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Eastern Indonesia's tectonic setting is well known for its complexity and intense seismic activity. Controlled by several major and minor plates, including the Eurasian, Australian, and Pacific plates, this region is famous for its U-shaped subduction system beneath the Banda Arc. To better understand the architecture of the underlying structure in this region, we performed body-wave travel time tomography using ten years of catalog data provided by the Indonesian Agency for Meteorology, Climatology, and Geophysics. We utilize 9729 events in total, from which 46,446 P-wave arrival times were extracted. We used a double difference method to relocate the initial event catalog, which produced a pattern of seismicity consistent with a curved subduction system. Our tomographic model reveals a high velocity band between 90 and 240 km depth in the upper mantle, which is interpreted to be a concave dipping lithospheric slab that is parallel to the present-day Banda arc. Our results also show that lithosphere subducting from the north and south starts to collide at a depth of 300–350 km and becomes shallower further east. Apparent discontinuities in the high velocity band and a corresponding lack of seismicity supports the presence of a slab tear to the west of Seram. A dipping high velocity structure that is present from south to north beneath the island of Timor represents a subducting slab that dips more steeply beyond a depth of 150–200 km, which appears consistent with slab roll-back. Our tomographic model also shows evidence of back arc thrusting to the north of Sumbawa and Flores Islands in the form of a south-dipping higher velocity band at shallow depth. Furthermore, our tomographic models also reveal the possible presence of underthrust continental forearc in the form of a thin higher velocity anomaly that connects the backarc thrust and northward dipping lithosphere slab in the Timor area. Finally, a zone of low velocity above the higher velocity slab is clearly seen beneath Seram Island at a depth of ∼100 km and may represent a partial melting zone. [Display omitted] • We present a high-resolution seismic tomography study of the upper mantle beneath Eastern Indonesia, revealing detailed velocity structures down to depths of 400 km. • Our findings provide new insights into the subduction dynamics beneath the complex tectonic regime of Eastern Indonesia, including the presence of multiple subduction zones and their interactions. Our models also support previous proposed model in this region. • We characterize the morphology and dynamics of subducted slabs, highlighting variations in slab dip angles and mantle flow patterns, which influence regional seismicity, partial melting process and volcanic activity. • The detailed imaging of seismic velocity anomalies may aid in seismic hazard assessment by delineating potential earthquake rupture zones and identifying regions of heightened seismic risk. [ABSTRACT FROM AUTHOR]

The plate boundary between the Pacific-Caroline and Australian plates in northwestern New Guinea is associated with a geographic concentration of earthquakes developed in the Ransiki region of the northeastern Bird's Head Peninsula (West Papua, northwestern New Guinea) at the intersection of the Ransiki and Yapen faults. We examine these earthquakes based on regional geomorphological and lithostratigraphical frameworks, field observations of surface ruptures and liquefaction phenomena, and focal mechanisms of historical earthquakes. The Ransiki earthquakes are a set of 29 earthquakes from the Global Centroid Moment Tensor catalogue in the period 1977–2019 (magnitudes of Mw4.9 to Mw7.5). In the east, focal mechanisms show sinistral movement along the east-west trending Yapen Fault including the Mw6.7 earthquake on 21 April 2012. The largest earthquake was on 10 October 2002 (Mw7.5) and along with other earthquakes mainly in the southwest were associated with dextral movement indicated by focal mechanism solutions on the northwest trending Ransiki Fault south of its intersection with the Yapen Fault. The southern part of the Ransiki Fault therefore indicates local north-northeast compression that is also evident in the newly recognised Wainoei Fault south of Yapen Island. The two largest earthquakes (10 October 2002, 21 April 2012) show ground effects associated with liquefaction, indicated by surface offsets, open fissures, and sand blows, that all occurred in saturated sediments of the Ransiki delta. Earthquakes in the Ransiki region show that west-southwest oblique plate convergence between the Australian and Pacific-Caroline plates is partitioned into east-west sinistral strike-slip motion along the Yapen Fault and north-northeast compression associated with the Ransiki Fault. [Display omitted] • Earthquakes are located at a fault intersection near the Pacific plate boundary. • Oblique-slip plate motion is partitioned into strike-slip and convergent parts. • Focal mechanism solutions indicate both sinistral and dextral movements. • Earthquake damage is mainly controlled by liquefaction in a Quaternary delta. [ABSTRACT FROM AUTHOR]

This paper examines the development and effects of a rapid livelihood transition on households, and reflects on how it fits within historic trends of livelihood change for people living in highly variable and vulnerable environments. It also discusses the implications of livelihood dynamism for local governance of natural resources. In recent decades, seaweed cultivation has expanded exponentially in coastal communities across the Asia-Pacific. A case study is presented of a remote small-island community in eastern Indonesia where over the last ten years a dramatic shift in livelihood focus has occurred. Previous dependence on diverse low-productivity livelihood activities transitioned to a predominant focus on seaweed farming. The case shows how social, economic and cultural environments co-develop as people move out of conditions of collective poverty and into more nuclear household-oriented livelihood activities. Specific attention is given to the influence on a marine resource co-management program operating on the island to illustrate how local livelihood dynamics relate to broader paradigm-driven conservation and rural development initiatives. While alternative livelihood programs seek to relieve pressure on resource stocks and provide opportunities for coastal people, this case study provides timely insights into the kinds of unintended effects, trends and impacts that are associated with rapid change in the way people make a living. This study argues that, in addition to achieving higher standards of income and well-being, livelihood improvement interventions need to adequately ensure that conditions under which new livelihood arrangements come to function can be maintained locally. [ABSTRACT FROM AUTHOR]

The 190-km-long Matano fault is a major left-lateral strike-slip fault in Sulawesi, Indonesia that accommodates the rapid westward motion of the Pacific plate relative to the Australian plate. The Matano fault has remained unruptured at least in the past two centuries. The lack of geologic information, such as precise active fault traces, paleoseismic history, and slip rates has been a significant barrier to assessing the seismic hazards of the Matano fault. This paper presents the results of tectonic geomorphic and paleoseismic investigations on the 30 km long easternmost portion of the Matano fault. We identified four geometrical fault segments, documented five surface faulting events, and calculated a surface-rupturing earthquake recurrence interval of 200–470 years and a slip rate of 21 ± 9 mm/yr. The timing of the most recent surface-rupturing earthquake was constrained between 1432 and 1819 CE with an estimated M w ∼ 7.4 and a probable rupture length of ∼110 km. At least 200 years have passed since the latest faulting event, exceeding the shortest recurrence interval. Thus, the next surface-rupturing earthquake is already due. Integrating our interpretations with results from several published studies clarifies that the Matano fault slips slower than the Palu-Koro fault and connects to the South Sula fault in addition to the Tolo thrust. • The Matano fault is characterized by a complex fault segmentation at its easternmost part. • The first paleoseismic investigation on the Matano fault documents five paleoseismic events. • The last surface faulting event on the easternmost Matano fault was dated between 1432 and 1819 CE with an estimated M w ∼ 7.4. • The easternmost Matano fault exhibits a large earthquake recurrence interval of 200–470 years and a slip rate of 21 ± 9 mm/yr. [ABSTRACT FROM AUTHOR]

Classical swine fever has been negatively impacting pig production in Nusa Tenggara Timur province in eastern Indonesia since its introduction in the 1990s, with live market trade contributing to disease spread. To understand market trader knowledge and practices regarding pig management, biosecurity, pig movements and pig health (specifically CSF), a repeated survey was conducted with pig sellers and pig buyers at 9 market sites across West Timor and the islands of Flores and Sumba. A total of 292 sellers and 281 buyers were interviewed in 2009 during two periods (rounds), a high-demand month (September) and a low-demand month (November). Information was collected via questionnaire. The majority of traders were male (sellers: 89%; buyers: 87%) with the highest level of completed education being primary school (sellers: 48%; buyers: 41%). The primary occupation of most respondents was farming: 90% of sellers and 87% of buyers were smallholder pig farmers and tended to sell their own home-raised pigs at market (52%). Pigs were sold for monetary gain either for primary (52%) or extra income (44%). Markets tended to be selected based on a good reputation (62%), a location close to residence (62%) and having the desired pig type (59%). Pig sales through markets were reported to be highest from August to October with 31% of sellers trading pigs at two or more markets. Prices at market were significantly higher on Sumba compared to West Timor and cross-bred pigs were significantly more expensive than indigenous pigs. Understanding of CSF and biosecurity was limited: 85% of sellers and 83% of buyers had no prior knowledge of CSF. Fifty-four percent of sellers reported no use of any biosecurity practices at market. Most respondents (88%) were able to recognise at least one clinical sign of a sick pig. Informal pig movements were also identified: 18% of pig buyers purchased pigs directly from other farmers. This study has provided baseline information on market trader activities at live pig markets in NTT that can contribute to the formation of sustainable strategies for improving pig health. Since NTT is the poorest province in Indonesia and pigs play a vital socioeconomic role in this province, market management and farmer education is needed to improve the pig market chain and contribute to socioeconomic development. [ABSTRACT FROM AUTHOR]

Knowledge of live animal movement through markets and from farm-to-farm is needed to inform strategies for control of trans-boundary animal diseases (TADs) in south-east Asia, particularly due to consumer preference for fresh meat. In eastern Indonesia a TAD of principal interest for control is classical swine fever (CSF) due to its impacts on smallholder farmers. Pig movement is considered a contributor to failure of current CSF control efforts but pig movement patterns are not well understood. This study investigated movement of live pigs in West Timor, Flores and Sumba islands during 2009–2010, with the aim of informing CSF control policies for Nusa Tenggara Timor province. A market survey of 292 pig sellers and 281 pig buyers across nine live pig markets and a farmer survey across 18 villages with 289 smallholder farmers were conducted and information collected on pig movements. The data obtained was used for social network analysis (SNA) on formal (via a market) and informal (village-to-village) movements using information on trading practices, source and destination locations, and the number of pigs being moved. Both inter- and intra-island movements were identified, however inter-island movement was only observed between Flores and Sumba islands. West Timor and Sumba had highly connected networks where large numbers of villages were directly and indirectly linked through pig movement. Further for West Timor, both formal and informal pig movements linked the capital Kupang, on the eastern end of the island to the western districts bordering East Timor connecting all five districts and demonstrating that informal movement transports pigs over distances similar to formal movement on this island. Sumba had a higher potential for pigs to move to a greater number of sequential locations across the entire island. Flores was found to have a more fragmented network, with pig movements concentrated in its eastern or western regions, influenced by terrain. Markets were confirmed as high-risk locations for the introduction and spread of disease, having over 20 contacts (based on in- and out-degree values) depending on operational day. Villages considered high-risk for CSF spread via informal movements were characterised by higher volume of pig exits and/or linkage to higher numbers of other villages. These findings demonstrate that informal movement (often related to cultural practices) can be extensive and the high level of connectivity dictates that control strategies for CSF and other highly transmissible diseases must be formulated at the provincial level and in collaboration with East Timor. [ABSTRACT FROM AUTHOR]

Pig farming is a common practice among smallholder farmers in Nusa Tenggara Timur province (NTT), eastern Indonesia. To understand their production systems a survey of smallholder pig farmers was conducted. Eighteen villages were randomly selected across West Timor, Flores and Sumba islands, and 289 pig farmers were interviewed. Information on pig management, biosecurity practices, pig movements and knowledge of pig health and disease, specifically classical swine fever was collected. The mean number of pigs per herd was 5.0 (not including piglets), and total marketable herd size (pigs ≥ two months of age) did not differ significantly between islands ( P = 0.215). Chickens (71%) and dogs (62%) were the most commonly kept animal species in addition to pigs. Pigs were mainly kept as a secondary income source (69%) and 83% of farmers owned at least one sow. Seventy-four percent (74%) of pigs were housed in a kandang (small bamboo pen) and 25% were tethered. Pig feeds were primarily locally sourced agricultural products (93%). The majority of farmers had no knowledge of classical swine fever (91%) and biosecurity practices were minimal. Forty-five percent (45%) reported to consuming a pig when it died and 74% failed to report cases of sick or dead pigs to appropriate authorities. Sixty-five percent (65%) of farmers reported that a veterinarian or animal health worker had never visited their village. Backyard slaughter was common practice (55%), with meat mainly used for home consumption (89%). Most (73%) farmers purchased pigs in order to raise the animal on their farm with 36% purchasing at least one pig within the last year. Predominantly fattener pigs (34%) were given as gifts for celebratory events, most commonly for funerals (32%), traditional ceremonies (27%) and marriages (10%). For improved productivity of this traditional low-input system, research incorporating farming training and improved knowledge on pig disease and biosecurity needs to be integrated with greater access to extension services. [ABSTRACT FROM AUTHOR]

Abstract: Objective: to describe the system of health reporting by village midwives and two rural clinics in eastern Indonesia and solve some of the problems in this system through consultation. Design: participatory action research model where problems are identified by those most affected and solutions sought. Clinic staff were observed and interviewed regarding their work roles and reporting duties. Allocation of work time to various tasks was recorded by all clinic staff before and after the implementation of a new health recording system. Several information sessions and focus group discussions were held with village midwives and other health staff to identify and address problems. Setting: Indonesia initiated a programme in 1989, aiming to place a midwife in every village, in response to high maternal mortality rates and low rates of births attended by trained birth assistants. Remote rural villages in eastern Indonesia have difficulty recruiting and retaining village midwives. These midwives play a crucial role in health reporting. During 2010 a new system of recording and reporting by clinics was implemented. Participants: village and clinic health staff in two rural subdistricts in eastern Indonesia. Findings: there was incomplete coverage by village midwives in the two subdistricts studied; 28% of villages had a resident midwife, 48% had a visiting midwife and 24% had only monthly visits by a mobile clinic. Village midwives performed duties additional to their official duties and training. Village midwives had problems associated with the reporting system including inconsistency in reporting, poor access to individual patient histories and poor access to clinics. These problems resulted in incompleteness and poor timeliness of data transfer. Key conclusions: midwives in remote villages felt compelled to provide services for which they were not trained. Poor quality of data reporting resulted from inconsistent reporting methods. Local staff can successfully change and manage reporting systems if given appropriate support and training. Implications for practice: socialisation of health reporting systems among all staff involved can lead to improved data consistency and completeness. Effective systems for data transfer and reporting may reduce time spent on these tasks by some staff. Improvements to accuracy of data and availability of individual patient histories have the potential to contribute to improved health care. Quality of health care by village midwives should be addressed by adequate training and improved transport. [Copyright &y& Elsevier]

Eastern Indonesia, most notably Nusa Tenggara Timor province, has been frequently referred to as the poorest region in Indonesia and claims have recently been made that it is the most corrupt as well. The spread of corruption in the post-Suharto period, with the introduction of regional autonomy and decentralisation, has often been commented on; but what is corruption? How do people define it? This paper uses an anthropological lens on corruption to suggest that with the spread of ideas of 'good governance' and 'democracy', one significant way that local communities in NTT province engage with the state and define corruption is as an abuse of power and non-consultation with the populace. This has become particularly acute with the government belief that new investment opportunities in the reform era will become a road to development and prosperity for local communities, who are, however, seen to be unable to provide for themselves or seek their own ways out of poverty. Several regional governments in NTT province have taken advantage of new laws put into effect in the reform era to award mining concessions to domestic and foreign mining companies. A swell of protest has arisen across the province, however, and an increasing critique of poor government and corrupt practices focuses on these mining contracts. [ABSTRACT FROM AUTHOR]

The boundaries of what has constituted 'Eastern Indonesia' have shifted depending on the historical, cultural, political, or economic context. We review various ways that Eastern Indonesia has been understood, to overview the different ways of delineating and approaching this fascinating part of Indonesia in order to introduce this special issue. The intention of this special issue, however, is not to attempt to clearly define Eastern Indonesia once and for all, but to open up via these various historical and contemporary concerns with Eastern Indonesia, new ways of grappling with this region in the present Post-Suharto era. The current social and political transformations offer a great deal of opportunity to reflect on the way global and national flows of people, money, notions of governance and religious ideas, are so crucial to understanding and making sense of the current dynamics in the region. By focusing our attention on how these global and national influences intersect with the local, we want to bring out how they are appropriated and manipulated by local communities; at the same time they may undermine and transform what is taking place at the local level. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents an internally and globally consistent model of plate evolution in eastern Indonesia from Middle Miocene to Present time. It is centered on the Banda Sea region located in the triple junction area between the Pacific–Philippine, Australia and South–East Asia plates. The geological and geophysical data available from Indonesia were until recently insufficient to define a unique plate tectonic model. In this paper, the new data taken into account clearly restrict the possible interpretations. Owing to a great number of geological, geophysical and geochemical studies, the major plate boundaries (the Sunda–Banda subduction zone to the south, the Tarera–Aiduna Fault zone and the Seram Thrust to the east, and the Sorong Fault zone and Molucca Sea collision zone to the north) are now clearly identified. The age of the major tectonic structures is also better known. Geodetic measurements well constrain the Present time plate kinematics. We also consider the deformation history within eastern Indonesia, where numerous short-lived microplates and their related microcontinents successively accreted to the Asiatic margin. Moreover, magnetic anomalies identification of the North and South Banda Sea basins allows a precise kinematic reconstruction of the back-arc opening. We used the Plates software to test the coherency of our model, presented as a series of 4 plate reconstruction maps from 13 Ma to the present. Finally, the origin of oceanic domains restored by our reconstruction is discussed. [Copyright &y& Elsevier]

This paper is a study of stakeholders' perceptions of the reliability of landings data obtained by governments on fish stocks. The case studied is the tuna fishery in Indonesia, which is the country's most important fisheries sector in terms of income and employment, but poses particular difficulties for landings data collection because Indonesia is an archipelago made up of 17,500 islands making data collection a very complex, time-consuming, and costly process because of the large number of ports and the need to employ a considerable team of enumerators to collect the data. This study is not an enquiry into whether the officially recorded data are reliable, but whether fishers and other stakeholders believe them to be reliable. We carried out a survey of 921 respondents (724 tuna fishers; 154 live-bait fishers; 16 policy makers; 16 public sectors and 11 private sectors) to investigate their perceptions of the way landings data on tuna are obtained and collated by Indonesian government officials. The results indicate there is considerable scepticism about the accuracy of these fisheries data. Respondents said there was inadequate funding for data collection; the enumerators were poorly trained; and there were few incentives for checking the results of surveys. These and other criticisms raise serious doubts about the efficacy of the management of the tuna fisheries in Indonesia. Stakeholders' perceptions on how to improve their confidence in the data collected include greater involvement of individual fishers and the private sector. [ABSTRACT FROM AUTHOR]

• We examine the oceanographic biophysical conditions at traditional anchored fish aggregating device in eastern Indonesia. • Catch-per-unit relationship with biophysical conditions were analysed with correlation and GAM analyses. • Tuna pole-and-line fishery at the research sites heavily depends on the installations of traditional anchored fish aggregating devices, called rumpon. The research was conducted to investigate the oceanographic characteristics at three traditional anchored Fish Aggregating Device (FADs) sites for tuna pole-and-line fishery in eastern Indonesia. The FADs locations, and sea surface temperature (SST) and chlorophyll-a (chl-a), salinity (sal), wave height (wav), wind (win) current (cur) were examined using a geographic information system (GIS). Relationships between Catch-per-Trip (CPT) with oceanographic characteristics (SST, chl-a, sal, wav, win and cur), were analysed using correlation and generalised additive models (GAMs) analyses. Correlation analyses was used in order to determine how strongly pairs of variables were related to one another, and generalised additive models (GAMs) were used in order to model relationships between Catch-per-Trip (response variable) and the oceanographic variables SST, chl-a, sal, wav, win and cur (predictor variables). Correlation analyses showed that significantly negative correlations were found in entire locations between SST and chl-a while in contrarily, the lowest correlation was found between CPT and chl-a. Furthermore, the GAM plots indicated that a positive association was observed between catch-per-trip and SST with approximately >26.5 °C, chl-a was <0,4 mg/m3, salinity was observed between>33 to < 34.5 (psu) for entire sites while wav was found at>0.23 for Sorong and >0,87 (m) in Larantuka and <0.64 in Pulau Bacan. Win variable had positive effects at>4.1 m/s in entire research sites while cur had a positive effect on CPT occurred at <56 (m/s) for entire locations. The GAM models showed that SST explains up to 20 % whereas chl-a explains as the lowest variable (up to 0.78 % of the deviances) in skipjack CPT relationships, and the addition of predictor variables resulted in an increase in the deviance explained. This research provides evidence that skipjack tuna CPT has relationship with oceanographic variables in eastern Indonesia. [ABSTRACT FROM AUTHOR]

• Acoelomate flatworms specimens are mostly found on host cnidarians. • Acoelomate flatworms specimens include two groups based on external morphology (obcordate, molar-like). • Two morphological groups form well supported phylogenetic clades. • The genus Waminoa is represented by obcordate specimens. • Molar-like specimens constitute potentially an undescribed genus. The genus Waminoa currently contains two described species, which each contains two types of endosymbiotic algae. Waminoa individuals are basically brown in body color, derived from these algal symbionts, and their body shape has been described as "discoid to obcordate". They have been found as associates of various anthozoans (Cnidaria) in the Indo-Pacific Ocean and the Red Sea. In order to reveal the diversity of the genus Waminoa and their hosts, we conducted phylogenetic and morphological analyses on acoelomate flatworms specimens collected from Japan, Palau and Indonesia. At least 18 Waminoa morphotypes were found on at least 20 anthozoan host species, and two specimens were found on species of two sea stars. Overall, there were two main body shapes of specimens; obcordate, as seen in W. litus and W. brickneri , and the other molar-like with an elongated body. These two body shapes each represented a separate clade in 18S rDNA and mitochondrial cytochrome c oxidase subunit 1 (COI) phylogenetic trees, with W. brickneri included in the obcordate subclade. Automatic Barcode Gap Discovery (ABGD) analyses on COI sequences of our specimens revealed the presence of at least five operational taxonomic units (OTUs). These five OTUs consisted of one large group of all obcordate animals, three OTUs consisting of one specimen each within the molar-like clade, and one large group of the remaining molar-like specimens. Both clades contain numerous morphotypes and were associated with a variety of hosts. Finally, based on genetic distances, the molar-like specimens are considered as an unnamed genus group separate from Waminoa , which needs to be clarified in future studies. [ABSTRACT FROM AUTHOR]