Northeastern Coast Research Articles

Whispers of Wisdom: Exploring the Essence of Partandaan in the Suluk Indigenous Mediation

The Orang Suluk, who call themselves Tausug, have a deep history in the sea areas and are known for their strong cultural and political independence. Residing in the Sulu Archipelago and the northeastern coast of Borneo, they identify themselves by names such as Suluk, Anak Negeri, coastal people, sea people, indigenous maritime group, and Orang Asal Pesisir. Symbols are a part of the Suluk Indigenous Mediation (SIM) approach, which is still practiced on the east coast of Sabah, Malaysia. The techniques mentioned are organic to the Adat (customs) of the Suluk passed down from their forefathers. This study discusses the essence of partandaan (symbols) found in SIM practices of the Suluk mediators in the said geographical area. Five expert informants in Semporna, Lahad Datu, and Sandakan shared their wisdom, experience, and interpretation of the SIM during the in-depth interviews as empirical data. The researchers also did library work to collect secondary data. Employing Hewitt’s Symbolic Interactionism (2002), findings revealed that objects, social acts, and language carry symbols that are meaningful to the life of the Suluk. They influence the thinking of the Tausug, maintain the balance and harmony of their day-to-day life, and crystalize the vision of peace, understanding, and forgiveness. Indeed, symbols are fruitful tools for successful culturally and religiously sensitive mediation. The study highlights the significance of symbols in Suluk Indigenous Mediation, suggesting further exploration of cultural variations and the potential integration of symbolic elements into conflict resolution mechanisms.

Mixed-marker data indicate the population biology, history, and the stock structure of crevalle jack Caranx hippos (Linnaeus, 1766) in the tropical Atlantic: A regional and latitudinal conservation genetics approach

The crevalle jack Caranx hippos (Carangidae: Caranginae) is a commercially important carangid, especially along the Brazilian Northeastern coast. However, little is known about its population structure and genetic diversity, which is crucial information for species conservation. Using mitochondrial [barcode region COI and control region] and nuclear (first intron S7) data, we investigated the genetic structure and demographic history of C. hippos along the Brazilian Northeastern coast, and included the COI public database to provide a latitudinal approach. Both mitochondrial markers revealed two coexistent lineages along the Brazilian Northeastern coast, while the nuclear DNA did not recover any signals of structure. This mitonuclear discordance can be explained by both male dispersal and demographic history, which seem to be closely related to the Pleistocene period. Over the glacial cycles, the lineages may have used different refuges, regaining contact during the interglacial cycles. This hypothesis of previous allopatry is reinforced by the profound genetic distance found. The latitudinal approach reveals a deep differentiation between the Carolina and both Brazilian and Caribbean Provinces, with high and significant FST pairwise values, such that the tropical-temperate climate transition may be acting as a gene flow barrier between them. Thus, we suggest two preliminary stocks for C. hippos in the Atlantic: (1) Carolina and (2) Brazilian and Caribbean Provinces.

A new species of planthopper in the genus Colpoptera (Hemiptera: Fulgoroidea: Nogodinidae) from the Northeastern coast of Jamaica

A new species of Colpoptera Burmeister, 1835, C. japortla sp. nov. (Colpopterinae: Colpopterini), is described from Jamaica. The new species was found during a survey of planthoppers associated with coconut palms to document taxa that are potential phytoplasma vectors. Molecular data for the five-prime region of the cytochrome c oxidase subunit I (COI) gene and 18S rRNA gene is provided and compared to available members of Colpopterini. Syntypes of Colpoptera rugosa Van Duzee borrowed for comparison with the new species were found to be a mixed series including representatives of Jamaha elevans (Walker). A lectotype designation, with an amended diagnosis, is made for Colpoptera rugosa, to preserve the stability of nomenclature and this species is transferred to Jamaha as J. rugosa, comb. nov.

Kuzeydoğu Ege Denizi’nde (Türkiye) Diplodus sargus (Linnaeus, 1758)'un bazı biyolojik özellikleri

In the study, the age, growth, mortality parameters and length-weight relationship parameters of Diplodus sargus (white seabream) collected by a small-scale fisherman between August 2020 and July 2021 along the northeastern coast of Aegean Sea (Türkiye coast), were investigated. D. sargus had a range of total length and weight from 14.3 cm to 36.7 cm and from 50.5 g to 836.5 g, respectively. The length-weight relationships (LWRs) were calculated as W=0.02368*L2.881 for females, W = 0.01847*L2.959 for males and W = 0.01989*TL2.936 for both sexes. Using data from fish scales, the maximum age was determined to be 11 years. von Bertalanffy growth parameters have been calculated as follows L∞=39.01 cm TL, K=0.13 year-1, and t0= -2.58 year for both sexes combined. Total (T), natural (N) and fishing (F) mortalities were defined as Z: 0.83 year-1, M: 0.33 year-1 and F: 0.50 year-1 for both sexes combined. The exploitation rate (E) was calculated as 0.70, 0.44 and 0.60 for females, males and combined, respectively.

Biodiversity patterns of macrofauna associated with Halodule wrightii (Ascherson) in meadows of north-eastern Brazil

Context Seagrass meadows are highly productive habitats with a vast species diversity that perform multiple ecosystem services. The fauna associated with these environments is responsible for many of the ecosystem services. Therefore, the fauna composition and functional characteristics should be considered in studies addressing seagrass meadows. Aims This study aimed to evaluate the differences in the taxonomic and functional compositions of the macrofauna associated with Halodule wrightii (Ascherson) meadows subject to different settings of habitat characteristics in the shallow coastal regions of the north-eastern coast of Brazil. Methods We used the Hill diversity series to estimate taxonomic diversity, whereas functional diversity was estimated through biological-trait analyses. Key results Distinct patterns of taxonomic and functional diversities were observed among meadows. However, the composition of functional traits diverged more. Lower taxonomic and functional diversity were observed in the Suape meadows, with values mainly related to the low organic matter content. Catuama meadows presented opposite results, associated with higher organic matter and plant density. Conclusions The meadow heterogeneity can influence the associated macrofauna and its functional characteristics. Implications These results are highly relevant for predicting the consequences of changes in seagrass meadows and how this affects the functioning of these ecosystems.

Unusual Hemiaulus bloom influences ocean productivity in Northeastern US Shelf waters

Abstract. Because of its temperate location, high dynamic range of environmental conditions, and extensive human activity, the long-term ecological research site in the coastal Northeastern US Shelf (NES) of the northwestern Atlantic Ocean offers an ideal opportunity to understand how productivity shifts in response to changes in planktonic community composition. Ocean production and trophic transfer rates, including net community production (NCP), net primary production (NPP), gross oxygen production (GOP), and microzooplankton grazing rates, are key metrics for understanding marine ecosystem dynamics and associated impacts on biogeochemical cycles. Although small phytoplankton usually dominate phytoplankton community composition and Chl a concentration in the NES waters during the summer, in August 2019, a bloom of the large diatom genus Hemiaulus, with N2-fixing symbionts, was observed in the mid-shelf region. NCP was 2.5 to 9 times higher when Hemiaulus dominated phytoplankton carbon compared to NCP throughout the same geographic area during the summers of 2020–2022. The Hemiaulus bloom in summer 2019 also coincided with higher trophic transfer efficiency from phytoplankton to microzooplankton and higher GOP and NPP than in the summers 2020–2022. This study suggests that the dominance of an atypical phytoplankton community that alters the typical size distribution of primary producers can significantly influence productivity and trophic transfer, highlighting the dynamic nature of the coastal ocean. Notably, summer 2018 NCP levels were also high, although the size distribution of Chl a was typical and an atypical phytoplankton community was not observed. A better understanding of the dynamics of the NES in terms of biological productivity is of primary importance, especially in the context of changing environmental conditions due to climate processes.

Morphological, chemical and growth patterns characterization in shells of Phorcus species along the northeastern coasts of Tunisia

This work is a characterization of the morphometry, the relative growth and the metal contamination degree of the shells of two species belonging to Phorcus genus along the northeastern rocky coasts of Tunisia. The gastropods were sampled from nine locations during the winter 2017. Our findings suggested a spatial morphometric variability probably linked to the extent of the continental shelf, the coasts’ geomorphology, the dynamics of water masses, the predation and the competition effects. Furthermore, the shell investigation allowed the study of the growth pattern and indicated that the development in shell size was faster than the increase in weight. Moreover, the use of Phorcus shells as bioindicators of long-term metal contamination seems to be of growing interest, due to their abundance, high longevity, easy sampling and ecobiological features, both in a scientific and ecosystem management perspective that aims to the establishment of conservation measures targeting marine coastal environments.

Structure of the Plio-Quaternary coastal aquifer (Mediterranean Basin, Tunisia): insights from gravity and seismic analysis

This research paper presents an investigation of an aquifer structure using a combination of gravity and seismic analyses, calibrated by hydrogeological data. This work illustrates how crucial it is to study geological structures and fault networks as preliminary work to understand water- and pollutant-flow systems and aquifer vulnerability, especially with the increased frequency of drought events and climate change pressures. A Plio-Quaternary coastal northeastern aquifer in Tunisia was chosen as the study case. First, a hydrogeological approach was performed using water wells, and piezometer data showed an important fluctuation in the piezometric level and a notable depression in the piezometric surface observed in the southern part of the study area. Secondly, gravity data were analysed and calibrated using a seismic profile. The results demonstrated the presence of shallow NE–SW faults less than 300 m below the region's principal wadis, as well as deeper faults of varying depths (from 400 to 2600 m) that influence the basin structure, aquifer geometry and resulting water flow. The combination of these approaches revealed that the variations in the aquifer thickness, piezometric surface depression zones and groundwater flow are mainly controlled by shallow and deep geological structures and their tectonic reactivation.

Evidence for adaptive strategies in larval capelin on the northeastern coast of Newfoundland, Canada

Abstract Fish species with high mortality during early life may maximize fitness using adaptive strategies to time hatching to match favorable environmental conditions (match/mismatch) or extending spawning/hatching to disperse risk (bet-hedging). We examined support for these strategies in a collapsed forage fish, capelin (Mallotus villosus), in coastal Newfoundland (2018–2021). Capelin shift from spawning at warm, intertidal to cool, subtidal (15–40 m) habitats in warmer years, with unknown recruitment consequences. We hypothesized that match/mismatch (specifically, Coastal Water Mass Replacement Hypothesis) would be supported if densities of recently hatched larvae showed pulses that overlapped with high prey and low predator densities. Generalized additive models revealed that larval densities increased with zooplankton prey biomass, but were not influenced by predator biomass or temperature, contrasting with pre-collapse studies and providing equivocal support for match/mismatch. Protracted larval emergence and previously documented high variability in larval traits supported a bet-hedging strategy. Larval condition (i.e. length, yolk-sac diameter) did not differ between habitats but varied among years, where the highest proportion of larvae in poor condition was from the intertidal site in the warmest year (2018). Findings suggest that spawning habitat shifts may have limited impact on stock recovery relative to year-specific environmental conditions that influence larval condition.

Московская компания и английские экспедиции в Северную Америку в последней четверти XVI века

The introduction of the article includes the justification of the necessity to determine the role of the English Muscovy Company in the study of the geography of North America in the last quarter of the 16th century. The monopoly of the Muscovy Company and the significance of this commercial firm in the discovery of the northeast coast and Arctic waters of North America have not yet been studied. Documents (charters, reports, letters, petitions, and treatises) directly related to the organization of English voyages to the American Arctic waters, as well as diplomatic documents, are used as materials. Analysis. The reasons and circumstances of the Muscovy Company’s monopoly on the search for the North-West Passage in North America are studied. The company’s contribution to the organization of the expeditions of Martin Frobisher in 1576 and John Davis in 1585– 1587 is determined. The attempts of the Cathay Company and Humphrey Gilbert at the turn of the 1570s–1580s to deprive “Muscovite” merchants of this privilege are analyzed. It is proven that even at the beginning of the 17th century, the Moscow Company retained a monopoly on the exploration of the Arctic seas. Results. With its monopoly on the search for the North-West Passage and its organizational and financial support, the Muscovy Company made an important contribution to the exploration of the north-eastern coast of North America in the last quarter of the 16th century. English navigators had the opportunity to explore Arctic waters, step by step shaping the modern geographical shape of North America on maps.

Trophic ecology of sympatric sea turtles in the tropical Atlantic coast of Brazil

The Tropical Atlantic coast of Brazil is a hotspot area for multiple sea turtle species at all life stages. The multiple nearshore reefs and beaches, oceanic islands, and the only atoll in the south Atlantic Ocean, are suitable for year-round foraging, migration corridors, and nesting activities of five sea turtle species. Still, relatively few studies have assessed trophic niche among sympatric sea turtles which can provide a better understanding of how closely related species compete/partition the available resources. Using multiple biogeochemical tracers (i.e., nitrogen (δ15N) and carbon (δ13C) stable isotopes, and mercury (Hg)), we disentangled the trophic niches of four sea turtle species – the green turtle (Chelonia mydas), the loggerhead turtle (Caretta), the hawksbill turtle (Eretmochelys imbricata), and the olive ridley turtle (Lepidochelys olivacea) – co-occurring in nesting and foraging habitats along the northeastern coast of Brazil. We found interspecific differences in isotopic and contamination niches, as well as intraspecific niche variation associated with life stage. Differences in the estimation niche models associated to life-stage in C. caretta support the notion of ontogenetic shift in habitat and diet composition previously reported for this species. Oceanic habitat signatures were observed in juvenile green turtles and adult olive turtles, while nearshore habitat signatures were observed in adult hawksbill turtles.

A Broad-scale Biometrical Response of Pristine Posidonia Oceanica Meadow to Winter and Summer Conditions in the North-eastern Mediterranean Coast

A Broad-scale Biometrical Response of Pristine Posidonia Oceanica Meadow to Winter and Summer Conditions in the North-eastern Mediterranean Coast

Genetic structuring and species boundaries in the Atlantic stony coral Favia (Scleractinia, Faviidae)

AbstractScleractinian corals are the main modern builders of coral reefs, which are major hot spots of marine biodiversity. Southern Atlantic reef corals are understudied compared to their Caribbean and Indo‐Pacific counterparts and many hypotheses about their population dynamics demand further testing. We employed thousands of single nucleotide polymorphisms (SNPs) recovered via ezRAD to characterize genetic population structuring and species boundaries in the amphi‐Atlantic hard coral genus Favia. Coalescent‐based species delimitation (BFD* – Bayes Factor Delimitation) recovered F. fragum and F. gravida as separate species. Although our results agree with depth‐related genetic structuring in F. fragum, they did not support incipient speciation of the ‘tall’ and ‘short’ morphotypes. The preferred scenario also revealed a split between two main lineages of F. gravida, one from Ascension Island and the other from Brazil. The Brazilian lineage is further divided into a species that occurs throughout the Northeastern coast and another that ranges from the Abrolhos Archipelago to the state of Espírito Santo. BFD* scenarios were corroborated by analyses of SNP matrices with varying levels of missing data and by a speciation‐based delimitation approach (DELINEATE). Our results challenge current notions about Atlantic reef corals because they uncovered surprising genetic diversity in Favia and rejected the long‐standing hypothesis that Abrolhos Archipelago may have served as a Pleistocenic refuge during the last glaciations.

Anti-inflammatory constituents from a sea anemone-derived fungus Arthrinium arundinis MA30

In this study, preliminary field-sampling of bioactive fungal strains and bioassay-guided selection were conducted. A number of fungal strains were isolated from sea anemones along the northeastern coast of Badouzi, Keelung, Taiwan. Among them, Arthrinium arundinis MA30 showed significant anti-inflammatory activity and was thus selected for further chemical investigation. After a series of purification and isolation using different chromatographic techniques on the fermented products of A. arundinis MA30, thirty-one compounds were identified, five of which were previously unreported, including arthrinoic acid, hexylaconitic anhydride methyl ester, (3S,8R)-8-hydroxy-3-carboxy-2-methylenenonanoic acid, and arthripenoids G and H. These compounds were subjected to comprehensive spectroscopic data analysis. Of all the isolates, 1,3,5,6-tetrahydroxy-8-methylxanthone and arthripenoid C demonstrated the most distinctive inhibitory activities against nitric oxide production in mouse microglial BV-2 cells, with their respective inhibitory rates being 71% and 81% at 10 μM concentration, and their respective IC50 values were further determined to be 5.3 ± 0.6 and 1.6 ± 0.4 μM. These compounds showed no significant cytotoxicity, and curcumin was used as a positive control in this study.

Transcriptomic Response of the Atlantic Surfclam (Spisula solidissima) to Acute Heat Stress

There is clear evidence that the oceans are warming due to anthropogenic climate change, and the northeastern coast of USA contains some of the fastest warming areas. This warming is projected to continue with serious biological and social ramifications for fisheries and aquaculture. One species particularly vulnerable to warming is the Atlantic surfclam (Spisula solidissima). The surfclam is a critically important species, linking marine food webs and supporting a productive, lucrative, and sustainable fishery. The surfclam is also emerging as an attractive candidate for aquaculture diversification, but the warming of shallow coastal farms threatens the expansion of surfclam aquaculture. Little is known about the adaptive potential of surfclams to cope with ocean warming. In this study, the surfclam transcriptome under heat stress was examined. Two groups of surfclams were subjected to heat stress to assess how artificial selection may alter gene expression. One group of clams had been selected for greater heat tolerance (HS) and the other was composed of random control clams (RC). After a 6-h exposure to 16 or 29 °C, gill transcriptome expression profiles of the four temperature/group combinations were determined by RNA sequencing and compared. When surfclams experienced heat stress, they exhibited upregulation of heat shock proteins (HSPs), inhibitors of apoptosis (IAPs), and other stress-response related genes. RC clams differentially expressed 1.7 times more genes than HS clams, yet HS clams had a stronger response of key stress response genes, including HSPs, IAPs, and genes involved with mitigating oxidative stress. The findings imply that the HS clams have a more effective response to heat stress after undergoing the initial selection event due to genetic differences created by the selection, epigenetic memory of the first heat shock, or both. This work provides insights into how surfclams adapt to heat stress and should inform future breeding programs that attempt to breed surfclam for greater heat tolerance, and ultimately bring greater resiliency to shellfish farms.

Sudden arrival of marine litter on the northeastern coast of Brazil: Physical forcings and associated transport

This study made use of four asynchronously coupled numerical simulations (four Eulerian and four Lagrangian) to investigate an event of a sudden arrival of more than 50 tons of marine litter on the northeastern Brazilian coast. This material mysteriously landed on several beaches, compromising water quality and impacting tourism, therefore raising serious concerns about its origin from local authorities. A total of 87,030 virtual particles were released and had their trajectories investigated, as well as their relationship with major physical forcings, including tides, winds and the North Brazil Under Current (NBUC). The virtual particles followed predominantly towards the north/northwest, mainly due to the presence of the NBUC and southeast trade winds. This pattern indicated that the flow of marine surface litter followed the continental shelf northwards, and the role of winds was key in providing the conditions for oceanic originated material to being deposit along the coastline. This study provided important insights about the regional circulation and main forcings that act in the transport and deposition of floating materials that reach the shallow shelf of the Brazilian northeast. Further investigation on the variability of these forcings along the seasonal cycle seems to be extremely important and should be undertaken soon.

An erroneous record of Perna viridis (Linnaeus, 1758) (Bivalvia, Mytilidae) for the northeastern coast of Brazil, Southwestern Atlantic

An erroneous record of Perna viridis (Linnaeus, 1758) (Bivalvia, Mytilidae) for the northeastern coast of Brazil, Southwestern Atlantic

Observed Extreme Freshening in the Central Andaman Sea Induced by Strong Positive Indian Ocean Dipole

AbstractThe Indian Ocean Dipole (IOD) has been extensively studied for its significant impact on salinity distribution in tropical regions. However, its off‐equatorial influence in the northeastern Indian Ocean (IO) has received limited documentation thus far. In October 2019, a buoy in the central Andaman Sea (AS) observed an extreme freshening event that resulted in intensified upper‐ocean stratification and increased internal wave activities. The salt budget evaluation revealed the dominant role of horizontal advection. Interannual variability in autumn and winter sea surface salinity (SSS) showed a significant correlation with the IOD. Extreme freshening was observed exclusively during strong positive IOD (pIOD) years. This freshening primarily resulted from the outflow of low‐salinity water from the northeastern coast of the AS, driven by an anomalous anti‐cyclonic coastal‐trapped circulation exclusive to strong pIODs in the northeastern IO. This circulation tends to hinder southward freshwater transport in the western region while enhancing it in the eastern region. This circulation pattern is primarily influenced by Kelvin wave forcing, which is triggered by robust equatorial easterly anomalies that are typically more pronounced during strong pIOD events and weaker during weak pIOD events. The anticipated increase in the frequency of extreme freshening events due to the greenhouse warming has the potential to significantly modify the salinity distribution and freshwater transport in the future.

Report on the Excavations at Kuchchaveli, Sri Lanka (2011)

We report the archaeological findings from the historic site of Kuchchaveli in the northeastern coast of Sri Lanka, based on our excavations in 2011. The Kuchchaveli complex revealed features of a Mahāyāna Buddhist centre during the 7th and 8th centuries as indicated by the structures and an inscription as well as a number of Buddhist sculptures and carvings. Archaeological material and a radiocarbon date of 1880 ± 30 BP from a test pit indicate an earlier occupation as well. Our excavations offered insights to the structures built at Kuchchaveli and yielded pottery fragments, glass beads, faunal remains and other artefacts of interest. This report highlights findings from six test pits, where two test pits correspond to the possible bodhigara and water tank of the monastery. The similarity of the Kuchchaveli glass finds to those from other sites in Sri Lanka highlights the internal circulation of glass beads during the period that Kuchchaveli was an active site. The faunal remains suggest that a mix of domesticated and wild animals were part of the diet in the community. Apart from being a monastic establishment linked to the southeast coast of India, Kuchchaveli revealed trade activities with other regions over a long period, particularly in the Middle Historic Period of the region.

Uneven demographic consequences of the 2022 disease outbreak for the sea urchin Diadema antillarum in Puerto Rico.

Pervasive epizootic events have had a significant impact on marine invertebrates throughout the Caribbean, leading to severe population declines and consequential ecological implications. One such event was the regional collapse of herbivory, partly caused by the Diadema antillarum mortality event in 1983-84, resulting in a trophic cascade and altering the structure of reef communities. Consequently, there was a notable decrease in coral recruitment and an increase in the coverage of macroalgae. Nearly four decades later, in early 2022, the Caribbean basin experienced another widespread mass mortality event, further reducing the populations of D. antillarum. To assess the effects of this recent mortality event on the current demographics of D. antillarum, we surveyed eight populations along the eastern, northeastern, northern, and northwestern coast of Puerto Rico from May to July 2022, estimating their population density, size distribution, and disease prevalence. Additionally, the study compared these population parameters with data from four sites previously surveyed in 2012 and 2017 to understand the impact of the recent mortality event. The survey conducted in 2022 showed varying population densities at the surveyed reefs. Some populations exhibited mean densities of nearly one individual per square meter, while others had extremely low or no living individuals per square meter. The four populations with the highest density showed no evidence of disease, whereas the four populations with the lowest D. antillarum densities exhibited moderate to high disease prevalence. However, when considering all sites, the estimated disease prevalence remained below 5%. Nevertheless, the comparison with data from 2012 and 2017 indicated that the recent mortality event had a negative impact on D. antillarum demographics at multiple sites, as the densities in 2022 were reduced by 60.19% compared to those from the previous years. However, it is still too early to determine the severity of this new mortality event compared to the 1983-84 mortality event. Therefore, it is imperative to continue monitoring these populations.