Late Holocene relative sea-level reconstructions are commonly generated using proxies preserved in salt-marsh and mangrove sediment. These depositional environments provide abundant material for radiocarbon dating in the form of identifiable macrofossils (salt marshes) and bulk organic sediment (mangroves). We explore if single-step graphitization of these samples in preparation for radiocarbon dating can increase the number and temporal resolution of relative sea-level reconstructions without a corresponding increase in cost. Dating of salt-marsh macrofossils from the northeastern United States and bulk mangrove sediment from the Federated States of Micronesia indicates that single-step graphitization generates radiocarbon ages that are indistinguishable from replicates prepared using traditional graphitization, but with a modest increase in error (mean/maximum of 6.25/15 additional 14C yr for salt-marsh macrofossils). Low 12C currents measured on bulk mangrove sediment following single-step graphitization likely render them unreliable despite their apparent accuracy. Simulated chronologies for six salt-marsh cores indicate that having twice as many radiocarbon dates (since single-step graphitization costs ∼50% of traditional graphitization) results in narrower confidence intervals for sample age estimated by age-depth models when the additional error from the single-step method is less than ∼50 14C yr (∼30 14C yr if the chronology also utilizes historical age markers). Since these thresholds are greater than our empirical estimates of the additional error, we conclude that adopting single-step graphitization for radiocarbon measurements on plant macrofossils is likely to increase precision of age-depth models by more than 20/10% (without/with historical age markers). This improvement can be implemented without additional cost.

The present study enhances knowledge of the biodiversity of diatoms in Chuuk, Micronesia following our 2018 study on the seaweed-associated diatoms. We collected planktonic samples of diatoms from five sites of reef flats using a 20 μm mesh net, and two samples of seaweeds with epiphytes by hand from an islet on the barrier reef. In addition, the seaweed-associated diatoms from our 2018 study were analysed using scanning electron microscopy. A total of 109 diatom taxa are documented in the present study. Of these, 70 species were from net samples, and 39 species from the seaweed-associated diatoms. Thirty-one species are newly recorded from Micronesian waters. Most taxa are benthic or tychoplanktonic; euplanktonic diatoms were rare. The occurrence of benthic diatoms from the water column might be related to the Chuuk environmental conditions which include shallow water, strong light intensity and high grazing pressure, to which benthic diatoms seem to be able to better adapt than planktonic diatoms.

Data collections are a hallmark of nineteenth-century administrative knowledge making, and they were by no means confined to Europe. All colonial empires transferred and translated these techniques of serialised and quantified information gathering to their dominions overseas. The colonial situation affected the encounters underlying vital statistics, enquête methods and land surveying. In this paper, two of those data collections will be investigated—a survey on land and a survey on indigenous law, both conducted around 1910 on the Micronesian island of Pohnpei, which had fallen under German colonial influence a decade earlier. Strikingly, there are no enumerators or envoys of the state visiting the doorsteps of Pohnpei. To facilitate the data collection on homesteads, the whole population of the island was called upon to measure their respective plots of land themselves, without resorting to certified land surveyors. The preserved cadastral lists and spreadsheets testify to a rather peculiar contact between the colonizing administration and the colonized peoples. I argue that the production of data made encounters necessary, which are best observed though a methodological focus on data practices. I argue, furthermore, that the Pohnpeians were prompted during the surveys to define their homestead in new terms. This did not only entail new two-dimensional plots but also a new regime of private property. The change in the legal concept can be seen as a continuation of colonial violence by other means, given that it happened in the aftermath of the defeated Pohnpei Rebellion. The argument of the paper is, therefore, that data collection can have formative effects on society, and that measurement and quantified information are often, as Witold Kula argued, a scene of conflict. At its core, the installation of these metric regimes signified a change in patterns of justification, resource management and the unwritten constitution of the Pacific island.

Even though Southeast Asia is one of the most densely populated regions of the world, its rock art is relatively unknown, and the rock art of Micronesia is even less so. As a starting point for comparing Philippine rock art within the region, a systematic quantitative literature review (SQLR) was conducted to assess the current body of accessible publications. The SQLR resulted in 126 viable references, and characteristics of those references were quantified and analyzed to ascertain the qualities of research published to date. The SQLR results show that scholarship in Southeast Asian rock art is increasing and that the research is dominated by Australia-affiliated scholars. It also quantitatively affirmed that the most noted color for rock art in the region is red and the most commonly identified motif is anthropomorphic. Many motifs found elsewhere in Southeast Asia are notably absent in the known corpus of Philippine rock art. Finally, we discuss SQLR methodology and propose integrating collaborative semantic web applications to increase efficiency and relevance.

Pingelap Atoll, 1.8 km2 in area and nearly 70 km from the nearest island, presents a clear example of anthropogenic niche-building in physically isolated circumstances with limited resources. This paper presents the first radiocarbon (14C) dates (n=8) from an archaeological project examining settlement and subsistence practices on the atoll, specifically how Pingelapese people have constructed the environment to meet their needs over centuries of occupation. These dates confirm that human occupation of Pingelap occurred by 1700–1550 cal BP (2σ) at the latest, only a few centuries after the earliest securely-dated settlement of high islands in the region (Kosrae and Pohnpei), and with strikingly similar timing to another atoll in the region, Mwoakilloa. Evidence of early settlement includes shell tools, ornaments, extensive marine faunal remains, and charred botanical domesticates. These preliminary data build a framework for the settlement history and environment building of Pingelap.

Recent excavation at Ucheliungs Cave in Palau has provided new evidence in the debate concerning the colonisation of the Palauan archipelago. An abundance of faunal material and the presence of transported artefacts contradict a previous interpretation that the site represents an early burial cave containing purported small-bodied humans. New radiocarbon dates suggest long-term use of the cave for both mortuary activity and small-scale marine foraging that may slightly precede the accepted date for the earliest human occupation of Palau. The results of this research here discount earlier claims for insular dwarfism among the earliest inhabitants of these islands.

A robust marine radiocarbon (14C) reservoir correction (ΔR) is essential for calibrating 14C dates of marine mollusks and fish bones routinely found in archaeological sites as discarded food remains and bones of terrestrial animals (including humans) with an appreciable marine diet. New ΔR values are reported for the atoll archipelago of the Marshall Islands, eastern Micronesia. Atolls consist of biogenetic material—mostly coral and foraminifera—that can be directly dated for establishing sequences of atoll emergence and islet development. After sectioning and examination using scanning electron microscopy (SEM) to screen for sample diagenesis, 6 pristine branch coral samples were selected from the modern oceanside beach, 3 archaeological sites, and islet developmental facies from Ebon Atoll (4º34′N, 168º41′E). Each sample was analyzed by U-series and accelerator mass spectrometry (AMS) 14C showing no substantial temporal ΔR variations and yielding a weighted mean ΔR of 41±42 yr1 spanning ~500 yr before earliest human colonization (the period when islets first became habitable) through the entire 2000-yr occupation sequence. Reliable published ΔR values for Micronesia and Δ14C data for Palmyra Island, together with our results for Ebon Atoll, indicate that the Pacific North Equatorial Counter Current is almost stable for the past 2500 yr.

The limestone cliff face overlooking the coastline of Ritidian, on Guam, has revealed several caves with evidence of human activities. Since 2011, archaeological survey and excavation have exposed how use of the caves had changed over time, and that they were the focus of special behaviours, with quite distinct archaeology to that of nearby residential sites. To understand the significance of these caves fully, they must be contextualised within the broader framework of contemporary open-air sites. The result highlights the use of the caves for unique purposes at different times, including as water sources, venues for various art traditions and particular burial customs.

Throughout the tropics, developing countries and territories are highly dependent on nearshore marine resources for food and income, however information on the sustainability and proper management of these fisheries is lacking. In Pohnpei, Micronesia, the sustainability of a coral reef finfishery was assessed by comparing coral reef fish demand to coral reef biocapacity using a marine ecological footprint (MEF) analysis. Based on geo-referenced satellite and aerial imagery, Pohnpei and surrounding atolls have 184.2 km2 of coral reef habitat with a sustainable finfish yield of 573–1118 t yr−1, however total harvest was estimated at 4068 t yr−1, exceeding biocapacity by 360–710%. The MEF was supported by observed impacts to coral reef resources, including (1) long-term declines in fish spawning aggregation density, (2) reductions in mean size, age and fecundity of key commercial species, (3) reliance on undersized fish, and (4) decadal declines in mean size and abundance of fishes of iconic value and critical to ecosystem maintenance. The commercial fishery was responsible for 68% of finfish catch volume, while reef fish consumption, at 93 kg person−1 yr−1, was among the highest in the region. To sustainably meet current demand, up to 833 km2 of additional reef area would be required. The study illustrates the MEF, at least rudimentarily, reflects biological reality on local reefs and represents a valuable analytical tool in a marine policymaker's toolbox.

Hormophysa cuneiformis, a brown macroalga in the family Sargassaceae, is now documented from Pohnpei based on a specimen collected in May 1957 and recently discovered in the Herbarium Pacificum of the Bishop Museum. Previously documented collections of H. cuneiformis in Micronesia were made from Palau in the western Pacific in July 1968 and January 1971, and Pagan Island in the Northern Mariana Islands in July 1975.

Calappa karenae, is here documented from Loyalty Islands, Melanesia, based on a specimen collected in September 2011. This rare deep water box crab was previously known only from a pair of specimens collected in off Guam, Micronesia, a distance of 4000 km away.

The first known collections of marine algae from Santa Rosa Reef, a submerged seamount located 46 km south-south-west of Guam in the Mariana Islands, occurred at 10.0 to 13.7 m depths in 2003 and 2005. Dasycladus vermicularis, a green alga known predominantly from the Caribbean but also reported from the Philippines in 1976 and the Ryukyus in 1995, and Cutleria irregularis, a brown alga first described from the Hawaiian Islands in 2003, represent the first record of D. vermicularis in the Polynesia–Micronesia region, and the first record of C. irregularis in Micronesia. In total, 8 of the 32 algal species collected at Santa Rosa Reef represent new records for the Mariana Islands.

A new kinorhynch genus and species is described from coralline sand collected on the atoll of the Chuuk Islands, Micronesia. The new genus and species, Triodontoderes anulap gen. et sp. nov., is characterized by having an introvert with only five scalid rings, segment 1 consisting of one tergal and one sternal plate, segments 2 to 4 of one tergal and two sternal plates, and segments 5 to 11 of one tergal plate with midventral articulation. Triodontoderes anulap gen. et sp. nov. shares several characters with species of Zelinkaderes, including reduced number of scalid rings, distally tripartite placids, a trunk being circular in cross-section, and segments 5 to 10 being composed of a single tergal plate with midventral articulation. Until the kinorhynch relationships have been examined in a formal phylogenetic analysis, Triodontoderes gen. et sp. nov. are tentatively assigned to Zelinkaderidae.

The author reports the oldest human skeletal assemblage found so far in the pacific Islands: at the site of Chalechol Ra Orrak on Palau, Micronesia.