addition, the ecosystem services derived from this land-to-sea connectivity support social and cultural practices (hereafter referred to as socio-cultural) including fishing, aquaculture, wetland agriculture, religious ceremonies, and recreational activities. To effectively guide island resource management, a better understanding of the linkages from ridge-to-reef across natural and social usages is critical, particularly in the context of climate change, with anticipated increasing temperature and shifting precipitation patterns. The objective of this study was to identify spatial linkages that promote multiple and diverse uses, following the ridge-to-reef concept, at an island-wide scale to identify regions of high conservation importance for aquatic resources. We selected the Island of Maui as a study representative of many Pacific islands. Diverse datasets, including agricultural lands within watersheds, wetland locations, presence of stream species, indicators of freshwater input from streams, coral cover, nearshore fish biomass, socio-cultural data such as fishpond locations, wetland taro cultivation, beach recreation use, and lastly the dynamically downscaled Coupled Model Intercomparison Project Phase (CMIP5) future climate projections scenarios (Representative Concentration Pathway (RCP) 4.5 & 8.5) were used to examine the spatial linkages through hydrological connectivity from land to the sea. Zonation spatial planning software was used to prioritize areas of high management and conservation value and to help inform aquatic resources management. The resulting prioritized areas included many minimally disturbed watersheds in east Maui and western nearshore and coastal zones that are adjacent to diverse coral reefs. These results are driven by the importance of fish biomass and coral reef distribution as well as traditional wetland taro cultivation and coastal access points for recreation. These results underline the importance of examining ridge-to-reef systems for aquatic resource management and including important social and cultural values in resource management upon planning adaptation strategies for climate change. Improving our understanding of diverse natural and socio-cultural influences on habitat conditions and their values in these areas provides an opportunity to strategically plan future management and conservation actions.

Landslide hypothesis for the origin of Haleakala volcano's crater and great valleys, Hawaii

Abstract Active Haleakala volcano on the island of Maui is the second largest volcano in the Hawaiian Island chain. Prominently incised in Haleakala's slopes are four large (great) valleys. Haleakala Crater, a prominent summit depression, formed by coalescence of two of the great valleys. The great valleys and summit crater have long been attributed solely to fluvial erosion, but two significant enigmas exist in the theory. First, the great valleys of upper Keanae/Koolau Gap, Haleakala Crater, and Kaupo Gap are located in areas of relatively low annual rainfall. Second, the axes of some valley segments are oblique for long distances across the volcanic slopes. This study tested the prevailing erosional theory by reconstructing the volcano's topography just prior to valley incision. The reconstruction produces a belt along the volcano's east rift zone with a morphology that is inconsistent with volcanic aggradation alone, but it is readily explained if it is assumed the surface was displaced along scarps formed by a giant landslide on Haleakala's northeastern flank. Although the landslide head location is well defined, topographic evidence is lacking for the toe and lateral margins. Consequently, the slope failure is interpreted as a sackung-style landslide with a zone of deep-seated distributed shear and broad surface warping downslope of the failure head. Maximum downslope displacement was likely in the range of 400–800 m. Capture of runoff at the headscarps formed atypically large streams that carved Haleakala's great valleys and explains their existence in low-rainfall areas and their slope-oblique orientations. Sackung-style landslides may be more prevalent on Hawaiian volcanoes than previously recognized.

Characterizing the suitable habitat of Miconia calvescens in the East Maui Watershed

Characterizing the suitable habitat of Miconia calvescens in the East Maui Watershed

The volatile budget of Hawaiian magmatism: Constraints from melt inclusions from Haleakala volcano, Hawaii

Pre-eruptive volatile contents recorded by melt inclusions from ocean island settings such as Hawaii constrain the extent of deep Earth outgassing on geologic timescales by mantle plume activity. However, melt inclusions trapped from a partially degassed magma will not reflect the original volatile content of the primary melt, and relatively silicic (>45 wt% SiO2) shield-stage tholeiites are more likely to have been affected by degassing during fractionation at shallow depths. In contrast, magmas associated with post-shield volcanoes erupt volatile-rich melts that ascend quickly from the source region and crystallize in deep reservoirs. As a result, melt inclusions from post-shield volcanoes may be more likely to preserve undegassed melt compositions that can be used to determine the primary melt and source volatile contents. In this study, we analyzed melt inclusions from Haleakala Volcano (East Maui, Hawaii) to estimate the volatile budget of Hawaiian post-shield magmas. Melt inclusions from Haleakala contain up to 1.3 wt% CO2, 1.2 wt% H2O, and about 2000 ppm S. We calculate that melts from Haleakala were derived from a parental melt with ~0.7 wt% H2O and ~0.7 wt% CO2 and experienced ~15–40% polybaric, fluid-saturated crystallization starting at 5–7 kbar. Post-shield melt inclusions from Haleakala have H2O/Ce and CO2/Ba compositions that are intermediate between shield-stage melt inclusions from Kilauea and the alkaline North Arch Volcanic Field, which is consistent with a scenario in which primary melts from Haleakala are influenced by the volatile-rich auto-metasomatized periphery of the composite plume source.

Legal geographies and political ecologies of water allocation in Maui, Hawai‘i

Throughout the Hawaiian Islands, sugar plantations have controlled a large proportion of water resources for over a century, often leaving little water in streams to support ecosystems or Native Hawaiian cultural and agricultural practices. Recently, in Maui, Hawai‘i, community activists and lawyers representing Native Hawaiian and environmental interests have successfully reclaimed water resources for instream flow utilizing legal processes and tools such as Hawai‘i’s public trust doctrine, which has plural roots in both Hawaiian and Western legal traditions. In this paper, we use qualitative fieldwork, including interviews, participant observation, and archival data collection, to explore two recent and ongoing legal cases around water allocation in Maui: Nā Wai ‘Ehā and East Maui. The research uses legal geography and political ecology to examine the use of the public trust doctrine in challenging water allocation practices in Maui, specifically focusing on the concepts of legal pluralism and socioenvironmental hybridity. We examine the ways in which plural legal processes and precedents have developed and combined in place-specific ways, and connect legal pluralism with ideas of hybridity from nature-society geography. In keeping with the goals of political ecology, the paper examines legal processes and socioenvironmental change as inextricable and power-laden. We demonstrate that the intersection of legal geography with political ecology can contribute a stronger understanding of the context-specific dynamics of socioenvironmental change.

Contributions of native forest protection to local water supplies in East Maui

Tropical forests provide a suite of benefits including biodiversity, cultural value, and a range of ecosystem services. Globally, there is increasing interest in incentivizing native forest protection as a multi-benefit natural infrastructure strategy to secure clean and ample water supplies. In addition to conversion to agriculture and other non-forest land uses, non-native species invasion represents a major threat to these systems, particularly on islands. Whereas several recent efforts have quantified the benefits of reforestation or avoided agricultural expansion in tropical forest areas, the hydrologic and associated economic benefits of avoided invasion have received less attention. To address this gap, we quantified the benefits of protecting native forest from conversion to non-native forest in East Maui, Hawai'i in terms of groundwater recharge, a highly valued hydrologic ecosystem service that water utilities increasingly seek to co-finance. Compared with two counterfactual invasion scenarios, the groundwater recharge benefits of planned conservation activities reached 40.9 to 146.3 million cubic meters over 100 years depending on invasion rate assumptions. This translated to 2.70 to 137.6 million dollars of cost savings to the water utility in present value terms (achieved through reducing reliance on more expensive water alternatives) under a range of discount rates and water scarcity assumptions. Our results suggest that investing in native forest conservation provides an important hydrologic ecosystem service benefit that complements the range of benefits provided by these ecosystems. These findings demonstrate that co-financing native forest conservation represents an important supply side option in water resources planning.

Spider webs, stable isotopes and molecular gut content analysis: Multiple lines of evidence support trophic niche differentiation in a community of Hawaiian spiders

Abstract Adaptive radiations are typically characterized by niche partitioning among their constituent species. Trophic niche partitioning is particularly important in predatory animals, which rely on limited food resources for survival. We test for trophic niche partitioning in an adaptive radiation of Hawaiian Tetragnatha spiders, which have diversified in situ on the Hawaiian Islands. We focus on a community of nine species belonging to two different clades, one web‐building and the other actively hunting, which co‐occur in wet forest on East Maui. We hypothesize that trophic niches differ significantly both: (a) among species within a clade, indicating food resource partitioning, and (b) between the two clades, corresponding to their differences in foraging strategy. To assess niches of the spider species, we measure: (a) web architecture, the structure of the hunting tool, and (b) site choice, the physical placement of the web in the habitat. We then test whether differences in these parameters translate into meaningful differences in trophic niche by measuring (c) stable isotope signatures of carbon and nitrogen in the spiders’ tissues, and (d) gut content of spiders based on metabarcoding data. We find significant interspecific differences in web architecture and site choice. Importantly, these differences are reflected in stable isotope signatures among the five web‐building species, as well as significant isotopic differences between web‐builders and active hunters. Gut content data also show interspecific and inter‐clade differences. Pairwise overlaps of web architecture between species are positively correlated with overlaps of isotopic signature. Our results reveal trophic niche partitioning among species within each clade, as well as between the web‐building and actively hunting clades. Based on the correlation between web architecture and stable isotopes, it appears that the isotopic signatures of spiders’ tissues are influenced by architectural differences among their webs. Our findings indicate an important link between web structure, microhabitat preference and diet in the Hawaiian Tetragnatha. A free Plain Language Summary can be found within the Supporting Information of this article.

Interpreting Life-History Traits of Miconia (Miconia calvescens) through Management over Space and Time in the East Maui Watershed, Hawaii (USA)

AbstractMiconia (Miconia calvescens DC) was introduced to the East Maui Watershed (EMW) a half-century ago with more than 25 yr of management recorded. Using a historical spatiotemporal data set, we constructed a leptokurtic dispersal kernel with 99% of progeny confined to within 549 m of the nearest maternal source and the remaining 1% dispersed out to 1,636 m. Seedbank persistence, based on postdated recruitment, displayed an exponential decay projecting extinction beyond 20 yr. These parameters are highly congruent to independent interpretations of M. calvescens in Australia and Tahiti. In a simulated stage matrix model, we projected management efforts to locally eradicate a small incipient propagule bank wherein optimal management was achieved with an annual harvest rate that eliminated all juvenile recruits before reaching maturity, until extinction. Based on current pricing for helicopter herbicide ballistic technology (HBT) operations, the optimal, variable cost to locally eradicate this incipient propagule bank was estimated to be less than US$42,000, with ~90% of the effort searching for the most distant 1% of the progeny expended within the first 9 yr after the mature discovery. This variable cost was sensitive to seedbank size, recruitment rate, and dispersal range, but was most sensitive to harvest rates between suboptimal and excess. In a scenario prioritizing the upper region of EMW, we retroactively analyzed past HBT efforts eliminating satellite M. calvescens and determined that 27% of the total effort resulted in 87% of the total protection to this priority asset, with every US$1 invested potentially avoiding US$184 in future costs. Management outside the priority area was less economical, with returns in protection diminishing with distance from the priority upper region. Miconia calvescens is currently not eradicable in the EMW, and full containment of the invasion would require a substantial increase in stable, long-term funding. With limited resources, local eradication of satellite M. calvescens could be the most cost-effective alternative to protecting uninvaded areas prioritized for critical ecosystem functions.

Co-occurrence of ecologically similar species of Hawaiian spiders reveals critical early phase of adaptive radiation

BackgroundThe processes through which populations originate and diversify ecologically in the initial stages of adaptive radiation are little understood because we lack information on critical steps of early divergence. A key question is, at what point do closely related species interact, setting the stage for competition and ecological specialization? The Hawaiian Islands provide an ideal system to explore the early stages of adaptive radiation because the islands span ages from 0.5–5 Mya. Hawaiian spiders in the genus Tetragnatha have undergone adaptive radiation, with one lineage (“spiny legs”) showing four different ecomorphs (green, maroon, large brown, small brown); one representative of each ecomorph is generally found at any site on the older islands. Given that the early stages of adaptive radiation are characterized by allopatric divergence between populations of the same ecomorph, the question is, what are the steps towards subsequent co-occurrence of different ecomorphs? Using a transcriptome-based exon capture approach, we focus on early divergence among close relatives of the green ecomorph to understand processes associated with co-occurrence within the same ecomorph at the early stages of adaptive radiation.ResultsThe major outcomes from the current study are first that closely related species within the same green ecomorph of spiny leg Tetragnatha co-occur on the same single volcano on East Maui, and second that there is no evidence of genetic admixture between these ecologically equivalent species. Further, that multiple genetic lineages exist on a single volcano on Maui suggests that there are no inherent dispersal barriers and that the observed limited distribution of taxa reflects competitive exclusion.ConclusionsThe observation of co-occurrence of ecologically equivalent species on the young volcano of Maui provides a missing link in the process of adaptive radiation between the point when recently divergent species of the same ecomorph occur in allopatry, to the point where different ecomorphs co-occur at a site, as found throughout the older islands. More importantly, the ability of close relatives of the same ecomorph to interact, without admixture, may provide the conditions necessary for ecological divergence and independent evolution of ecomorphs associated with adaptive radiation.

Extinction Risk and Conservation Options for Maui Parrotbill, an Endangered Hawaiian Honeycreeper

Abstract Extinction rates for island birds around the world have been historically high. For forest passerines, the Hawaiian archipelago has suffered some of the highest extinction rates and reintroduction is a conservation tool that can be used to prevent the extinction of some of the remaining endangered species. Population viability analyses can be used to assess risks to vulnerable populations and evaluate the relative benefits of conservation strategies. Here we present a population viability analysis to assess the long-term viability for Maui parrotbill (Kiwikiu) Pseudonestor xanthophrys, a federally endangered passerine on the Hawaiian island of Maui. Contrary to indications from population monitoring, our results indicate Maui parrotbills may be unlikely to persist beyond 25 y. Our modeling suggests female mortality as a primary factor driving this decline. To evaluate and compare management options involving captive-rearing and translocation strategies we made a female-only stage-structured, meta-population simulation model. Maui parrotbills have low reproductive potential in captivity; therefore, the number of individuals (∼20% of the global population) needed to source a reintroduction solely from captive reared birds is unrealistic. A reintroduction strategy that incorporates a minimal contribution from captivity and instead translocates mostly wild individuals was found to be the most feasible management option. Habitat is being restored on leeward east Maui, which may provide more favorable climate and habitat conditions and promote increased reproductive output. Our model provides managers with benchmarks for fecundity and survival needed to ensure reintroduction success, and highlights the importance of establishing a new population in potentially favorable habitat to ensure long-term persistence.

Athyrium haleakalae (Athyriaceae), a new rheophytic fern species from East Maui, Hawaiian Islands: with notes on its distribution, ecology, and conservation status

Athyrium haleakalae K.R. Wood & W.L. Wagner (Athyriaceae), a small lithophytic fern from East Maui, Hawaiian Islands, is described and illustrated. Notes on its distribution, ecology, and conservation status are also presented. The new species appears to be an obligate rheophyte, preferring sites of fast moving water along concave walls of streams and waterfalls. Athyrium haleakalae differs from the only other known Hawaiian Athyrium, Athyrium microphyllum (Sm.) Alston, in having rhizomes 1–3 cm long and lanceolate blades 1- to 2-pinnate-pinnatifid, 3–8(–11) × 1–3(–4) cm, as compared to Athyrium microphyllum having rhizomes (10–)15–30 cm long and ovate to ovate-triangular blades 3-pinnate-pinnatifid to 4-pinnate, 30–82 × 20–50 cm.

The East Maui Irrigation System

The irrigation system on the Hawaiian island of Maui channeled water from the rainy windward side to the flatter leeward side, where profitable sugarcane could then be grown.

Herbicide Ballistic Technology: Spatial Tracking Analysis of Operations Characterizing Performance of Target Treatment

<abstract> <b><sc>.</sc></b> Since 2012, the Herbicide Ballistic Technology (HBT) platform has been deployed in helicopter operations with a mission to eliminate nascent populations of the invasive plant species miconia ( DC), which is spreading across the East Maui Watershed in Hawaii. The HBT platform is a refined pesticide application system that pneumatically delivers encapsulated herbicide projectiles (i.e., paintballs) from a long range (up to ~30 m) and varying attitude. This onboard system provides accurate, effective treatment of individual plant targets occupying remote, inaccessible portions of the forested landscape. Statistics of operational performance are acquired through GIS analyses of recorded GPS data assigned to treated plant targets. Recently, we have developed a telemetry system for HBT applications (HBT-TS) to enhance the attribute data of target treatments. The HBT-TS integrates a hardware sensor with the electro-pneumatic marker that is actuated by the trigger to generate time-stamped, geo-referenced attribute data, including target assignment, azimuth, tilt, and range determined from the applicator position, for every projectile discharged. With target assignments, the HBT-TS records the estimated dose applied to each target. Furthermore, the time stamps show that the actual time to administer projectiles (i.e., target treatment) is a minor component of the total time on target. By tracking the orientation and distance of the discharged projectile, we can calculate a precise offset target location relative to the applicator position and provide a more accurate interpretation of the herbicide use rate (g acid equivalent ha^-1) based on the known amount of herbicide contained in each projectile and the final placement on the landscape. We acknowledge the challenges of GPS inaccuracies while recording in a dynamic environment (i.e., a moving platform in extreme topography), albeit with increased precision. Regardless, the current state of the HBT-TS technology enhances operational intelligence relevant to landscape-scale invasive species management.

New and resurrected Hawaiian species of pilo (Coprosma, Rubiaceae) from the island of Maui.

Two species of Coprosma (Rubiaceae) J.R.Forst. & G.Forst. are described from the island of Maui of the Hawaiian Archipelago. A newly described taxon, Coprosma cordicarpa J.Cantley, Sporck-Koehler, & M.Chau, sp. nov. is locally common in medium to high elevation dry forests and shrublands of leeward East Maui. The second taxon is resurrected from the synonymy of Coprosma foliosa A.Gray as Coprosma stephanocarpa Hillebr. and occurs in mesic to wet rainforests of both East and West Maui. Both taxa are segregated from Coprosma foliosa, with which they share similar morphological characters. A conspicuous and persistent calyx of the fruit and various floral characters most easily differentiate both taxa from other Hawaiian taxa. The newly described Coprosma cordicarpa is further distinguished from Coprosma stephanocarpa by a central constriction of the fruit with a depressed apex, which gives it a characteristic heart shape. Furthermore, the taxa are largely separated phenologically, ecologically, and geographically. Descriptions, conservation status, and specimens examined for the new species are included.