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Temporal patterns of oceanic predators can provide valuable information on both lunar and diel influences not just on the distributions of these predators, but also on prey patches that are often difficult to study. Mid-oceanic island chains in the northern Indian Ocean have high odontocete occurrence, but the ecology of these animals is not well characterized. We investigated fine-scale spatial and temporal patterns of island-associated odontocetes using passive acoustic monitoring from January 2019 to January 2020 around Kavaratti Island, Lakshadweep, India. Based on opportunistic recordings in the presence of odontocetes, the majority of the detected whistles were likely made by spinner dolphins Stenella longirostris. We identified a resident population whose whistle occurrence was significantly influenced by month, site, and diel and lunar cycles. More acoustic detections were made in the northeast monsoon month of November and fewer during pre-monsoon and southwest monsoon periods. Distinct day-night differences along with fine-scale temporal variability were also observed, suggesting that delphinids use nearshore waters as a daytime resting habitat. Odontocete detections were highest during the new moon period and lowest during the first quarter phase. Detection rates were higher on the south side of the island. Our study shows that solar and lunar cycles modulate odontocete vocal occurrence, presumably through influences on their prey. Similarities of odontocete occurrence around Lakshadweep to other mid-oceanic island chains suggests that an island-associated micronekton community may exist around Lakshadweep that may also be important to other pelagic species targeted by local fisheries.

The relationship between the Indian Ocean dipole (IOD) and the South Asian summer monsoon (SASM), which remains a subject of controversy, was investigated using data analyses and numerical experiments. We categorized IOD events according to their sea surface temperature anomaly (SSTA) pattern: type W and type E are associated with stronger SSTA amplitudes in the western and eastern poles of the IOD, respectively, while type C has comparable SSTA amplitudes in both poles during boreal autumn. Type W is associated with a weak SASM from May to summer, which contributes to substantial warming of the western pole in autumn; the east–west SST gradient linked to the warming of the western pole causes weak southeasterly wind anomalies off Sumatra and feeble and cold SSTAs in the eastern pole during the mature phase. Type E is associated with a strong SASM and feeble warming of the western pole; interaction between the strong SASM and cold SSTAs in the eastern pole in summer results in strong southeasterly wind anomalies off Sumatra and substantial cooling of the eastern pole during the mature phase. For type C, warming of the western pole and cooling of the eastern pole develop synchronously without apparent SASM anomalies and reach comparable intensities during the mature phase. Observations and numerical simulation results both indicate the role of disparate SASM anomalies in modulating SSTA patterns during the development of positive IODs. Warming of the tropical Indian Ocean becomes established in the winter and spring following type W and type C IODs but not following type E events.

The dodo (Raphus cucullatus) was a large, flightless pigeon endemic to the island of Mauritius (Indian Ocean). Its unusual appearance was recorded in several 17th-century depictions of live or recently killed birds. It became extinct at the end of the 17th century, and in some subsequent accounts, it was even considered as non-existent. Dodo images became rare from the mid-17th century, but its inclusion in Lewis Carroll’s Alice’s Adventures in Wonderland initiated a change, establishing it as an icon to a much wider public. Since then, illustrations of dodos have been used in all kinds of media, arguably making it the most iconic extinct bird. Here we analyse how the dodo image evolved from 1600 to 2013, using 2D-geometric morphometrics. Our results show that in particular cartoons, animations and logos tend to put an extreme emphasis on the bulging anterior part of the beak, and that the beak is strongly hooked. The variation in dodo images has increased since 1865, culminating in an explosion of shapes during the past decades. The often exaggerated, cartoonesque depiction of the dodo is in line with the long-held but incorrect popular belief that it was a clumsy, tragic bird destined for extinction.

The Indian Ocean has a complex geological history that has drawn the attention of naturalists for almost a century now. Due to its tectonic history, many geological elements and processes have been evoked to explain the exchange of species between landmasses. Here, we revisited previous studies on twenty-three taxa to investigate trends across time since the Gondwana breakup. We investigated these datasets by applying a time-calibrated Bayesian framework to them and reconstructing their ancestral ranges. We conclude that ecological transformations have presented opportunities for the establishment of migrants. The role of donating and receiving migrants has shifted several times according to these transformations. Time-specific trends show weak evidence for the stepping-stones commonly suggested as physical routes between landmasses. However, before its collision with Asia, India may have served as an intermediary for such exchanges.

Ceramics have been extensively imported on the East African Coast over many centuries. The principal sources have been Iran and China, the latter trans-shipped through the port of Malacca and the Indian ports of the western Indian Ocean. These ceramics were used to embellish the gates and mihrabs of mosques, and the exteriors of elaborate tombs. They were vessels in homes and decorations on buildings. In the last two centuries, the old ceramics came to be supplanted by imported ware more utilitarian in make and appearance. These came in mainly from Holland, England and Germany. These products of Western Europe were influenced by the Islamic markets they had entered, while in turn these plates became an important part of the East African Coast’s architecture and Swahili traditions and homes.

This article invites readers to rethink the work that routes can do in world history by braiding together the spatial and historical imaginaries of an itinerant community: the dhow captains (nakhodas) of Kuwait. Through a close reading of two genres of nakhoda writings, logbooks and nautical manuals, it explores the deliberate process by which they constructed their movement across the sea. It suggests that for dhows, travel across the Indian Ocean was a voyage through world history itself—a route along a recent and distant past, entangled with an imperial present. Through these materials historians can move towards a sense of space and time that foregrounds the imaginative processes that produce the Indian Ocean as an historical arena on the part of those who spent their lives traversing it.

Extremely anomalous features of Meiyu in 2020 over the Yangtze–Huai River basin (YHRB) and associated causes in perspective of the large-scale circulation are investigated in this study, based on the Meiyu operational monitoring information and daily data of precipitation, global atmospheric reanalysis, and sea surface temperature (SST). The main results are as follows. (1) The 2020 YHRB Meiyu exhibits extremely anomalous characteristics, which are the most prominent since the 1980s. The 2020 Meiyu season features the fourth earliest onset, the third latest retreat, the longest duration, the maximum Meiyu rainfall, the strongest mean rainfall intensity, and the maximum number of stations/days with rainstorm. (2) The extremely long duration of the 2020 Meiyu season lies in the farily early onset and late retreat of Meiyu in this particular year. The early onset of Meiyu is due to the earlier-than-normal first northward shift and migration of the key influential systems including the northwestern Pacific subtropical high (NWPSH) and the South Asian high (SAH) along with the East Asian summer monsoon, induced by weak cold air activities from late May to early mid-June. However, the extremely late retreat of Meiyu is because of later-than-normal second northward shift of the associated large-scale circulation systems accompanied with strong cold air activities, and extremely weak and southward located ITCZ over Northwest Pacific in July. (3) The extremely more than normal Meiyu rainfall is represented by its long duration and strong rainfall intensity. The latter is likely attributed to extreme anomalies of water vapor convergence and vertical ascending motion over the YHRB, resulting from the compound effects of the westward extended and enlarged NWPSH, the eastward extended and expanded SAH, and the strong water vapor transport associated with the low-level southerly wind. The extremely warm SST in the tropical Indian Ocean seems to be the key factor to induce the above-mentioned anomalous large-scale circulations. The results from this study serve to improve understanding of formation mechanisms of the extreme Meiyu in China and may help forecasters to extract useful large-scale circulation features from numerical model products to improve medium-extended-range operational forecasts.

The genus Petta Malmgren, 1866 is a small and poorly known genus of the annelid family Pectinariidae Quatrefages, 1866. A previous revision of the genus found that the type material of the species P. assimilis McIntosh, 1885 had been lost. While searching for material from the type locality, we were able to examine material from a similar area but collected in much shallower water from off South Africa which represents another undescribed species of Petta. The new species, Petta brevissp. nov., is described and compared to P. assimilis McIntosh, 1885, and a revised key to all species in the genus is provided.

As an important part of the Indo-Pacific warm pool, the Indian Ocean has great significance for research on the Asian monsoon system and global climate change. From the 1960s onward, several international and regional programs have led to important new insights into the Indian Ocean. The eastern Tropical Indian Ocean Observation Network (TIOON) was established in 2010. The TIOON consists of two parts: large-scope observations and moored measurements. Large-scope observations are performed by the eastern Tropical Indian Ocean Comprehensive Experiment Cruise (TIO-CEC). Moored measurements are executed by the TIOON mooring array and the hydrological meteorological buoy. By 2019, 10 successful TIO-CEC voyages had been accomplished, making this mission the most comprehensive scientific investigation in China. The TIO-CEC voyages have collected temperature/salinity profiles, GPS radiosonde profiles, and other observations in the Indian Ocean. To supplement the existing buoy array in the Indian Ocean, an enhanced TIOON mooring array consisting of eight subthermocline acoustic Doppler current profiler (ADCP) moorings, was established since 2013. The TIOON mooring equipped with both upward-looking and downward-looking WHLS75K ADCP provide valuable current monitoring information to depth of 1,000 m in the Indian Ocean. To improve air–sea interaction monitoring, two real-time hydrological–meteorological buoys were deployed in 2019 and 2020 in the equatorial Indian Ocean. A better understanding of the Indian Ocean requires continuous and long-term observations. The TIOON program and other aspiring field investigation programs will be promoted in the future.

By exploring the case of Oman TV’s broadcasting of Indian films in the 1970s and 1980s, I uncover the gulf between historiographies of national cinema and television that are framed by histories of production, on the one hand, and accounts of (new) media distribution that are framed by neoliberal contexts of globalization since the late 1990s, on the other. From archival sources, including Indian government documents and trade journals, three intriguing patterns emerge: (1) In lists of countries to which Indian films were being exported in the 1980s, the importer is mentioned, specifically and uniquely, as ‘Oman TV’ instead of ‘Oman’. (2) By the 1980s, Oman TV was a crucial conduit through which Indian films were readily and easily available to audiences in Pakistan, among other locations across the Middle East and South Asia, regardless of national import/export policies. (3) Weekly broadcasts of Indian films on Oman TV fueled demand for both VHS tapes of Indian films and the local exhibition of Indian films in cinema halls. Together, these strands reveal a key moment of infrastructure development in the Gulf, a period of burgeoning labor migrations and major shifts in transregional media distribution and viewing practices.

SUMMARYThe brutal onset of seismicity offshore Mayotte island North of the Mozambique Channel, Indian Ocean, that occurred in May 2018 caught the population, authorities and scientific community off guard. Around 20 potentially felt earthquakes were recorded in the first 5 d, up to magnitude Mw 5.9. The scientific community had little pre-existing knowledge of the seismic activity in the region due to poor seismic network coverage. During 2018 and 2019, the MAYOBS/REVOSIMA seismology group was progressively built between four French research institutions to improve instrumentation and data sets to monitor what we know now as an on-going exceptional submarine basaltic eruption. After the addition of 3 medium-band stations on Mayotte island and 1 on Grande Glorieuse island in early 2019, the data recovered from the Ocean Bottom Seismometers were regularly processed by the group to improve the location of the earthquakes detected daily by the land network. We first built a new local 1-D velocity model and established specific data processing procedures. The local 1.66 low VP/VS ratio we estimated is compatible with a volcanic island context. We manually picked about 125 000 P and S phases on land and sea bottom stations to locate more than 5000 events between February 2019 and May 2020. The earthquakes outline two separate seismic clusters offshore that we named Proximal and Distal. The Proximal cluster, located 10 km offshore Mayotte eastern coastlines, is 20–50 km deep and has a cylindrical shape. The Distal cluster start 5 km to the east of the Proximal cluster and extends below Mayotte's new volcanic edifice, from 50 to 25 km depth. The two clusters appear seismically separated, however our data set is insufficient to firmly demonstrate this.

The multiple baleen whales of the central Indian Ocean use distinct calls, with their acoustic signatures marking their respective geographic distributions. This paper uses observations from Diego Garcia to track long-term changes (2002–2019) in calls produced by an unidentified whale. The calls around 20–45 Hz consist of closely spaced frequency tones that resemble a comb, followed by a downsweep. The observations show that while the average comb frequencies steadily increase, the downsweep portion decreases. Some frequencies disappear, while new ones appear. These frequency-observations are different from similar studies of other baleen whales in the region, which mostly show a decrease.

Climate change, often identified as one of the biggest challenges of this century and beyond, affects the small island states of the Indian Ocean, Pacific and elsewhere in various ways. This includ...

Present study described the new distributional record of Peristedion liorhynchus (Gunther in Proc of the Zool Soc Lond 1871:652–675, 1872) from Central Indian Ocean. Two specimens were collected from the continental slope of Arabian Sea, India at a depth of 934 m. Previous occurrence of P. liorhynchus in the Indian Ocean only came from its eastern region. The present record of this species extends its geographical distributional area towards the Central Indian Ocean and also represents the report of third species of the genus Peristedion from this area. Present record constitutes a valuable addition to the ichthyofauna of India. Along with morphometric and meristic characters previous distributional records also discussed.

Understanding the population dynamics of highly mobile, widely distributed, oceanic sharks, many of which are overexploited, is necessary to aid their conservation management. We investigated the global population genomics of tiger sharks (Galeocerdo cuvier), a circumglobally distributed, apex predator displaying remarkable behavioral versatility in its diet, habitat use (near coastal, coral reef, pelagic), and individual movement patterns (spatially resident to long-distance migrations). We genotyped 242 tiger sharks from 10 globally distributed locations at more than 2000 single nucleotide polymorphisms. Although this species often conducts massive distance migrations, the data show strong genetic differentiation at both neutral (FST = 0.125–0.144) and candidate outlier loci (FST = 0.570–0.761) between western Atlantic and Indo-Pacific sharks, suggesting the potential for adaptation to the environments specific to these oceanic regions. Within these regions, there was mixed support for population differentiation between northern and southern hemispheres in the western Atlantic, and none for structure within the Indian Ocean. Notably, the results demonstrate a low level of population differentiation of tiger sharks from the remote Hawaiian archipelago compared with sharks from the Indian Ocean (FST = 0.003–0.005, P < 0.01). Given concerns about biodiversity loss and marine ecosystem impacts caused by overfishing of oceanic sharks in the midst of rapid environmental change, our results suggest it imperative that international fishery management prioritize conservation of the evolutionary potential of the highly genetically differentiated Atlantic and Indo-Pacific populations of this unique apex predator. Furthermore, we suggest targeted management attention to tiger sharks in the Hawaiian archipelago based on a precautionary biodiversity conservation perspective.

The atmospheric circulation changes dramatically over a few days before and after the onset of the South Asian monsoon in spring. It is accompanied by the annual maximum surface heating over the Tibetan Plateau. We conducted two sets of experiments with a coupled general circulation model to compare the response of atmospheric circulation and wind-driven circulation in the Indian Ocean to the thermal forcing of the Tibetan Plateau before and after the monsoon onset. The results show that the Tibetan Plateau's thermal forcing modulates the sea surface temperature (SST) of the Indian Ocean and the meridional circulation in the upper ocean with opposite effects during these two stages. The thermal forcing of the Tibetan Plateau always induces a southwesterly response over the northern Indian Ocean and weakens the northeasterly background circulation before the monsoon onset. Subsequently, wind-evaporation feedback results in a warming SST response. Meanwhile, the oceanic meridional circulation shows offshore upwellings in the north and southward transport in the upper layer crossing the equator, sinking near 15°S. After the monsoon onset, the thermal forcing of the Tibetan Plateau accelerates the background southwesterly and introduces a cooling response to the Indian Ocean SST. The response of oceanic meridional overturning circulation is limited to the north of the equator due to the location and structural evolution of the climatological local Hadley circulation. With an acceleration of the local Walker circulation, the underlying zonal currents also show corresponding changes, including a westerly drift along the equator, downwelling near Indonesia, offshore upwelling near Somalia, and a westward undercurrent.

The alarming rate of abrupt change in weather parameters, especially rainfall and temperature, is a cause of major concern not only for the scientific community but also for the lives of common people living in a country like India. A broad picture of climate change is not sufficient to carry out an impact assessment on a regional scale. Recent news on the occurrence of floods on a regional scale over India throws an urgent need to look at the patterns of changes in rainfall on a more regional scale. Kerala, the southwestern state of the Indian peninsula, is known to be the gateway of monsoon for the summer monsoon season to the mainland. This study is evaluating the causes of the recent variability in the rainfall pattern over Kerala during the southwest monsoon season. It is found that the Kerala rainfall is decreasing at the rate of 3 mm/year for the past 100 years, with an abrupt decrease of 6.7 mm/year after 1960. The causes of such a decrease are a point of discussion in this study. It is found that the ocean parameters such as sea surface temperature, ocean heat content and ocean heat fluxes are increasing at an alarming rate in the recent decade over the North West Equatorial Indian Ocean, including the Arabian sea. The pattern of the Findlater jet and the ocean response clearly identifies the North West Equatorial Indian Ocean as a hot spot which creates maximum variability in the southwest monsoon dynamics.

Knowledge about spatial and temporal variability in the distribution and abundance of predators is necessary to adapt measures to mitigate human–wildlife interactions. Acoustic telemetry and network analyses were used to investigate the spatial ecology of bull sharks, the species responsible for most shark bites in Reunion Island, one of the world's shark bite hotspots. The west coast of the island was not used uniformly by every individual, with size predicting the movements of sharks along the coast. Node-based metrics – closeness, node strength, and cumulated continuous residency times – derived from up to 181 monthly movement networks from 20 individuals, revealed that smaller sharks (

Initial errors in the tropical Indian Ocean (IO-related initial errors) that are most likely to yield the Spring Prediction Barrier (SPB) for La Nina forecasts are explored by using the CESM model. These initial errors can be classified into two types. Type-1 initial error consists of positive sea temperature errors in the western Indian Ocean and negative sea temperature errors in the eastern Indian Ocean, while the spatial structure of Type-2 initial error is nearly opposite. Both kinds of IO-related initial errors induce positive prediction errors of sea temperature in the Pacific Ocean, leading to under-prediction of La Nina events. Type-1 initial error in the tropical Indian Ocean mainly influences the SSTA in the tropical Pacific Ocean via atmospheric bridge, leading to the development of localized sea temperature errors in the eastern Pacific Ocean. However, for Type-2 initial error, its positive sea temperature errors in the eastern Indian Ocean can induce downwelling error and influence La Nina predictions through an oceanic channel called Indonesian Throughflow. Based on the location of largest SPB-related initial errors, the sensitive area in the tropical Indian Ocean for La Nina predictions is identified. Furthermore, sensitivity experiments show that applying targeted observations in this sensitive area is very useful in decreasing prediction errors of La Nina. Therefore, adopting a targeted observation strategy in the tropical Indian Ocean is a promising approach toward increasing ENSO prediction skill.

Naobranchia cygniformis Hesse, 1863 is one of 21 accepted species of the genus Naobranchia, which is distinguished from other genera in the family Lernaeopodidae by the possession of ribbon-like maxillae. The original description of N. cygniformis lacked detail concerning the armature, and later reports have not included a redescription. Thus, a redescription with details regarding the armature will be valuable for future comparative purposes. Additionally, this report of this parasitic copepod on the seabream Pagellus natalensis from the east coast of South Africa constitutes a new host and geographic record, since the only other Naobranchia species reported from the Indian Ocean off South Africa are N. kabatana and N. pritchardae.

On January 28, 2021, a Special Chamber of the International Tribunal for the Law of the Sea (ITLOS) delivered a judgment in which it rejected preliminary objections raised by the Maldives in arbitral proceedings instituted by Mauritius, concerning the delimitation of the maritime boundary north of the Chagos Archipelago in the Indian Ocean.

Batee Island is one of the small islands in the Aceh Besar region and is uninhabited and directly faces the Indian Ocean. Batee Island's waters have the potential for marine biota, especially coral reef ecosystems, and other associated biotas. This study aims to determine the percentage and comparison of live coral cover in Batee Island waters and determine the genus' composition in Batee Island waters. This research was conducted in October-November 2016. Collecting coral reef data using the LIT (Line Intercept Transect) method. The results showed that the live coral cover in Batee Island's waters differed between the East and West Batee Islands. The coral reefs' average condition in Batee Island waters at shallow depths (0-5m) is 41.41%, and deep (6-10m) is 36.52%. Overall, the conditions and live coral cover in the waters of Batee Island are classified as moderate. In the waters of Batee Island, there are 31 coral genera. The highest percentage of corals was the genus Acropora (50.02%).Keywords:Batee IslandConditionCoral reefCoral cover

Intended to provide accurate knowledge of the Red Sea at the dawn of the 16th century, the Letters of Afonso de Albuquerque (1452‑1515), appointed first governor of the “Estado da Índia” (1509‑1515) do not deal exclusively with the commercial and geopolitical dynamics of the region. In spite of the significance of these issues, they also contain valuable geographical descriptions of the insular world and the shores of the Red Sea (“Mar Roxo”), explored in 1513 by Albuquerque in his attempt to conquer Aden. This article examines the most significant information about this area – coastal morphologies, ports, anchorages –, navigation practices and political geography, reported in the wake of the 1513 campaign, which, as it should be recalled, intended to gather strategic information to block the entrance of the Red Sea, which was largely dominated by the Mamluk sultanate, the fierce enemy of the Portuguese, at the beginning of the 16th century. Véritable somme des connaissances sur la mer Rouge à l’aube du xvie siècle, les Lettres d’Afonso de Albuquerque (1452‑1515), premier gouverneur de l’« Estado da Índia » (1509‑1515), ne traitent pas seulement des dynamiques commerciales et géopolitiques de la région. Elles comportent également de précieuses descriptions géographiques du monde insulaire et des rives du « Mar Roxo », explorées par l’escadre d’Albuquerque lors de sa tentative de s’emparer d’Aden en 1513. Le présent article se proposera d’examiner les informations les plus significatives sur ces espaces – la morphologie des côtes, les ports, les mouillages –, les pratiques de navigation et les aspects de géographie politique, reportés dans la foulée de la campagne de 1513, qui, il faut le rappeler, visait à recueillir des informations stratégiques en vue de bloquer l’entrée de la mer Rouge, largement dominée par le sultanat mamelouk, adversaire principal des Portugais au début du xvie siècle.

The China–Indochina Peninsula Economic Corridor, with Nanning, Guangxi and Kunming, Yunnan as the starting points and Singapore as the end, passes through the Indochina Peninsula, covering the 6 major ASEAN members—Vietnam, Laos, Cambodia, Thailand, Malaysia and Singapore. The Indochina Peninsula, located between China and the South Asia subcontinent, and between the Indian Ocean and the Pacific Ocean, with unique location advantages and geographical advantages, has historically been the pivot of the Maritime Silk Road. The Lancang–Mekong International Waterway and the cross-border traffic and oil and gas networks under construction link the Land and Sea Silk Road closely together. The China–Malaysia Qinzhou Industrial Park and the Malaysia–China Guandan Industrial Park have become the model of cooperation between China and Malaysia. The Cambodia Sihanoukville Special Economic Zone has become a model of the win–win cooperation between China and Cambodia.

Before the onset of the industrial revolution, China and India were the two biggest powers in Eurasia. Their total population comprised almost half of the world’s population. And the GNP of premodern China was half of the combined GNP of the world. Before circa 1600 CE, most of the textiles and iron in the world were manufactured in these two countries. China and India suffered a temporary eclipse during the age of colonialism. However, with the rise of the economic and military power of China and India from the late 20th century, it seems that these two countries are bound to reclaim their traditional positions as big powers in the international system. However, there is a caveat. In the premodern era, the Himalayas prevented any intimate contact between the ‘dragon’ and the ‘elephant’. But, from the mid-20th century, advances in technology, economic competition and the annexation of Tibet by the People’s Republic of China (PRC) among other factors resulted in China and India coming into direct contact with each other. The result has been cooperation–competition–conflict. And this has had consequences not only for these two countries but for the whole world. The present article attempts to trace the troubled trajectory of India’s China policy from the late 1940s (when these two countries became independent) up to the present day.