Nearby Islands Research Articles

Characterisation of 'Candidatus Methylobacter titanis' sp. nov., a putative novel species of Methylobacter clade 2 and their distribution in sediments of freshwater lakes in maritime Antarctica.

Global warming has a strong impact on the polar regions, in particular, the Antarctic Peninsula and nearby islands. Methane (CH4) is a major factor in climate change and mitigation of CH4 emissions can be accomplished through microbial oxidation by methanotrophic bacteria. Understanding this biological process is crucial given the shortage of research carried out in this geographical area. The aim of this study was to characterise psychrophilic enrichment cultures of aerobic methanotrophs obtained from lake sediments of the Fildes Peninsula (King George Island, South Shetland Islands) and revealing the distribution of the genus Methylobacter in different lake sediments of the peninsula. Four stable methanotrophic enrichment cultures were obtained and analysed by metagenome-assembled genomes (MAGs). The phylogeny of methanotroph MAGs recovered from these enrichment cultures based on the 16S rRNA gene showed that K-2018 MAG008 and D1-2020 MAG004Ts clustered within the Methylobacter clade 2, with high similarity to Methylobacter tundripaludum SV96T (97.88 and 98.56% respectively). However, the average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values with M. tundripaludum were < 95% (84.8 and 85.0%, respectively) and < 70% (30.2 and 30.3%, respectively), suggesting that they represent a putative novel species for which the name 'Ca. Methylobacter titanis' is proposed. This is the first species of clade 2 of the genus Methylobacter obtained from Antarctica. The bacterial diversity assessed by 16S rRNA gene sequencing of 21 samples of different lakes (water column and sediments) revealed 54 ASVs associated with methanotrophs and the genus Methylobacter as the most abundant. These results suggest that aerobic methanotrophs belonging to the Methylobacter clade 2 would be the main responsible for CH4 oxidation in these sediments.

A taphonomic clock based on the coral grain size of beach sediments from the Yongle Atoll, South China Sea

The grain size characteristics and aging of beach sediments from six islands of the Yongle Atoll, South China Sea, were measured to examine the taphonomic degradation of coral clasts in sediment reservoirs of reef environments. Seventy-one beach sediment samples were collected from 22 transects on 6 islands for sediment characteristic analyses, and 16 bulk sand samples and 28 coral samples were selected for 230Th dating. The mean grain size and ages of coral clasts showed a significant negative correlation (F25 = −0.721, p = 0.01). A grain size age model was established to explain the taphonomic degradation mechanism of coral clasts over time, and an empirical relationship between the mean grain size and 230Th ages was obtained from the Yongle Atoll. The mismatch of the taphonomic clock by grain size data was analyzed, and it was mainly caused by the influence of sorting processes and the intrinsic morphology of coral skeletons that occurred at the early stage of the breakdown process. The application of the model to a nearby atoll island showed that for coral sediments with homogeneous taphonomic conditions, the predicted age was well matched with the measured age. This work presents a general framework for understanding coral clast degradation trajectories with time in taphonomic environments, and it provides a feasible method to predict the coral age independent of other dating methods.

The Adriatic Catholic Marian Pilgrimage in Nin near Zadar as a Maritime Pilgrimage

Following the general approach to pilgrimage as established by anthropologists and other scientists, the paper analyses the pilgrimage in Nin to Our Lady of Zečevo. More specifically, this pilgrimage will be observed as a maritime pilgrimage, following relevant recent research. Based on the oral story about the apparition of Virgin Mary to a widow, the statue of Mary is transported from Nin in a boat procession via sea to a mediaeval church on the nearby uninhabited island of Zečevo. Pilgrimage practices include many sensorial and symbolic practices, so it will be analysed from several points of view and more than one theoretical approach, including the relational approach and mobility turn, applied also to maritime pilgrimage with a reflection on influence of tourism on pilgrimage activities, especially in the Mediterranean. The paper relies on the field research from 2020–2023 in Nin near Zadar in Croatia which has been supported in part by the Croatian Science Foundation under the project ‘PILGRIMAR’ (UIP-2019-04-8226).

Protected fish spawning aggregations as self-replenishing reservoirs for regional recovery.

Dispersal of eggs and larvae from spawning sites is critical to the population dynamics and conservation of marine fishes. For overfished species like critically endangered Nassau grouper (Epinephelus striatus), recovery depends on the fate of eggs spawned at the few remaining aggregation sites. Biophysical models can predict larval dispersal, yet these rely on assumed values of key parameters, such as diffusion and mortality rates, which have historically been difficult or impossible to estimate. We used in situ imaging to record three-dimensional positions of individual eggs and larvae in proximity to oceanographic drifters released into egg plumes from the largest known Nassau grouper spawning aggregation. We then estimated a diffusion-mortality model and applied it to previous years' drifter tracks to evaluate the possibility of retention versus export to nearby sites within 5 days of spawning. Results indicate that larvae were retained locally in 2011 and 2017, with 2011 recruitment being a substantial driver of population recovery on Little Cayman. Export to a nearby island with a depleted population occurred in 2016. After two decades of protection, the population appears to be self-replenishing but also capable of seeding recruitment in the region, supporting calls to incorporate spawning aggregation protections into fisheries management.

Water visitation patterns by Eleonora’s falcon at its breeding grounds: a case study using visual observations and camera traps

Water is a vital resource providing multiple services to many organisms, including birds. Eleonora’s falcon is an iconic, long-distance migrant bird of the Palearctic region. While various aspects of its life history have been thoroughly studied, its dependence on water sources has been poorly documented. In this study, we examine for the first time the species’ visitation patterns at a complex of small, natural ponds of karstic water on a Greek island and provide a detailed description of its bathing and drinking behaviour using visual observations and camera traps. Our results indicate that the species visits the ponds systematically from spring until autumn to bathe and drink. Water visitation patterns suggest communal behaviour, most probably benefitting from increased vigilance in greater numbers. In spring, male falcons prevail during water sessions and the reverse pattern is observed in autumn, whereas morph ratio remains stable, close to the expected 3:1 ratio. Temperature, affecting the falcons’ foraging activity and/or their heat dissipation requirements, together with seasonal differences in labour division between sexes can explain a significant amount of the observed variability in water visitation patterns. Freshwater sources in most islets hosting breeding colonies are scarce, thus natural ponds in nearby larger islands are an important resource many falcons could rely on while at their breeding grounds. The identification and preservation of bathing and drinking spots where falcons gather in numbers across its breeding range is thus highly recommended. Considering the forecasted impact of climate change on karstic water we also encourage an in-depth analysis of the role of water in the adaptation of Eleonora’s falcon to a life in insular environments experiencing global warming. Last but not least, further investigation of the species’ communal behaviour regarding water use can also offer interesting insights in the species’ natural history. HIGHLIGHTS•Eleonora’s falcons visit the water ponds systematically and communally to bathe and drink •Temperature variability and differences in labour division between sexes explain water visitation patterns to a large extent

Current Status of Coral Reef Fish Abundances at Pulau Bidong and Nearby Islands, South China Sea Using Stereo-Diver Operated Video System

Current Status of Coral Reef Fish Abundances at Pulau Bidong and Nearby Islands, South China Sea Using Stereo-Diver Operated Video System

Revisiting HF Ground Wave Propagation Losses Over the Ocean: A Comparison of Long‐Term Observations and Models

[ Understanding variations in the received power levels for land-based high frequency radar systems is critical to advancing radar-based estimates of winds and waves. We use a long-term record of one-way high frequency radar power observations to explore the key factors controlling propagation losses over the ocean. Observed propagation loss was quantified using an 8-month record of radio frequency (RF) power from a shore-based transmitter, received at two locations: an offshore tower and a nearby island. Observations were compared to environmental factors such as wind speed and air temperature as well as models of path loss incorporating smooth and rough surface impedances and varying atmospheric properties. Significant differences in the observations at the two sites existed. One-way path loss variations at the tower, a wavelength above mean sea level, were closely related to atmospheric forcing, while variations at the distant island site were dominated by wind-driven surface gravity wave variability. Seasonal variability in ocean conductivity had no significant effect on over-ocean path losses. Simplistic analytical models of path loss were found to have more skill than either ground wave propagation models or more complex numerical models of field strength in matching the observations, due in part to under-observation of the atmosphere but also the differences in rough surface impedance between models of ocean waves. ]

Animal Resistance in the Global Capitalist Era

Animal Resistance in the Global Capitalist Era

Landslide Induced Tsunami Hazard at Volcanoes: the Case of Santorini

The destructive tsunami on 22 December 2018 due to the flank collapse of the Anak Krakatau volcano was a bitter reminder of large tsunami risks and of the shortcomings of the existing tsunami warning systems for atypical sources (tsunamis generated by non-seismic and complex sources). In the Mediterranean, several tsunamis were generated by landslides associated with volcanic systems in the past.The volcanic unrest experienced in 2011–2012 on the Santorini volcanic island in the Southern Aegean Sea pointed out the need to identify and quantify tsunami hazard and risk due to possible flank instability which may be triggered as a result of volcanic unrest or nearby seismotectonic activities. Inspired from this need, in this study we examined three possible landslide scenarios in Santorini Island with tsunamigenic potential. The results show that the scenarios considered in our study are able to generate significant local tsunamis impacting Santorini and the nearby islands, as well as producing significant impact along the coasts of the Southern Aegean Sea. While maximum tsunami amplitudes/arrival time ranges are 1.2 m/30-90 min for locations in the Greek-Turkish coasts in the far field, they are in the order of ≈60 m/1-2 min for some locations at the Santorini Island. The extreme tsunami amplitudes and short arrival times for locations inside the Santorini Island is a major challenge in terms of tsunami hazard warning and mitigation. As an effort to address this challenge, a discussion on the requirements for local tsunami warning system addressing atypical sources in the context of multi-hazard disaster risk reduction is also provided.

Numerical modeling of a potential landslide-generated tsunami in the southern Strait of Georgia

We report results of numerical simulations of a potential subaerial landslide on the coast of Orcas Island and the resultant tsunami waves in the southern Strait of Georgia near the US/Canada border. A likely trigger is strong ground shaking during large earthquakes on the nearby Holocene active Skipjack Island fault zone. For a worst-case scenario, we assume a 0.17 {textrm{km}}^3 rigid subaerial failure on the steep northeast coast of the island, spanning the sim 5 km between previous landslide deposits on the adjacent seafloor. The landslide motion and resulting tsunami generation are modeled using the three-dimensional (3D) non-hydrostatics physics-based NHWAVE model. The simulated failure moves downslope with a peak velocity of 13.64ṁ/s and travels 732 m before coming to rest after 85 s in 75-m water depth. Tsunami propagation is then continued using the 2D fully nonlinear and dispersive Boussinesq wave model FUNWAVE-TVD in a succession of layered and nested grids. The modeling reveals susceptible locations, particularly as waves will arrive with little or no warning. In the near-source region, modeled waves have peak amplitudes of 15–20 m, current speeds of up to 10 m/s, and runup of up to 30 m. Smaller, but significant, wave amplitudes and runup occur throughout the region surrounding Orcas Island. In the tsunami propagation direction, runup reaches 7.5 m at Neptune Beach near Lummi Bay. Both initial and reflected waves cause significant runup (> 1.5 m) along much of the shoreline between Point Roberts and Lummi Bay.

Necropolitics as accumulation: Enforcement and enclosure in Brisbane during COVID-19

This article explores the uneven impacts that Indigenous and detained migrant populations have endured in Australia in the context of the COVID-19 pandemic. Australia has one of the most restrictive immigration enforcement systems in the world. Along with imposing practices of mandatory detention in rural and remote regions, the Australian government finances the carceral systems of nearby countries and island nations. These logics of enforcement are embedded within histories and techniques of Indigenous quarantine, incarceration, and colonial erasure. Following Achille Mbembe (2019), I advance a theoretical framework of ‘necropolitics as accumulation.’ I argue that rather than disposable or ‘wasted’ populations, those subject to slow violence are within heightened circuits of accumulation. I draw on long-term ethnographic research in Brisbane to emphasize the intensification of governing measures that not only inflict slow death but also make a profit from capitalizing on it. People are kept alive through precarious visa statuses and in prisons, detention centers, camps, remote communities, reserves, and other institutional facilities in relation to their utility for capital, even as death in such spaces is inescapable. In focusing on racial capitalism, I center the differential experiences of Black, Brown, and Indigenous people from COVID-19 in long-standing histories of capitalist exploitation. By attending to the cross-cutting ways in which people are prevented from participating in society, made plain in the pandemic, I call for intersectional advocacy that works towards collective flourishing.

A new species of Phyllurus leaf-tailed gecko (Lacertilia: Carphodactylidae) from Scawfell Island, mid-east Queensland, Australia

A recent targeted reptile survey of Scawfell Island, in the South Cumberland Group, revealed a species of Phyllurus gecko that could not be morphologically assigned to any described species. Here I describe this as a new species, Phyllurus fimbriatus sp. nov., based on differences in a number of morphometric and scalation traits from congeners. Phyllurus fimbriatus sp. nov. is restricted to deeply-piled boulder habitat under rainforest canopy on Scawfell Island, approximately 50 km offshore from Mackay in mid-east Queensland. A survey in rocky, rainforest habitat on nearby Carlisle Island failed to find the species, and other nearby islands appear to lack sufficiently deep rock outcropping to support the species. Phyllurus fimbriatus sp. nov. is known from two small patches of habitat on Scawfell Island, but it is common within these, and is likely to be found in other suitable habitat patches on the island. Based on assessment of imagery, the total area of habitat occupied may be < 1 km2. The island is protected within South Cumberland National Park, but fire encroachment from adjacent dry sclerophyll habitats, climate change, competition from introduced Asian House Geckos (Hemidactylus frenatus Duméril & Bibron, 1836), and poaching are potential threats.

Quantitative morphology and mtDNA reveal that Lasius maltaeus is not endemic to the Maltese Islands (Hymenoptera, Formicidae)

Lasius maltaeus Seifert, 2020 was recently described as a Maltese endemic ant based on quantitative morphology, after decades of uncertainties over the identity of the local population, which has a phenotype resembling L. emarginatus (Olivier, 1791). At the same time, Sicilian L. emarginatus populations were discovered to diverge in their mitochondrial DNA to a degree that suggested heterospecificity. Considering the biogeographic similarity of Malta and Sicily, with land bridges connecting them repeatedly until the last glacial maximum, we questioned the assumption that L. maltaeus was endemic to Malta. We integrated quantitative morphology and mtDNA in the study of the Maltese and southern Italian populations phenotypically close to L. emarginatus. We discovered that the range of L. maltaeus extends over most of Sicily, while the true L. emarginatus replace it in the north-eastern sector of the island, the nearby Aeolian Islands, and the Italian peninsula. The distributions of L. emarginatus and L. maltaeus in Sicily follow biogeographic patterns recalling the island’s complex paleogeographic history. Further investigations should verify the existence of truly Maltese endemic ants, since the status of other allegedly endemic species is not strongly supported.

Notes on the Introduced Small Mammals of Tinian, Mariana Islands1

The negative effects of introduced small mammals have been well documented on islands, but their presence in the Mariana Islands warrants special attention, as they are an important prey species of the introduced brown treesnake (Boiga irregularis), which devastated the avifauna of Guam and remains a threat for introduction to nearby islands. The U.S. Navy has a major presence in the Mariana Islands and is charged with maintaining biosecurity protocols when transporting equipment between islands. We conducted small mammal trapping on Tinian, located approximately 165 km northeast of Guam, in 2017 as a baseline survey of introduced species distribution in areas used for military training. These data will facilitate long-term monitoring of introduced small mammals and early detection of newly established species. We also report an updated Catch Per Unit Effort index of small mammal abundance and tested for differences in capture success across species and between two trap types: Sherman live traps and Victor snap traps. We confirmed general patterns of abundance and distribution from previous sampling on Tinian: Rattus diardii and Suncus murinus were common and widespread, Mus musculus less common and more patchy in distribution, R. norvegicus rare, and R. exulans not detected. Comparisons between Sherman and Victor traps showed important differences in species-specific capture rates on Tinian and aligned with previous research from the Mariana Islands.

Pacific Gulls (Larus pacificus) as Potential Vectors of Coxiella burnetii in an Australian Fur Seal Breeding Colony.

Recently, Coxiella burnetii has been described as a novel pathogen potentially contributing to decreased pup production in Australian fur seals (AusFS, Arctocephalus pusillus doriferus). Pacific gulls (PGs, Larus pacificus) are known to scavenge AusFS placental material during the fur seal breeding season. It is hypothesized that PGs may act as vectors for this pathogen. In the present study, cloacal swabs, oral swabs and serum were collected from PGs on Kanowna Island (KI, an AusFS breeding colony) and a nearby island, Seal Island (SI), not occupied by pinnipeds. All sample sets were evaluated with qPCR for the com1, htpAB and IS1111 markers. Most oral and cloacal swabs from KI tested positive on both the com1 (94.1%; 88.2%) and htpAB targets (76.5%; 76.5%). Amplification was very low from the SI oral swabs and cloacal swabs. Only the KI serum samples had amplification (17.7% for both com1 and htpAB). There was no IS1111 amplification in either colony. The results demonstrate that PGs can potentially act as vectors for the spread of C. burnetii. In some birds, C. burnetii was detectable in the serum, indicating that gulls can experience bacteraemia. It appears that different feeding strategies in the same species within the same ecosystem can have profound effects on the prevalence of pathogens. Further studies are required to better understand the epidemiology and potential risks of this organism.

Post-Tsunami monitoring of the introduced Banggai cardinalfish (Pterapogon kauderni) population in Palu Bay

Post-disaster recovery of marine ecosystems and species is still poorly understood. The Banggai cardinalfish (Pterapogon kauderni) is an ornamental fish endemic to the Banggai Archipelago and a few nearby islands. Classified as Endangered in the IUCN Red List, this fish has limited protected status under Indonesian law. Introduced to several sites in Palu Bay in the early 2000’s, two populations had become established by 2006. Until the triple disaster (earthquake, tsunami, liquefaction) in September 2018, these populations were used for research and education as well as the aquarium trade. The tsunami devastated habitat and microhabitat at the Mamboro site; a census in 2019 found 10 surviving juvenile Banggai cardinalfish in one sea anemone. Monitoring in June 2021 revealed signs of ecosystem recovery, especially seagrass. Despite limited microhabitat with few corals and a lack of Diadema sea urchins, there was a substantial increase in Banggai cardinalfish abundance with all life stages present. New recruits were observed in sea anemones and upside-down jellyfish (Cassiopea sp.). These sites present a natural laboratory for P. kauderni population and post-tsunami ecosystem recovery. Lessons learned can be used to inform conservation management of depleted P. kauderni populations in the endemic range of this endangered fish.

Microbial community and genome structure in coastal seawater from a commercial port and nearby offshore island in northern Taiwan

Microbial community and genome structure in coastal seawater from a commercial port and nearby offshore island in northern Taiwan

How Did Vinh Moc Village, Located near Vietnam DMZ, Protect Their Villagers from United States Air Force Bombardment during the Vietnam War?

The buried village is Vinh Moc where more than 1200 Vietnamese, including soldiers, who lived underground during the Vietnam War (1965 to 1972) were hand dug into red basalt bedrock. The Vinh Moc Village was strategically located on the border of North Vietnam and South Vietnam approximately 14 km north of the DMZ and along the shoreline of the South China Sea. During the Vietnam War, the US Air Force heavily bombed Vinh Moc. The North Vietnamese Army (NVA) had an important military base on nearby Con Co Island. Brave civil volunteers from Vinh Moc would make the 28 km dangerous journey to the island, disguised as fishermen, to deliver supplies to the soldiers stationed there. The people who remained at Vinh Moc dug tunnels into red basalt hills in order to survive this onslaught. The American forces assessed the villagers of Vinh Moc were supplying food and armaments to the NVA garrison on the island of Con Co, which was in turn hindering the American bombers on their way to bomb Hanoi. The US military objective was to force the villagers of Vinh Moc to leave the area. The villagers initially dug the tunnels to a 10 m depth but the American forces designed bombs that burrowed down 10 m before exploding. The soil tunnels were then deepened to 30 m to provide safety for the soldiers and civilians working there during the intense US Air Force bombing. The primary objective of the research study was to determine how the soils and parent material of Vinh Moc Village, protected their villagers from the United States Air Force bombardment during the Vietnam War. In addition, the natural parent material at both the Vinh Moc and Cu Chi were assessed to determine why the tunnels were so resilient. The Cu Chi and Iron Triangle soil tunnels were dug by hand in the Old Alluvium soils and parent material where iron in solution precipitated and became the soil binding material. The Vinh Moc tunnels were hand dug in porous, red basalt (bedrock) hills where the consolidated rock structure itself provided the required binding material. Neither site needed support beams to hold up the ceilings.

Mycenaean Type Archaic G 2-3 Alabastra from Tenedos

Bu çalışma, Tenedos mezarlarında ele geçen iki alabastronu konu alır. Alabastronlar, morfolojileri bakımından Geç Tunç Çağı Miken alabastronlarına benzerken üzerlerindeki yatay bant süslemeleri MÖ 7. yüzyıl G 2-3 seramiklerindeki kompozisyonlar ile uyumludur. Teneodos’ta bulundukları mezarların kontekstleri çerçevesinde tarihlenemeyen bu kaplar, daha önce Hephaestia’dan (Lemnos) yayınlanan benzerleriyle karşılaştırılarak MÖ 7. yüzyılın ikinci yarısı ve MÖ 6. yüzyılın başlarına tarihlenebilir. Makaleye konu alabastronlar Kuzey ve Doğu Ege kültürel etkileşim ağında üretilen bölgesel seramik kaplarına yenilerini eklerken MÖ 7. yüzyılda revaçta olan Korinth ürünleri yanında bölgesel G 2-3 üslubunda süslenmiş fakat morfolojik açıdan eski modaların devamlılığını yansıtan melez kapların da Tenedos ölü gömme ritüellerine dahil edildiğini gösterir. Bu yönüyle bu alabastronlar Arkaik Dönem’de çağdaş seramik modalarıyla birlikte eski modaların devamlılığının Kuzey Ege’de Lemnos dışında Tenedos’ta da varlığını temsil eder.

Nearby large islands diminish biodiversity of the focal island by a negative target effect.

The Equilibrium Theory of Island Biogeography postulates that larger and closer islands support higher biodiversity through the dynamic balance of colonization and extinction processes. The negative diversity-isolation (i.e. the distance to the mainland) relationship is derived based on the assumption that the mainland is the only source pool for island biotas. However, nearby islands could also act as species sources for focal islands via a source effect. In this study, we move a further step and hypothesize that nearby islands may reduce bird colonizers of the focal island and diminish its biodiversity, resulting in a negative target effect. To test our hypothesis, we assessed the effects of island area and isolation (metrics considering both the mainland and nearby islands) on taxonomic (i.e. species richness), functional and phylogenetic diversity of terrestrial breeding birds on 42 islands in the largest archipelago of China, the Zhoushan Archipelago. Furthermore, we compared the predictive power of the distance to the large island under a set of relative area thresholds and the relative area of nearby islands on species richness under a set of distance thresholds to explore the role of nearby islands as a source and/or target island. We found that island area had a positive effect on species richness, phylogenetic diversity and functional diversity, while the distance to the mainland had a negative effect only on species richness. Species richness on the focal island increased with increasing distance to the nearest larger island, indicating the negative target effect. Furthermore, the negative target effect depended on the area of nearby islands relative to the area of the focal island. Our finding of the negative target effect suggests islands located between the mainland and the focal island can be not only sources or stepping stones, but also colonization targets. This result demonstrates the importance of considering multiple geographical attributes of islands in island biogeographic studies, especially the characteristics related to source and/or target effects.