Adjacent Waters Research Articles

Marine Heatwave Characteristics in the Makassar Strait and Its Surrounding Waters

This study aimed to investigate the characteristics of marine heatwaves (MHWs) in the Makassar Strait and adjacent waters (MSAW) using the Optimum Interpolation Sea Surface Temperature (OISSTv2) dataset from 1982 to 2021. The analysis revealed a significant positive trend in the frequency and duration of MHWs, while the mean and maximum intensities displayed a negative trend over the 40-year period. By examining two different phases of the Pacific Decadal Oscillation (PDO), it was observed that the cold phase (more frequent La Niña events than El Niño) had higher MHW frequency and duration, whereas the warm phase (more frequent El Niño events than La Niña) exhibited higher mean and maximum intensities. Moreover, the occurrence of high-intensity MHWs was associated with weakened winds, the decaying phase of El Niño and positive Indian Ocean Dipole (IOD), and high net surface heat flux (NSHF). An intriguing finding emerged, indicating a notable lag of 7–9 months (10 months) between El Niño (positive IOD) events and the emergence of high-intensity MHWs. This lag suggests that MHWs are more likely to manifest during the transition towards La Niña and negative IOD conditions. Additionally, the study highlighted a stronger correlation between the El Niño–Southern Oscillation and MHW intensity in the MSAW compared to the IOD. Furthermore, the different intensities of MHWs were found to be linked to NSHF, which exhibited higher values during the warm phase of the PDO compared to the cold phase.

Non-Point Sources (Septic Tanks) of Surface Water Nutrient Pollution: A Review and a Study of Taylor Creek, Okeechobee County, Florida

This study investigated the impact of high-density septic systems (aka Onsite Sewerage and Disposal Systems, OSTDS) along the canals located in the communities of the lower Taylor Creek area on water quality at the northern periphery of Lake Okeechobee. Using sucralose as an anthropogenic tracer, we investigated the septic derived non-point sourcing of nutrients which feed harmful algal (cyanobacterial) blooms (HABs) in Lake Okeechobee and adjacent waters. 
 
 The subdivisions investigated were Treasure Island (TI) and Taylor Creek Isles (TCI) located to the east and west of Taylor Creek. TI homes are all on septic tanks whereas TCI is serviced by a municipal vacuum sewerage system.
 
 TI canals had 5.3 times the mean concentration of sucralose relative to TCI canals. On a yearly basis, the Treasure Island sites away from Taylor Creek had 2.25 times the total phosphorus and 1.20 times the total nitrogen compared to the Taylor Creek isles sites. An extensive literature review of non-point pollution is included.

Distribution and Abundance of California (Zalophus californianus) and Steller (Eumetopias jubatus) Sea Lions in the Inshore Waters of Washington, 2013-2016

Two species of sea lions occur in the in387land waters of Washington State: the California sea lion (Zalophus californianus) and the Steller sea lion (Eumetopias jubatus). Both species breed elsewhere, but they typically move into Puget Sound and adjacent waters of the Salish Sea from autumn through spring. There is a need for information on their current abundance and seasonal use patterns as both species prey heavily on threatened/endangered stocks of salmon and steelhead trout (Oncorhynchus spp.), and empirical abundance estimates of these species are lacking for inland Washington waters. From 2013 to 2016, we conducted 39,399 km of aerial surveys for marine mammals in this area, sighting 255 groups of sea lions. We used a subset of 7,841 km of effort and 165 sea lion sightings made during surveys in good sighting conditions to estimate in-water abundance using line-transect methods. Historical tagging data collected in Pacific Northwest waters were used to evaluate the proportions of time that each species spent on land and conducting dives, and then to develop correction factors to derive total abundance for both sea lion species, providing the first empirical abundance estimates for these waters. We estimated that between 33 and 442 California sea lions were found in Puget Sound/Hood Canal in different seasons, with nearly 3,000 being found in the broader inland Washington waters in the peak season (spring). Steller sea lions occurred in much smaller numbers, with a peak of 219 animals in Puget Sound/Hood Canal/Strait of Juan de Fuca in autumn (and possibly as many as 600 to 700 in the entire study area). While some estimates suffer from low precision, this study demonstrates that substantial numbers of sea lions use waters of the study area throughout much of the year. Our results provide an important step toward a better understanding of these two species in the inland waters of Washington, as well as their potential effects on protected salmonid prey species.

Wave climate characteristics and effects of tropical cyclones on high wave occurrences in Indonesian waters: Strengthening sea transportation safety management

Tropical cyclones can cause bad weather and high waves that can endanger maritime activities, especially in the waters of Indonesia, which is a maritime country. Understanding ocean wave climate characteristics and the effect of Tropical Cyclones (TCs) on high wave occurrences is important, particularly to ensure the safety of fisheries activities in Indonesian seas. We aim to do so by focusing on Indonesia's 11 Fisheries Management Areas (IFMAs) using descriptive and inferential statistics. Wind and wave data were taken from the European Center for Medium-Range Weather Forecast (ECMWF), namely ECMWF Reanalysis v5 (ERA5) within the range of 42 years (1979–2020), whereas the TC data were from the International Best Track Archive for Climate Stewardship (IBTrACS). We found that significant wave heights (SWHs) in the inner seas are strongly related to monsoonal wind fields. The maximum SWH occurred in northern Indonesian seas during December–February (DJF), while occurring in southern and inner seas between June–August (JJA). The highest extreme SWH and probability of exceedance (PE) for SWH >2 m were found in IFMAs facing the open ocean, such as Malacca Strait, Western Sumatra waters, Southern Java waters, Natuna Sea, Sulawesi Sea, and Northern Papua waters. We found that TCs activity in adjacent Indonesian waters could increase anomalous SWH occurrences. Positive SWH anomalies ranged from 0.1 to 0.4 m and varied depending on TC location and season. TC that forms in the following areas increase the PE for SWH >2 m: (1) Bay of Bengal: Western Sumatra waters (March–May, MAM) around 20%; (2) Western Pacific Ocean: Northern Papua waters (DJF) around 5%; (3) Northeastern Indian Ocean: Western Sumatra waters (DJF) about 3%; and (4) Western and Northern Australian waters: Southern Java waters (DJF) about 20%. The results of this study can serve as an early assessment for investigating wave climate characteristics and identifying the areas in Indonesian waters that are most susceptible to the impact of TCs, particularly in IFMAs. These findings hold significant value for managers and policy authorities, such as the Ministry of Transportation and the Ministry of Marine Affairs and Fisheries of the Republic of Indonesia. They can utilize this information to develop measures aimed at reducing vulnerabilities among marine resource users, specifically fishers, and improving fishing vessel safety. Additionally, these findings can be utilized to enhance advance warnings and forecasts, enabling marine managers to implement strategies that minimize the impact of extreme events and increase resilience in the face of ocean and coastal disasters.

The relative importance of environmental heterogeneity and dispersal limitation on spatial patterns of phytoplankton communities varies across seasons

AbstractEnvironmental heterogeneity and dispersal limitation structure community assembly, but there is limited knowledge on how their effects vary on temporal scale. This study compiled a series of data, including phytoplankton, seawater depth and chemistry from 104 sites, to explore the spatial patterns and their drivers of phytoplankton communities in the Beibu Gulf and adjacent waters, located in the northwestern South China Sea. Our results showed that (1) the beta diversity values ranged from 0.2 to 0.84 (0.5 average), and turnover dominated. (2) The relative contributions of environmental heterogeneity and dispersal limitation to beta diversity varied seasonally, wherein former dominated in summer and winter, latter dominated in spring and autumn. (3) Hydrologic distance, pH, alkalinity, and total nitrogen were the crucial factors shaping the beta diversity pattern. This study detailed the temporal variation of the relative roles of environmental heterogeneity and dispersal limitation in shaping the patterns of phytoplankton communities, which may reflect the dynamical nature of ocean, characterized by seasonal variation in wind and hydrology. It also clarified the intrinsic linkage between these two processes in the ocean, which provides a novel insight to understanding the ocean biogeography and informs decision making for area‐based marine biodiversity conservation.

Investigating an extreme meteo-oceanographic event in the southern Brazil from in situ observations and modeling results

In March 2016, the passage of a cold front on the southern coast of Brazil generated extreme meteo-oceanographic conditions along the southern Brazilian coast. This work investigates the wave field evolution during this period from in situ observations and numerical modeling. The observations were obtained from high-frequency measurements performed in four sites along the coastline (Santos, Tramandaí, Rio Grande, and Cassino). The wavefield simulations were performed by coupling the Global Forecast System (GFS) reanalysis and the WAVEWATCH-III (WW3) ocean wave model. In a synoptic analysis was observed that not only the cold front caused the high wave in the area, but the interaction between the front post-high-pressure center and a low-pressure center generated a substantial pressure gradient area along the Brazilian coast with winds between 17.1 and 20.7 m s−1 reaching up to 24.4 m s−1. Model estimates confirm the presence of high waves between 6.0 and 6.5 m on the Southern coast of Brazil. Also, in the adjacent deep waters of the South Atlantic Ocean, highly simulated waves reached significant wave heights of 9 m. An analysis of the model input wind indicates that the GFS winds represented very well the trends and evolution of the wind registered by ocean buoys, with a small phase error. The t-test shows no significant differences in any buoys, with p-value = 0.73 and p-value = 0.78, with a significance level of 0.05.The best WW3 domain identified to simulate the wavefield off the coast of Southern do Brazil was 70°W - 4°W longitude and 55°S - 13°S latitude. Two buoys and two ondographic records in the area were used to evaluate the simulations in shallow water. In contrast, a reanalysis with satellite data assimilation was used to compare the simulations. In shallow water, the results for significant height of Wind and Swell Waves (SWH) show how the WW3 model slightly advances the maximum SWH time in relation to the buoys and ondographs records. This maximum SWH simulated by WW3 is in correspondence with the maximum GFS and records wind. The WW3 model underestimated the maximum SWH compared to the maximum buoys recorded and overestimated the maximum SWH compared to the maximum ondographs recorded. The Peak Period (Tp) simulations also showed an underestimate by the model in the two buoys and two ondograph locations. The BIAS distribution showed low values of the SWH in deep water between -1.2 m and 1.2 m. In general, in each analysis carried out, the t-test showed that there are no significant differences between the SWH and Tp simulated and the SWH and Tp records.In the analysis of the directions, it was observed that the strongest winds were recorded from the E direction for both Rio Grande (above 18 m s−1) and Santos (12-15 m s−1) buoys with frequency values of 27.8% and 12% respectively. As a reflection of the wind, predominant directions of E-SE waves were observed with high-frequency values in the Rio Grande (43.1%), Santos (54.2%), Cassino (67.4%), and Tramandaí (100%) records. The presence of waves with Tp (less than 12s) was observed in the records of buoys and wave gauges related to wind-wave. Only in the Santos buoy were observed waves with Tp higher than 12s (swell). The model showed a difference of 22.5° between the recorded wind and wave roses, and 45° between the recorded wind roses and the wave rose.

Ichthyofauna of the Fresh and Brackish Waters of Russia and Adjacent Areas: Annotated List with Taxonomic Comments. 2. Order Cypriniformes, Suborders Catostomoidei, Cobitoidei and Cyprinoidei

This paper is the second part of the “Ichthyofauna of the Fresh and Brackish Waters of Russia and Adjacent Areas: Annotated List with Taxonomic Comments”, which we started in 2022 based on a critical analysis of scientific publications of the last 200 years, and on the data of the author’s research. The current paper includes all currently known fishes of the order Cypriniformes of Russia and adjacent waters, represented by three suborders Catostomoidei, Cobitoidei and Cyprinoidei, comprising ten families, 64 genera and 177 species. The most specious families were the Leuciscidae (59 species/33.3% of all species), Gobionidae (35/19.8%) and Xenocyprididae (23/13.0%), which together represent just over 66% the total cypriniform species. Fourteen of the studied species (24.7% of all cyprinids in Russia) are introduced species, 21 species (11.9%) are endemic; 32 species (18.1%) are recorded from Russia for the first time. In relation to the habitat, 131 species live and breed exclusively in fresh waters, 31 species are of freshwater origin, but can also tolerate slightly brackish waters, ten species are represented by anadromous forms (all with residential populations), and three species are amphidromic, capable of live and reproduce both in brackish water and in freshwater. According to the IUCN criteria, the majority of fish are classified as Least Concern (135 species/76.3%), but two species, Cobitis taurica and Gobio tauricus, are Critically Endangered.

Mangrove Restoration and Conservation Effort in Niger Delta Used as Carbon Offset Option

_ This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 207725, “Mangrove Restoration and Conservation as a Carbon Offset Option: a Case Study in the Niger Delta Region,” by Gustavo C.D. Estrada, Jason Sali, and Patrizio Piras, Eni, et al. The paper has not been peer reviewed. _ Mangroves have gained attention as a carbon offset option because of their high carbon-storage capacity and diverse social and environmental benefits. Carbon stock in mangroves is approximately four times higher than in terrestrial forests and contributes to almost 10% of the global terrestrial carbon pool. In 2017, the Nigerian Agip Oil Company (NAOC) launched an initiative to restore mangroves to promote social and biodiversity benefits while contributing to offsetting its greenhouse-gas (GHG) emissions. The complete paper details the methodology and results of this initiative. Introduction Mangroves are coastal ecosystems mainly composed of typical tree and shrub plant species possessing adaptations to unstable, low-oxygen soil; high-salinity water; and frequent submersion. Fauna equally adapted to the unique environmental conditions observed in the mangroves also are considered part of the ecosystem. Mangrove forests are recognized globally to be of extreme ecological, economic, social, and cultural importance because of the variety of goods and services they provide. Some of these include the protection of the coastline from the energy of the winds and waves and conservation of fishing and biodiversity in coastal and adjacent estuarine waters. The literature suggests that more than 812,000 ha of mangrove areas, spread over 106 countries or territories, show potential for restoration. Furthermore, mangroves have been lost globally at a rate of 1–2%/year, which may account for an annual emission of approximately 0.09–0.45 GtCO2eq/year that could be avoided through conservation. Because the dispersion of mangroves propagules (seeds that have germinated while attached to the mother plant) is driven by ocean and estuarine currents, natural recolonization can occur and mangroves recover successfully by secondary succession during a period of 10–15 years if conditions are ideal. However, ecosystem function may take more than a century to be fully reinstated. Understanding the autoecology, hydrological patterns, and factors impairing natural regeneration is key for a successful restoration project. Several examples exist of restoration programs that were unsuccessful for, among other problems, having failed to acquire these key prerestoration data. During the last 10–15 years, a community-based ecological mangrove restoration effort has emerged based on the recognition that ecological science is not enough to assure successful restoration of mangroves and that social and economic issues must also be integrated.

Tidewater glaciers as “climate refugia” for zooplankton-dependent food web in Kongsfjorden, Svalbard

With climate warming, many tidewater glaciers are retreating. Fresh, sediment-rich sub-glacial meltwater is discharged at the glacier grounding line, where it mixes with deep marine water resulting in an upwelling of a plume visible in front of the glacial wall. Zooplankton may suffer increased mortality within the plume due to osmotic shock when brought in contact with the rising meltwater. The constant replenishment of zooplankton and juvenile fish to the surface areas attracts surface-foraging seabirds. Because access to other feeding areas, such as the marginal ice zone, has become energetically costly due to reduced sea-ice extent, glacial plumes may become increasingly important as “climate refugia” providing enhanced prey availability. Here, we investigated zooplankton concentrations within the plume and adjacent waters of four tidewater glaciers in Kongsfjorden, Svalbard, in early August 2016 and late July 2017. Our aim was to compare the zooplankton composition, abundance, and isotopic signatures within the plumes to those in adjacent fjord and shelf waters. Our hypothesis was that the plumes resulted in increased zooplankton mortality through osmotic shock and increased prey availability to predators. The mortality due to osmotic shock in the glacial plume was low (<5% dead organisms in samples), although slightly higher than in surrounding waters. This indicates that plumes are inefficient “death traps” for zooplankton. However, the high abundance and biomass of zooplankton within plume areas suggest that the “elevator effect” of rising glacial water supplies zooplankton to the sea surface, thereby enhancing prey availability for surface-feeding seabirds. Thus, our study provides evidence that glacial plumes are important as “climate refugia” for foraging seabirds. Stable isotope signatures showed that the glacial bay zooplankton and fish community represent a distinct isotopic niche. Additionally, zooplankton mortality associated with the plume estimated over 100-days of melt season supports a flux of 12.8 tonnes of organic carbon to benthic communities in the glacial bays. Benthic scavengers, such as Onisimus caricus and Anonyx nugax, were abundant in the glacial bay, where they feed on sinking organic matter.

Modal content of typhoon-induced near-inertial waves around the East China Sea

Recent studies show that typhoon-induced near-inertial waves (NIWs) exhibit different modal content in the shallow and deep regions, whereas the underlying mechanism has not been fully understood. Based on a three-dimensional numerical model, we simulate the NIWs induced by two typhoons (Songda and Meari in 2011) in the East China Sea and its adjacent deep waters in the northwest Pacific Ocean. Although the near-inertial kinetic energy induced by the two typhoons has different intensity and spatial distribution, the modal content of NIWs induced by them shares a common characteristic: In the shallow regions (water depth smaller than 200 m), the NIWs are mainly dominated by mode-1; whereas in the deep regions (water depth larger than 200 m), the NIWs are dominated by higher modes (mode-2 to mode-5). Different mechanisms are found to account for the different modal content in shallow and deep regions. The dominance of higher-mode wind forcing is the cause for the dominance of higher-mode NIWs in the deep regions. The two-layer-structure stratification is the cause for the dominance of mode-1 NIWs in the shallow regions.

Dissolved Oxygen Prediction Model for the Yangtze River Estuary Basin Using IPSO-LSSVM

Water ecology has always been key to environmental protection, and the combination of human activities and natural factors has caused eutrophication in the Yangtze estuary and adjacent waters. Among them, dissolved oxygen (DO) concentration is the key indicator to judge the quality of water. Firstly, using principal component analysis (PCA) to determine the number of parameters affecting dissolved oxygen concentration, the least squares support vector machine (LSSVM) prediction model with improved particle swarm optimization (IPSO) is proposed to be applied to the dissolved oxygen prediction in Shanghai’s Yangtze River basin through the data-driven modeling approach and the regression prediction capability of the neural network. Eight parameters of water temperature (WT), pH, potassium permanganate (KMnO4), ammonia nitrogen (NH4+-N), total phosphorus (TP), total nitrogen (TN), conductivity (Cond), and nephelometric turbidity unit (NTU) are selected as model inputs in the published public data, and the output is the dissolved oxygen concentration. The optimal combination of model parameters is found according to the IPSO algorithm, which effectively overcomes the parameter selection problem of regular support vector machines (SVM). The mean absolute error (MAE), root mean square error (RMSE), mean absolute percentage error (MAPE), and correlation coefficients of the evaluation indexes of this model (R2) are 0.1702, 0.2221, 0.0267, and 0.9751, respectively. Compared with other similar data driven models, this model has improved model accuracy and stability in predicting DO concentrations in the estuary, and thus it provides technical support for assessing and monitoring offshore water quality.

Persistence of Antibiotic Resistance Genes Varies with Particle Size and Substrate Conditions in Recirculating Streams.

Antibiotic resistance (AR) determinants are enriched in animal manures, a significant portion of which is land-applied as a soil amendment or as fertilizer, leading to potential AR runoff and microbial pollution in adjacent surface waters. To effectively inform AR monitoring and mitigation efforts, a thorough understanding and description of the persistence and transport of manure-derived AR in flowing waters are needed. We used experimental recirculating mesocosms to assess water-column removal rates of antibiotic resistance genes (ARGs) originating from a cow manure slurry collected from a dairy farm. We quantified the effect of three benthic (i.e., bottom) substrate variations and particle sizes of manure slurry on water column removal rates. Overall, we observed variation in ARG behavior across substrate treatments and particle sizes. For ARGs associated with small particles, removal rates were higher in mesocosms with a substrate. tetW was typically removed at the highest rates across particle size and treatment, followed by ermB and blaTEM. Our data suggests that both substrate character and particle size exert control on the fate and transport of ARGs in surface waters, laying the foundation for future research in this area to establish a predictive framework for AR persistence and fate in flowing waters.

Eastern banded killifish (Fundulus diaphanus diaphanus) in Lake Michigan and connected watersheds: The invasion of a non-native subspecies

Biological invasions can produce severe ecological impacts at both large spatial scales between distantly related species and also smaller spatial scales between conspecifics. We investigated here a potential intraspecific invasion within Lake Michigan and adjacent waters. Banded killifish (Fundulus diaphanus) experienced population increases and spread into novel habitats over recent decades in this region, but managers and policy makers were uncertain if these fish were native western banded killifish (F. d. menona) or instead an invasion by non-native eastern banded killifish (F. d. diaphanus). We applied mitochondrial DNA (mtDNA) barcoding and population genetic analyses to investigate the identity of these fish. We found that new banded killifish populations were the eastern subspecies, including mtDNA haplotypes from the remote mid-Atlantic region, suggesting some introductions from anthropogenic pathways (e.g., live bait trade) rather than only spread from connected, downstream waters (e.g., Lake Erie). Further, population genetic analyses identified eastern banded killifish in our focal region as having low genetic diversity relative to their native range, and relative to western banded killifish populations. Lastly, we found non-native eastern banded killifish were associated with Lake Michigan and connected waters, rather than isolated kettle lakes, and primarily occurred at clearer sites potentially affected by dreissenid mussel invasions. More research is needed on the causes and consequences of eastern banded killifish invasions in Lake Michigan and adjacent waters, including an emphasis on their risk to the conservation of western banded killifish.

Natural iron fertilization by shallow hydrothermal sources fuels diazotroph blooms in the ocean.

Iron is an essential nutrient that regulates productivity in ~30% of the ocean. Compared with deep (>2000 meter) hydrothermal activity at mid-ocean ridges that provide iron to the ocean's interior, shallow (<500 meter) hydrothermal fluids are likely to influence the surface's ecosystem. However, their effect is unknown. In this work, we show that fluids emitted along the Tonga volcanic arc (South Pacific) have a substantial impact on iron concentrations in the photic layer through vertical diffusion. This enrichment stimulates biological activity, resulting in an extensive patch of chlorophyll (360,000 square kilometers). Diazotroph activity is two to eight times higher and carbon export fluxes are two to three times higher in iron-enriched waters than in adjacent unfertilized waters. Such findings reveal a previously undescribed mechanism of natural iron fertilization in the ocean that fuels regional hotspot sinks for atmospheric CO2.

Monitoring suspended sediment concentration in the Yellow River Estuary from 1984 to 2021 using landsat imagery and Google Earth Engine

ABSTRACT The transport of suspended sediment in estuaries affects the erosion and deposition of estuaries and changes in landform patterns, and it has a profound impact on primary productivity and ecosystem regulation in estuaries. It is of great value for coastal construction and environmental monitoring to study the surface suspended sediment concentration (SSC) in estuaries and adjacent waters. Using 2355 Landsat 5/7/8 satellite images from the Google Earth Engine, the SSC in the surface layer of the Yellow River Estuary from 1984 to 2021 was studied. The results showed that from 1984 to 2021, the SSC declined by more than 30%. The Xiaolangdi Dam and Water and Sediment Regulation Scheme have affected the sediment transport and runoff of the Yellow River, which can explain more than 40% of the SSC in the buffer area of the estuary and have a close relationship with the inter-monthly changes in SSC. The diversion of estuaries and circulation to the transport of suspended sediment have largely affected the changes in nearshore SSC, including the spatial patterns and temporal variations in SSC. Wave changes caused by wind speed on the sea surface can explain the inner-annual changes in SSC in Laizhou Bay and southern Bohai Bay. From January to February, the area of high concentration zones (100 mg L−1≤SSC) accounts for more than 10%, higher than in other months, and re-suspension of sediment caused by wind is the main reason for the increase in SSC.

Book review. The molluscs of Gulf of Mannar, India and adjacent waters: A fully illustrated guide

Book review. The molluscs of Gulf of Mannar, India and adjacent waters: A fully illustrated guide

Metabarcoding Extends the Distribution of Porphyra corallicola (Bangiales) into the Arctic While Revealing Novel Species and Patterns for Conchocelis Stages in the Canadian Flora

Porphyra corallicola was described based on a filamentous red alga inadvertently introduced into culture from a crustose coralline alga. This species is known only in its sporophyte (Conchocelis) stage, being possibly asexual and lacking the charismatic and “collectable” gametophyte stage. Consequently, little is known of its range and distribution. Taxon-targeted metabarcoding was explored as a pathway to gain insights into the vertical (intertidal versus subtidal) and biogeographical distribution of this species, as well as to assess host diversity. We also wanted to ascertain if other species occur in only the Conchocelis stage in the Canadian flora. Primers targeting a short (521 bp) region of the plastid rbcL gene in the Bangiales were used to screen DNA from 285 coralline crusts collected throughout Canada and adjacent waters. In addition to confirming the presence of P. corallicola in the Bay of Fundy, this species was recovered from coralline crusts along the coast of Nova Scotia (n = 1) and in the low Arctic (Labrador; n = 2), greatly extending its range and suggesting it is a cold-water taxon. We have confirmed its presence in both the low intertidal and subtidal (to 10 m), and its occurrence in three different coralline species, suggesting that it lacks host specificity. In total, nine genetic groups of Bangiales were uncovered in our survey, six matching entries currently in GenBank and three apparently novel genetic groups—two from the northeast Pacific and one from the low Arctic. Notable host and ecological patterns are discussed. This method, when further developed, will facilitate the study of Conchocelis stages in nature, which will greatly enhance ecological knowledge of bangialean species.

Effect of Tide Level Change on Typhoon Waves in the Taiwan Strait and Its Adjacent Waters

In recent years, most research on typhoons in the Taiwan Strait and its adjacent waters has focused on simulating typhoon waves under the influence of wind fields. In order to study the influence of tidal level changes on typhoon waves, a numerical model was established in the Taiwan Strait based on the third-generation ocean wave model SWAN. The simulation results of the tide level during the corresponding typhoon landing time were incorporated into the model to optimize its performance. Subsequently, the wave height of the typhoon landing at the lowest tide level was compared with that at the highest tide level. This comparison serves as a reference and warning for ocean engineering, highlighting the hazards of the typhoon landing at high tide. The simulation results were verified and analyzed using the measured data of significant wave heights and wind speeds when typhoons Mekkhala (2006) and Maria (0607) approached. The results show that after optimization, the relative error of the significant wave peak is reduced. Furthermore, there has been a decrease in the maximum wind speed, bringing it closer to the measured value. These improvements signify enhanced model accuracy. The tide level has a great influence on the typhoon wave, and the tide level height at the time of the typhoon landing is positively correlated with the significant wave height of the waves generated by the typhoon. When the typhoon’s landing time coincides with the high tide level, the resulting waves are significantly higher, reaching up to 0.71 m. This has a substantial impact on the safety of marine structures, particularly breakwaters.

Biologically Important Areas II for cetaceans within U.S. and adjacent waters – Gulf of Alaska Region

We delineated and scored Biologically Important Areas (BIAs) for cetacean species in the Gulf of Alaska region. BIAs represent areas and times in which cetaceans are known to concentrate for activities related to reproduction, feeding, and migration, and also the known ranges of small and resident populations. This National Oceanic and Atmospheric Association (NOAA)-led effort uses structured expert elicitation principles to build upon the first version of NOAA’s BIAs for cetaceans. Supporting evidence for these BIAs came from aerial-, land-, and vessel-based surveys; satellite-tagging data; passive acoustic monitoring; Indigenous knowledge; photo-identification data; and/or prey studies. A total of 20 BIAs were identified, delineated, and scored for six species: beluga whale (Delphinapterus leucas), fin whale (Balaenoptera physalus), gray whale (Eschrichtius robustus), humpback whale (Megaptera novaeangliae), North Pacific right whale (Eubalaena japonica), and sperm whale (Physeter macrocephalus). Of the 20 total BIAs, there were two small and resident populations, one migratory, and 17 feeding areas; no reproductive BIAs were identified. An additional five watch list areas were identified, a new feature to the second version of BIAs. In addition to more comprehensive narratives and maps, the BIA II products improve upon the first version by creating metadata tables and incorporating a scoring and labeling system which improves quantification and standardization of BIAs within and across regions. BIAs are compilations of the best available science and have no inherent regulatory authority. They have been used by NOAA, other federal agencies, and the public to support planning and marine mammal impact assessments, and to inform the development of conservation measures for cetaceans.

Trends in the Socio-Economic Development of the Arctic Zone of the Russian Federation and the Importance of Cruise Tourism on the Northern Sea Route

The article discusses the prospects of socio-economic development of the territory of the Arctic zone of the Russian Federation and the role of the organization of Arctic tourism on the Northern Sea Route (NSR). Among all the northern countries of the world, Russia has the longest coastline in the Arctic seas and the largest sector of the adjacent shelf and waters of the seas of the Arctic Ocean (SLO). It is shown that, in comparison with neighboring Arctic countries, the potential of the development of tourist space and the development of Arctic tourism in the Russian Federation is far from being fully used. The current possibilities and prospects of using the nuclear icebreaker fl eet of the Russian Federation for the development of the Arctic zone of the Russian Federation (AZRF) are discussed. The prospects of improving the infrastructure of ports in the northern polar regions and the possibilities of developing Arctic cruise tourism on the NSR route are considered.