Pacific Science, Volume 64, Numbers 1-4, 2010

Origins and Nature of Vessels in Monocotyledons. 12. Pit Membrane Microstructure Diversity in Tracheary Elements of Astelia.

Carlquist, Sherwin; Schneider, Edward L. — Fri, 01 Oct 2010 00:00:00 GMT

Xylem of stems and roots of three species of Astelia, a monocot with relatively unspecialized xylem, was examined with scanning electron microscopy (SEM) to better understand structural conditions intermediate between tracheids and vessel elements. Both macerations and hand-sectioned material were studied. Tracheary elements of roots of Asteliaceae can be characterized as tracheids with some degrees of transition to vessel elements. Pit membrane remnants, which take the form of pores, reticula, or threads, are present commonly in end walls of tracheary elements of roots of Astelia. Stems of Astelia have tracheids with less-conspicuous porosities in the pit membranes of end walls than those of roots. Sectioned materials show that the porose (reticulate) cellulosic layers of the primary wall, which is embedded in a matrix of amorphous material, can be exposed to various degrees by the sectioning process; the cellulosic network faces the lumen, and the amorphous material is the compound middle lamella. Astelia shows stages of transition between vessel elements and tracheids. These character expressions relate to occupancy of moist habitats (Astelia) with steady availability of moisture during the year. There appears to be little difference between a terrestrial species (A. chathamica) and the scandent/epiphytic species A. argyrocoma and A. menziesiana in terms of tracheary element microstructure, suggesting that habitat is more important than habit as a determinant of tracheary element microstructure and the degree to which lysis of pit membranes occurs. Freehand sectioning of ethanol-fixed materials, as in earlier studies in this series, provides a reliable way of observing pit membrane/ perforation structure when viewed with SEM. Astelia is one of several monocots that demonstrate the difficulty of discriminating between tracheids and vessel elements. v. ill. 23 cm.; Quarterly

Marine Benthic Algae of Johnston Atoll: New Species Records, Spatial Distribution, and Taxonomic Affinities with Neighboring Islands.

Tsuda, Roy T.; Abbott, Isabella A.; Vroom, Peter S.; Fisher, Jack R. — Fri, 01 Oct 2010 00:00:00 GMT

Forty-five of the 107 species of marine benthic algae collected during 2004 and 2006 NOAA cruises to isolated Johnston Atoll and two additional species from earlier collections represent new species records. Total number of algae is now increased to 189 species: 26 species of cyanobacteria ( blue-green algae), 105 species of red algae, 15 species of brown algae, and 43 species of green algae. The macroalga Caulerpa serrulata and the epiphyte Lomentaria hakodatensis were the most widely distributed species at Johnston Atoll based on frequency of occurrence at 10 of 12 stations and 8 of 12 stations, respectively, during the 2004 NOAA cruise. Despite the atoll’s isolation, the parasitic red alga Neotenophycus ichthyosteus and the cyanobacterium Borzia elongata are the only endemic algal species on Johnston Atoll. Nonmetric multidimensional scaling analyses indicate that taxonomic affinities of Johnston Atoll lie between French Frigate Shoals and Wake Atoll. In terms of atolls, biodiversity of the marine flora of Johnston Atoll (i.e., 189 species) is surpassed only by the 256 algal species of the much-larger and better-studied Enewetak Atoll in the Marshall Islands. v. ill. 23 cm.; Quarterly

Review of Crocodile (Reptilia: Crocodilia) and Dugong (Mammalia: Sirenia) Sightings in the Federated States of Micronesia.

Buden, Donald W.; Haglelgam, John — Fri, 01 Oct 2010 00:00:00 GMT

Three confirmed occurrences of crocodiles, one identified as Crocodylus porosus (two others presumed C. porosus), and four occurrences of the dugong, Dugong dugon, are recorded for the Federated States of Micronesia. The records of a crocodile and a dugong on Eauripik Atoll and a dugong on Kosrae are reported in the literature for the first time. On geographic grounds, the crocodiles and dugongs recorded from Yap State, in the western part of the FSM, probably pertain to vagrants from Palau, approximately 450 km to the southwest, whereas those recorded from the eastern islands (Pohnpei and Kosrae) are more likely to have originated from populations in the Bismarck Archipelago and Solomon Islands area, approximately 1,500 km to the southwest, rather than from Palau, which is a much greater distance to the west. v. ill. 23 cm.; Quarterly

Records of Great White Sharks (Carcharodon carcharias) in New Caledonian Waters.

Fri, 01 Oct 2010 00:00:00 GMT

The occurrence of great white sharks (Carcharodon carcharias) in New Caledonia is documented from 30 observation events (sightings or captures or forensic examination of wounds) made between 1943 and 2009, involving 34 individual sharks. Nine of the observation events concerned animals caught on lines set for deep-sea fishes, five were encounters with scuba divers or snorkelers, and one was a fatal attack on a surfer; two other observations included great white sharks feeding on whale carcasses; two were from pop-up archival transmitting tag records that monitored individuals tagged in the Chatham Islands, New Zealand; one was a forensic identification from wounds sustained by another large shark; and seven were fortuitous sightings from boats. Nearly all observations were of solitary sharks. Observation events were concentrated in the southern lagoon of New Caledonia or along its barrier reef. They occurred from July to March, with most records in September and November, coinciding with a peak of occurrence of large cetaceans. v. ill. 23 cm.; Quarterly

Impacts of Recreational Divers on Palauan Coral Reefs and Options for Management.

Poonian, Chris; Davis, Patricia Z. R.; McNaughton, Colby Kearns — Fri, 01 Oct 2010 00:00:00 GMT

Recent growth in the popularity of recreational scuba diving has generated concerns about resulting impacts to coral reefs, particularly in locations such as the Republic of Palau, a world-renowned dive destination with rapidly increasing numbers of visitors. Divers were observed in-water at three of the most visited dive sites in the Rock Islands–Southern Lagoon Area: German Channel, Ngerchong, and Big Drop-off. Dive guides were interviewed about diver impacts at German Channel and Ngerchong. Divers’ contact rates with hard coral ranged from 0.87e0.27 to 2.98e0.59 contacts diver_1 10 min_1 (meaneSEM). Three instances of obvious physical damage were observed. Holding and fin contacts were the most common potentially damaging behaviors of divers, particularly those with cameras or gloves. Guides identified natural impacts (63% of respondents) and divers (34% of respondents) as the primary causes of damage to coral. Proactive management is essential to mitigate any negative impacts of recreational diving on coral reefs and to ensure resilience against other increasing threats. Long-term monitoring of dive sites, controls on the use of gloves and underwater photography, and training of guides are suggested to minimize damage caused by divers to coral reefs in Palau and elsewhere. v. ill. 23 cm.; Quarterly

Comparison of Dissolved Organic Carbon Bioavailability from Native and Invasive Vegetation along a Hawaiian River.

Wiegner, Tracy N.; Tubal, Randee L. — Fri, 01 Oct 2010 00:00:00 GMT

Riparian litter fall is an important source of organic matter to rivers and accounts for a large fraction of their dissolved organic carbon (DOC) load. DOC is metabolically important in rivers, and therefore changes in riparian vegetation species composition should affect riverine DOC bioavailability. Worldwide, invasive vegetation composes a large percentage of riparian vegetation. In Hawai‘i, riparian vegetation changes from native to invasive species with decreasing elevation. To assess how changes in riparian vegetation affect riverine DOC dynamics, we compared DOC bioavailability from native (Acacia koa and Metrosideros polymorpha) and invasive (Falcataria moluccana and Psidium cattleianum) riparian trees to freshwater and estuarine bacteria from the Wailuku River on Hawai‘i Island through dark bioassays. DOC bioavailabilities in riverine and estuarine waters were similar among all riparian vegetation types. In contrast, vegetation-derived DOC was more bioavailable (52%e4%) than the riverine and estuarine DOC (14%e3%). Combining DOC bioavailability and leaf litter input data from our native and invaded riparian sites suggests that a shift in leaf litter inputs from native to invasive species may increase the amount of bioavailable DOC entering Hawaiian rivers and streams. This DOC input has the potential to impact the metabolism and food webs of downstream ecosystems. v. ill. 23 cm.; Quarterly

Native Species Regeneration Following Ungulate Exclusion and Nonnative Grass Removal in a Remnant Hawaiian Dry Forest.

Fri, 01 Oct 2010 00:00:00 GMT

Hawaiian lowland dry forests have been reduced by >90% since first human contact. Restoration has focused on protection from fire and ungulates, and removal of invasive grasses as ways to stimulate native forest regeneration. Despite these efforts, natural regeneration of native plants has been infrequent. To assess effects of previous restoration treatments on natural regeneration, we monitored seed rain and dynamics of seedlings and juveniles for a period of 3 yr (2004–2007) within three restoration units within a remnant forest on the island of Hawai‘i. All units had been protected from fire for many decades but differed in time since ungulate exclusion and grass removal. The units were as follows: (1) long-term restoration (fenced 1956, grass removal initiated 1995), (2) shortterm restoration (fenced and grass removal initiated 1997), and (3) unmanaged (fenced 1997, no grass removal). Overall juvenile plant abundance was highest in the short-term unit, but native abundance was highest in the long-term unit. Native woody seedlings established in all units, but recruitment into larger size classes was restricted to units with grass removal, primarily the long-term unit. Native seed rain explained much of the variation in native seedling abundance between units with grass removal. Nonnative grass seed rain was extensive but was reduced by an order of magnitude with grass removal. This study suggests that natural regeneration may enhance restoration actions in sites with native canopy, but this is likely only when restoration activities have been maintained for several years to coincide with favorable rainfall conditions that are highly unpredictable over time. v. ill. 23 cm.; Quarterly

Can Ptilinopus greyii (Columbidae) Disperse Seeds in New Caledonia’s Dry Forests?

Tassin, Jacques; Boissenin, Melanie; Barre, Nicolas — Fri, 01 Oct 2010 00:00:00 GMT

Conservation of endangered habitats of South Pacific islands is partially dependent on activity of seed dispersers. In consuming fruits, animals can spread seeds from parent plants to distant sites, thus contributing to plant regeneration and colonization of new sites. In the dry forests of New Caledonia, the red-bellied fruit-dove, Ptilinopus greyii, is a potential disperser of many fleshyfruited species. Trials with a captive bird showed that gut passage enhanced seed germination for Diospyros fasciculosa and Mimusops elengi but not for Vitex cf. collina, compared with whole fruits. Gut passage did not shorten duration of seed dormancy, which is consistent with evidence of a simple deinhibition effect for D. fasciculosa and M. elengi. Minimum Retention Time (MRT) of seeds in the gut differed significantly between the three tree species, from a mean of 17.4 min for D. fasciculosa to a mean of 52.4 min for M. elengi. These times are longer than observed foraging times in fruiting trees, potentially making this fruit-dove an effective seed disperser. v. ill. 23 cm.; Quarterly

Biology and Impacts of Pacific Island Invasive Species. 6. Prosopis pallida and Prosopis juliflora (Algarroba, Mesquite, Kiawe) (Fabaceae).

Gallaher, Timothy; Merlin, Mark — Fri, 01 Oct 2010 00:00:00 GMT

Prosopis pallida and P. juliflora (commonly referred to as algarroba, mesquite, or kiawe) were introduced from South America to areas in Oceania, Asia, and Africa during the early nineteenth century. In many cases, they naturalized and became widespread. In some places, alien Prosopis species are highly valued for the products and services that they can provide such as shade, cattle fodder, wood for fuel and fence posts, and nectar for honey production. In Australia, four Prosopis species including P. pallida, P. juliflora, P. glandulosa, P. velutina, and their hybrids are considered invasive and are subject to control efforts. After its introduction to Hawai‘i in 1828, P. pallida became a dominant tree in arid areas of the main Hawaiian Islands, replacing the native lowland dry forest species that had been decimated by human activity, particularly by the introductions of goats and cattle. Prosopis pallida also has become an important economic species in Hawai‘i. Prosopis juliflora, a more recent introduction to Hawai‘i, is now spreading and is considered to be a noxious weed. Competition between Prosopis and native species as well as negative impacts of Prosopis on soil and local hydrology have been reported; however in some cases Prosopis species are characterized as midsuccessional species that rehabilitate degraded soils, eventually facilitating later-successional woodland. This provides a potential opportunity to use these species in reforestation efforts. Management decisions regarding these species should include a consideration of both their positive and negative ecological roles. If control or eradication is desired, a number of methods have been employed with various degrees of success. v. ill. 23 cm.; Quarterly

Reptiles of Ngulu Atoll, Yap State, Federated States of Micronesia.

Buden, Donald W. — Thu, 01 Jul 2010 00:00:00 GMT

Fourteen species of reptiles (two sea turtles, six geckos, six skinks) are recorded from Ngulu Atoll, Yap, Micronesia, all but the turtles for the first time. None is endemic and most occur widely in Oceania; the phylogenetic status of an undescribed species of Lepidodactylus is undetermined, and a phenotypically male Nactus cf. pelagicus is recorded from Micronesia for the first time. Lepidodactylus moestus is the most common gecko on Ngulu Island, and Emoia caeruleocauda, E. impar, and E. jakati are the most abundant skinks. The islands are an important nesting site for green turtles, Chelonia mydas. Isolation, a small resident human population, and traditional conservation practices contribute to sustaining turtle populations, although occasional poaching by outside visitors persists. The report of a small snake on Ylangchel Island, possibly a species of Ramphotyphlops, requires confirmation. v. ill. 23 cm.; Quarterly

Protodrilidae (Annelida: Polychaeta) from the Hawaiian Islands and Comparison with Specimens from French Polynesia.

Bailey-Brock, Julie H.; Jouin-Toulmond, Claude; Brock, Richard E. — Thu, 01 Jul 2010 00:00:00 GMT

Three species of Protodrilidae were collected from the islands of O‘ahu and Ni‘ihau in the Hawaiian chain, including specimens closely resembling Parenterodrilus taenioides ( Jouin, 1979), described from Mo‘orea (French Polynesia). Others are probably an undescribed species of Parenterodrilus that was found in fine sand substrate collected off Wai‘anae, O‘ahu. A third species, Protodrilus albicans Jouin, 1970, described from Banyuls-sur-Mer (Mediterranean Sea) and recorded from Mo‘orea and Tahiti as well, was also collected from O‘ahu. Depths and habitat characteristics are given for these new records to the Hawaiian fauna. It is suggested that the wide geographical distribution of the different ‘‘cosmopolitan species’’ of Protodrilidae is related both to the dispersal by free-swimming larvae and to the ancient origin of this interstitial fauna. v. ill. 23 cm.; Quarterly

Occurrence of the Phoronid Phoronopsis albomaculata in Cocos Island, Costa Rica.

Dean, Harlan K.; Sibaja-Cordero, Jeffrey A.; Cortes Jorge — Thu, 01 Jul 2010 00:00:00 GMT

The phoronid Phoronopsis albomaculata was collected in subtidal (28– 35 m) sandy sediments in Bahı´a Chatham during a benthic survey designed to describe the biota of Cocos Island (Isla del Coco), Costa Rica, a national park and Human Heritage Site. Occurrence of this widespread species in Cocos Island is the first report of a phoronid for Costa Rican waters and is the second locality recorded for the eastern Pacific. Taxonomically significant characters (presence of an epidermal collar, extent of coiling of lophophore and nephridia) are discussed. Comparisons are made between depth and abundance of this species from Cocos Island and results of previous studies. v. ill. 23 cm.; Quarterly

Rare Sightings of a Bryde’s Whale (Balaenoptera edeni) and Sei Whales (B. borealis) (Cetacea: Balaenopteridae) Northeast of O‘ahu, Hawai‘i.

Smultea, Mari A.; Jefferson, Thomas A.; Zoidis, Ann M. — Thu, 01 Jul 2010 00:00:00 GMT

In the Hawaiian Islands small numbers of Bryde’s whales (Balaenoptera edeni) have been documented only in the Northwestern (leeward) Hawaiian Islands, and sei whales (B. borealis) have only recently been confirmed near the islands of Maui and Hawai‘i. In November 2007, one Bryde’s whale and two sei whale groups (including three subadults) were documented during a 7-day, systematic vessel-transect survey conducted east and northeast of O‘ahu. The Bryde’s whale sighting is the first in nearshore (<70 km) waters of the main Hawaiian Islands, and the two sei whale sightings are the first near O‘ahu, including the first documented subadult sei whales there. The latter information suggests that Hawai‘i may be a reproductive area for the endangered sei whale, whose breeding and calving ground locations remain unknown in the Pacific Ocean. Other than rare incidence, the lack of historical sightings of these two species despite many years of previous shipboard and aerial surveys off Hawai‘i may be due to misidentification and/or poor sea conditions prevalent in deep, offshore windward waters of the Hawaiian Islands. We recommend conducting more offshore vessel surveys for, and biopsy sampling of, these species to clarify habitat use and current stock boundaries and numbers, information important for management of Pacific populations. v. ill. 23 cm.; Quarterly

Microhabitat Distribution of the Hermit Crabs Calcinus haigae and Calcinus hazletti (Decapoda: Anomura: Diogenidae).

Hazlett, Brian A.; Bach, Catherine E. — Thu, 01 Jul 2010 00:00:00 GMT

Two sympatric species of hermit crabs, Calcinus haigae and Calcinus hazletti, appear to have different microhabitat distributions in the subtidal. Several biotic factors may be influencing this microhabitat difference. We documented the field distributions of these two species as a function of coral species and investigated whether aggregation behavior, avoidance behavior, and/or shell exchanges are influencing the distribution patterns. Individuals of C. hazletti occurred predominantly on the cauliflower coral Pocillipora meandrina. In addition, individuals of C. hazletti aggregated toward conspecifics in the laboratory. Individuals of C. haigae avoided individuals of C. hazletti in the field unless the C. haigae were in damaged shells. Individuals of C. haigae did not initiate interspecific shell exchange attempts in the laboratory, but individuals of C. hazletti did initiate interspecific shell exchanges. Thus, both intraspecific and interspecific interactions affect the distributions of these crabs. v. ill. 23 cm.; Quarterly

Review of Octocorallia (Cnidaria: Anthozoa) from Hawai‘i and Adjacent Seamounts. Part 3: Genera Thouarella, Plumarella, Callogorgia, Fanellia, and Parastenella.

Cairns, Stephen D. — Thu, 01 Jul 2010 00:00:00 GMT

Ten species of Hawaiian primnoids are described and/or discussed, completing the review of the 28 primnoids known from the Hawaiian Islands. This family constitutes 29% of the Hawaiian octocoral fauna. Callogorgia americana is synonymized with C. gilberti, resulting in a disjunct distribution in the Pacific and Northwest Atlantic. Two new species are described (Plumarella circumoperculum Cairns and Parastenella bayeri Cairns), and two (Callogorgia gilberti and C. robusta) are reported for the first time since their original descriptions over a century ago. Keys are provided for the Hawaiian primnoid genera and all species of the genus Parastenella; comparative tables are provided for the Hawaiian Callogorgia and Fanellia. A distinctive nematocyst pad is described for the genus Parastenella. Highly modified polyps caused by copepod parasites are described for two species: Callogorgia gilberti and Thouarella hilgendorfi. v. ill. 23 cm.; Quarterly

Reproductive Synchrony in Acropora Assemblages on Reefs of New Caledonia.

Baird, Andrew H.; Kospartov, Marie C.; Purcell, Steven — Thu, 01 Jul 2010 00:00:00 GMT

Despite a recent expansion in the geographical focus of studies on coral reproduction, there remain many regions in the Indo-Pacific, such as Melanesia, where research is limited. For example, although New Caledonia in southern Melanesia is home to the world’s second largest barrier reef, which has recently been given UNESCO World Heritage listing, almost nothing is known of the reproductive biology of the coral fauna there, in particular the timing of spawning. In this study we sampled Acropora assemblages in November 2004 to test for reproductive synchrony at eight sites in New Caledonia separated by up to 200 km. In total, 80% of 1,055 Acropora colonies sampled contained mature oocytes, and 34 (92%) of 37 species sampled had at least one mature colony. These data demonstrate that reproduction in Acropora is highly synchronous over a large scale in New Caledonia and suggest a multispecies spawning event following the full moon in November coincident with the mass spawning period on the Great Barrier Reef, Australia. The high synchrony of reproductive effort implies that even a brief halt of activities that threaten fertilization and early development of coral propagules, such as discharge of liquid waste from ore processing, could have a major mitigating effect on the potential damage to these globally valued reefs. v. ill. 23 cm.; Quarterly

Changes in Benthic Macrofauna Associated with a Shallow-Water Hydrothermal Vent Gradient in Papua New Guinea.

Karlen, David J.; Price, Roy E.; Pichler, Thomas; Garey, James R. — Thu, 01 Jul 2010 00:00:00 GMT

Infaunal macroinvertebrates were characterized along an environmental gradient from a shallow-water hydrothermal vent located at Tutum Bay, Ambitle Island, Papua New Guinea. Samples were collected at three sites located at 7.5, 60, and 150 m from the vent and from a nonhydrothermal reference site located to the north. Temperature and arsenic concentration were found to decrease and pH increased with distance away from the vent. At each site, five replicate core samples were taken randomly from a 1 m2 sampling grid. All infaunal invertebrates >500 mm were sorted, identified to the lowest practical taxonomic level and counted. Results from the macrofauna data show a strong trend of increasing abundance, species richness and diversity relative to distance away from the vent, but even at 150 m the benthic macrofauna appeared to be depressed relative to the reference site. Mollusks were completely absent 7.5 m from the vent, rare at 60 m, and abundant at 150 m, suggesting that the low pH values associated with the hydrothermal activity play an important role in the benthic community structure. v. ill. 23 cm.; Quarterly

Survival of Feral Cats, Felis catus (Carnivora: Felidae), on Mauna Kea, Hawai‘i, Based on Tooth Cementum Lines.

Thu, 01 Jul 2010 00:00:00 GMT

Feral cats (Felis catus) have spread throughout anthropogenic and insular environments of the world. They now threaten many species of native wildlife with chronic depredation. Knowledge of feral cat population dynamics is necessary to understand their ecological effects and to develop effective control strategies. However, there are few studies worldwide regarding annual or lifetime survival rates in remote systems, and none on Pacific islands. We constructed the age distribution and estimated survival of feral cats in a remote area of Hawai‘i Island using cementum lines present in lower canine teeth. Our data suggest annual cementum line formation. A log-linear model estimated annual survivalb1 yr of age to be 0.647. Relatively high survival coupled with high reproductive output allows individual cats to affect native wildlife for many years and cat populations to rebound quickly after control efforts. v. ill. 23 cm.; Quarterly

Potential Effects of an Invasive Nitrogen-Fixing Tree on a Hawaiian Stream Food Web.

Atwood, Trisha B.; Wiegner, Tracy N.; Turner, Jason P.; MacKenzie, Richard A. — Thu, 01 Jul 2010 00:00:00 GMT

Falcataria moluccana (albizia) is an exotic nitrogen (N)-fixing tree currently invading riparian forests in Hawai‘i, U.S.A. This study examined how this invasion is impacting stream ecosystems by using naturally occurring stable isotopes of carbon (C) and N to compare food web structure between a noninvaded and an albizia-invaded stream reach on the island of Hawai‘i. Isotopic signatures of particulate organic matter (POM), macroalgae, invertebrates, and fishes were collected and compared between the two stream reaches. Stable C isotopic signatures of organic matter sources (POM and macroalgae) and consumers (amphipods, caddisflies, crayfish, and fishes) from the invaded site were depleted in 13C compared with the noninvaded site. In contrast, all samples from the invaded site were enriched in 15N compared with the noninvaded site. Results from IsoSource and two-source mixing models suggested that albizia was a major contributor to diets of lower-level consumers within the invaded site, displacing POM and macroalgae as their major food sources. Albizia was also an indirect C and N source for higher-level consumers within the invaded site because albizia was the major dietary constituent of their prey. In addition, 15N enrichment of the macroalgae at the invaded site suggests that albizia may be an important N source to benthic primary producers and could be further altering the food web from bottom up. Our study provides some of the first evidence that invasive riparian N-fixing trees can potentially alter the structure of stream food webs. v. ill. 23 cm.; Quarterly

Top-Down Analysis of Forest Structure and Biogeochemistry across Hawaiian Landscapes.

Thu, 01 Jul 2010 00:00:00 GMT

Technical and analytical improvements in aircraft-based remote sensing allow synoptic measurements of structural and chemical properties of vegetation across whole landscapes. We used the Carnegie Airborne Observatory, which includes waveform light detection and ranging (LiDAR) and high-fidelity imaging spectroscopy, to evaluate the landscapes surrounding four well-studied sites on a substrate age gradient across the Hawaiian Islands. The airborne measurements yielded variations in ground topography, canopy height, and canopy nitrogen (N) concentration more accurately than they could have been obtained by any reasonable intensity of ground-based sampling. We detected spatial variation in ecosystem properties associated with the properties of different species, including differences in canopy N concentrations associated with the native species Metrosideros polymorpha and Acacia koa, and differences brought about by invasions of the biological N fixer Morella faya. Structural and chemical differences associated with exotic tree plantations and with dominance of forest patches by the native mat-forming fern Dicranopteris linearis also could be analyzed straightforwardly. This approach provides a powerful tool for ecologists seeking to expand from plot-based measurements to landscape-level analyses. v. ill. 23 cm.; Quarterly