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Expert knowledge is widely used for assessing the conservation status of little-known species. Pterocymbium oceanicum is a large, emergent tree endemic to Fiji. Experts classified the species as 'Critically Endangered' (IUCN Red List) in 2016 and estimated the population size at <250 mature individuals with the largest subpopulation consisting of a single stand of 100 individuals. We surveyed this stand and counted 133 individuals, which validated the expert estimate. However, we discovered an additional three stands nearby, increasing the total subpopulation size to 433 individuals. Therefore, the expert estimate reliably and conservatively estimated population size but missed important information. Field surveys suggest that P. oceanicum has a narrow ecological niche as a long-lived early pioneer at mid-elevations (400–800 m) in seasonally dry forests, one of Fiji's most degraded ecosystems. The introduced African Tulip Tree, Spathodea campanulata , is invading the sampled subpopulation and shares the characteristics of being a large, fast-growing and early successional tree. Therefore, the narrow niche of P. oceanicum may now be threatened by S. campanulata. Our study highlights that expert knowledge can provide valuable information about threatened species but also has limitations. IUCN Red List assessments based solely on expert assessments should therefore be cautiously interpreted. The invasion by S. campanulata poses a serious threat to P. oceanicum and needs to be carefully monitored, with the impacts of S. campanulata on the establishment and growth of P. oceanicum requiring urgent investigation. Pterocymbium oceanicum is a large, emergent tree endemic to Fiji that was classified as 'Critically Endangered' (IUCN Red List) based on expert knowledge. Our field survey quadruples the known size of the largest subpopulation by discovering three previously unknown stands, highlighting the value and limitations of expert knowledge for conservation assessments. Furthermore, we found that the species has a narrow ecological niche and is potentially threatened by the invading African Tulip Tree, Spathodea campanulata , which should be carefully monitored. [ABSTRACT FROM AUTHOR]

Despite worldwide knowledge of the importance of the Galápagos archipelago, there is little comparative plot data from the forests in the dry regions. We examined patterns of woody plant (≥2.5 cm diameter at breast height (DBH)) species richness and structure using Gentry's transect method (0.1 ha) on the three largest islands in the Galápagos. We identified the conservation status of woody plants within the dry forest region, assessed forest cover and change in the region, and compared field results to other tropical dry forests in the Pacific. Of the 22 species encountered (11 native, 11 endemic), there were no non-native species and only one threatened species. Isabela, Santa Cruz and San Cristóbal have similar overall levels of species, genera, family and liana richness per site, but significantly different tree species richness, density and tree height per transect. Geospatial databases identified 51 species (native 40%, endemic 60%) of woody plants (≥2.5 cm DBH) within the dry forest region of the Galápagos and 13 species (10 from the genus Scalesia) on the IUCN Red List. There is an estimated 551.97 km2 of dry forest in the Galápagos and there has been little change (<0.01%) in forest cover from 2000 to 2015. Dry forests of the Galápagos have similar levels of species richness to Hawaii and the Marquesas but contain lower densities, basal areas and tree heights than other dry forests in the Pacific. These dry forests appear to be the best preserved and protected tropical dry forest in the Pacific. This research examines patterns of woody plant species richness and structure in dry forests on the three largest islands in the Galápagos. We identify the conservation status of woody plants within the dry forest region, assess forest cover change, and compare results to other tropical dry forests in the Pacific. [ABSTRACT FROM AUTHOR]

Half of Fiji's 66 land bird species are endemic and 15 species are threatened with extinction following ~70% deforestation. Under conditions of large-scale habitat loss, secondary vegetation can be important for woodland biodiversity conservation. This study compares avian abundance and diversity in secondary vegetation on Viti Levu, Fiji. We use avian point surveys at replicate sites in regenerating mahogany plantation (Colo-i-Suva; eastern lowlands), regenerating native forest (Koroyanitu National Heritage Park; western highlands) and grassland (Koroyanitu National Heritage Park). We ask if there are differences in avian abundance and species richness across habitat types. In total, we recorded 1063 birds from 33 bird species. Regenerating forest sites had the greatest species richness with mostly endemic and native woodland bird species and few introduced species. Regenerating plantation sites harboured a comparable number of endemic species and threatened species as regenerating forest sites but had significantly fewer native species and no introduced species. We recorded the most birds at grassland sites as well as the most introduced species. The findings of this study underscore the importance of regenerating native forest and regenerating plantation as habitats for Fiji's endemic woodland birds. Increasing the expanse of regenerating forest sites should be considered for conservation planning to sustain Fiji's extant birds. [ABSTRACT FROM AUTHOR]

In many developing countries, threatened species lists are unavailable and IUCN Red Lists are very incomplete. Because limited resources are available for conservation in developing countries, detailed field assessments and scientific study of threatened species are often not feasible. However, considerable knowledge about biodiversity exists among experts and local land users. We used questionnaires as part of field surveys to compile information about the abundance, conservation threats, distribution, and ecology of populations of four threatened and iconic target species in Fiji (Acmopyle sahniana, Dacrydium nausoriense, Podocarpus affinis [all Podocarpaceae], and Cynometra falcata [Leguminosae]). These questionnaires were completed in the field for all known populations by an assessor, compiling field observations and measurements with information from local land users and local and outside experts. For the four species in this study, the questionnaires improved estimates of population size, identified previously unknown populations, provided estimates of regeneration, and identified key conservation threats. Species of highly fragmented remnants in drier climates were less protected than those in more contiguous forests of moist climates. The methods employed provided rapid, cost-effective information that can be used to revise IUCN Red List and conservation status assessments and are applicable to other Pacific Island and developing countries. [ABSTRACT FROM AUTHOR]

To identify forests of high priority for conservation in tropical dry forests of New Caledonia, Fiji, the Marquesas and Hawaii, we examined patterns of woody plant species richness (total, native and endemic) and threatened species (IUCN categorization and density) at the stand level, using Gentry's transect method. There were associations between total, native and endemic plant species richness in all four Pacific dry forest regions but we found no significant association with the presence or density of species listed on the IUCN Red List. Dry forests in New Caledonia and Hawaii merit the highest conservation priority in the Pacific, based on level of endemism and number of threatened species. The study sites that merit high conservation priority are Metzdorf, Nekoro and Pindai, in New Caledonia, Kokee and Kaupulehu, in Hawaii, and Vatia, in Fiji. New Caledonia and Fiji have a small dry forest extent and protected area extent compared with other dry forests in biodiversity hotspots. Although we identified priority areas for dry forest conservation, more comparative plot data, presence/absence data in fragments and regional geographical data are needed to adequately manage and protect dry forests in the Pacific. [ABSTRACT FROM AUTHOR]