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Hydra is known for its natural occurrence, anatomical simplicity, intricate physiology, regenerative capacity, and ease of maintenance and manipulation in laboratory environments. It has proven to be a valuable model organism in various disciplines. Its applications range from developmental biology, stem cell research, animal physiology to environmental toxicology including ecotoxicology. The sensitivity of Hydra to a variety of environmental stressors and chemical agents such as metals, nanomaterials, and toxic organic compounds provides valuable insights into physiological mechanisms affected by environmental stressors and pollution, and Hydra can be of great use in environmental monitoring. Furthermore, since green Hydra lives in a symbiotic relationship with unicellular photoautotrophic algae, it is a suitable model organism for symbiosis research. Recently, it has become a popular model in holobiont research. The adaptability and importance of Hydra also extends to aquatic science and aquatic ecology, particularly in the context of monitoring and water pollution. Since the 1980s, Hydra has been increasingly used in various fields of research and has established itself as an important versatile model organism in numerous scientific studies. Hydra also represents an outstanding model in the fields of education and STEM. Hydra continues to be an important model in the 21st century, contributing significantly to our understanding of the biology of water and advancing freshwater research, and possibly finding its way to regenerative medicine and tumor pathobiology research. [ABSTRACT FROM AUTHOR]

Kempnyia (Plecoptera: Perlidae) is an endemic genus of Brazilian stoneflies that has 36 valid species and is distributed primarily in the Atlantic Forest and the mountainous areas of Central Brazil, particularly in Goiás and Tocantins states. Despite being the Brazilian genus with the most DNA sequences available on GenBank, integrative studies on the genus began only recently, in 2014. In this context, herein we studied the morphology and molecular data of Kempnyia specimens deposited in the Aquatic Biology Laboratory (UNESP, Assis) and the Entomology Museum of the Federal University of Viçosa (UFVB, Viçosa) collections. For the integrative approach adopted, in addition to studying the specimens morphologically, we used sequences of the COI mitochondrial gene combined with the following species delimitation methods: Automatic Barcode Gap Discovery (ABGD), both primary (ABGDp) and recursive (ABGDr) partitions; Assemble Species by Automatic Partitioning (ASAP); Poisson Tree Processes (PTP) and the Bayesian implementation of the Poisson Tree Processes (bPTP). As a result, we provided 28 new COI sequences of 21 species and support the description of four new species, namely, K. guaranisp. nov., K. tupiniquimsp. nov., K. unasp. nov., and K. zwickiisp. nov., consequently increasing the known diversity of the genus to 40 species. We also discuss the morphological variations observed in other species of the genus and provide several new geographic records. Therefore, our study brings new insights into the values of intra- and interspecific molecular divergence within Kempnyia, serving as a basis for new studies. [ABSTRACT FROM AUTHOR]

This article discusses a study on humpback whale vocalizations in a mid-latitude, winter feeding ground in Virginia. The researchers were unable to determine the sex of the whale, but they found that it vocalized for a significant amount of time, producing 11 distinct call types. They also identified patterns and themes in the whale's vocalizations, suggesting the presence of song fragments. The researchers hypothesize that the tagged whale was a juvenile male practicing singing behavior. The article also highlights the threat of vessel strikes to humpback whales, particularly in the U.S. Atlantic Coast, where ship traffic is increased. The researchers suggest that the whale's passive, head-down orientation during vocalizations may increase its vulnerability to ship strikes. Overall, this study contributes to our understanding of humpback whale behavior and the risks they face in their feeding grounds. [Extracted from the article]

The present study provides new insight into the key aspects of the early formative period of the ecosystem concept in aquatic ecology. Raymond Lindeman's trophodynamics is known to be a starting point for the development of the modern concept of ecosystem. The trophodynamic approach in ecology was proposed by Lindeman in his widely cited paper of 1942. Lindeman's views are analyzed in comparison with the contemporary production studies in aquatic ecology. It is shown that a similar theoretical system has been proposed in the USSR at the end of the 1930s by Georgiy G. Vinberg. He introduced the concept of biotic balance based on the wide appraisal of the dark and light bottles method. The study shows that both Lindeman's trophodynamics and Vinberg's concept of biotic balance relied on an energy-based approach in considering the wholeness of a water body. The two scientists, however, differed in several important aspects concerning the interpretation of the role of living organisms. The holistic interpretation of ecosystem by Lindeman and Vinberg can be seen as part of the dilemma between physicalism and organicism. At the same time, the main emphasis in the concepts of both Vinberg and Lindemann was on the primary production component, a feature that was common to the first holistic systems in production hydrobiology (e.g., E. Naumann's regional limnology). It is clear that modern problems of aquatic ecology should be addressed from the perspective of the organismocentric understanding of the ecosystem, but undoubtedly at the new level of development of this view. [ABSTRACT FROM AUTHOR]

The essay describes how a combination of scaling theory from percolation, that relates pore scale flow and transport through catchment scales to global scales (bottom‐up), as well as water fluxes to soil formation and vegetation growth, can be used to support an accurate ecological optimization that (top‐down): solves the central problem of hydrology, that is., "the water balance," and generates critically important derived quantities, namely streamflow response to climate change, net primary productivity, and plant species richness. Moreover, the essay describes how this particular theoretical approach came to be designed and how it, in retrospect, fits in with the vision of the Committee on Opportunities in the Hydrologic Sciences which met 34 years ago to formulate a research, teaching, and infrastructure guide for the community, and "rebrand our science as a geoscience." Finally, it demonstrates how the research satisfies the present desires of the community to unite Darwinian and Newtonian scientific methods in the solution of this central problem and how it relates to present research directions in the fields of hydrologic sciences and ecology. [ABSTRACT FROM AUTHOR]

The biophysics of water, has been debated over more than a century. Although its importance is still underestimated, significant breakthroughs occurred in recent years. The influence of protein condensation on water availability control was documented, new findings on water-transport proteins emerged, and the way water molecules rearrange to minimize free energy at interfaces was deciphered, influencing membrane thermodynamics. The state of knowledge continued to progress in the field of deep-sea marine biology, highlighting unknown effects of high hydrostatic pressure and/or temperature on interactions between proteins and ligands in extreme environments, and membrane structure adaptations. The role of osmolytes in protein stability control under stress is also discussed here in relation to fish egg hydration/buoyancy. The complexity of water movements within the cell is updated, all these findings leading to a better view of their impact on many cellular processes. The way water flow and osmotic gradients generated by ion transport work together to produce the driving force behind cell migration is also relevant to both marine biology and cancer research. Additional common points concern water dynamic changes during the neoplastic transformation of cells and tissues, or embryo development. This could improve imaging techniques, early cancer diagnosis, and understanding of the molecular and physiological basis of buoyancy for many marine species. [ABSTRACT FROM AUTHOR]

Queen triggerfish Balistes vetula is an important reef-associated species for commercial fisheries in the U.S. Caribbean. It exhibits a relatively unique reproductive strategy as a nesting benthic spawner, investing substantial energy in territorial defense, building and maintaining nests, and caring for fertilized eggs during the reproductive season. Prior to this study, no comprehensive life history information existed in the literature for queen triggerfish. This study provides the first comprehensive documentation of age, growth, size/age at sexual maturity, reproductive seasonality, and reproductive output for a Balistes species in the Caribbean. From 2013 to 2023, we collected 2190 fish samples from fisheries-dependent and -independent sources from the waters of Puerto Rico and the U.S. Virgin Islands. Fish ranged from 67 to 477 mm fork length (FL). We documented that queen triggerfish is sexually dimorphic with males attaining larger mean sizes-at-age compared to females and the species is characterized by a moderately young age at median sexual maturity (A50 = 3.3 y). The maximum age for our U.S. Caribbean samples was 23 y based on increment counts from otoliths. Spawning season encompassed the months of December to August in the region, and female spawning frequency ranged from an estimated 2 to 84 times per year; female spawning frequency increased with increasing size and age of fish. We documented that commercial fishers in the U.S. Caribbean mainly target "plate-size" individuals, defined in our study as 235–405 mm FL, which appears to act as a self-imposed slot size range limit and results in the fishery not removing individuals in the smallest and largest size groups at high rates. The percentage of immature fish from fisheries-dependent sources was close to 0 (0.8%). Commercial fishing for queen triggerfish in the region currently appears to be sustainable, but monitoring of the population should continue. [ABSTRACT FROM AUTHOR]

This article examines the potential impact of climate change on the distribution of the Redbelly Tilapia in Iraq. The study finds that northern Iraq is the most suitable habitat for the species and emphasizes the need for proactive measures to prevent its establishment in these regions. The research provides actionable insights for conservation efforts and informs policy decisions to preserve native ecosystems. The article also highlights the importance of collaborative efforts among neighboring countries to address the challenges of invasive species spread. Additionally, the study suggests the need to balance conservation and aquacultural benefits when selecting suitable habitats for aquacultural facilities. [Extracted from the article]

Copyright of Journal of Anatolian Environmental & Animal Science is the property of Bulent Verep and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Anatolian Environmental & Animal Science is the property of Bulent Verep and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This article explores the cultural evolution of humpback whale songs in the South Atlantic, specifically focusing on changes observed in Brazil between 2017 and 2018. The study reveals a significant shift in the complexity of the songs, suggesting a cultural revolution within the humpback whale population. The authors propose that these revolutions are a result of cultural exchange between different populations during the nonbreeding season, facilitated by the lack of physical barriers in the Southern Hemisphere. The research emphasizes the importance of acoustic interactions in understanding the dynamics of humpback whale songs and highlights the need for further study in this area. [Extracted from the article]

Summary: Although diverse microorganisms can remove ammonium and nitrate simultaneously, their metabolic mechanisms are not well understood. Paracoccus denitrificans R-1 showed the maximal NH4+ removal rate 9.94 mg L−1·h−1 and 2.91 mg L−1·h−1 under aerobic and anaerobic conditions, respectively. Analysis of the nitrogen balance calculation and isotope tracing experiment indicated that NH4+ was consumed through assimilation. The maximal NO3− removal rate of strain R-1 was 18.05 and 19.76 mg L−1·h−1 under aerobic and anaerobic conditions, respectively. The stoichiometric consumption ratio of acetate to nitrate was 0.902 and NO3− was reduced to N2 for strain R-1 through 15NO3− isotopic tracing experiment, which indicated a respiratory process coupled with the oxidation of electron donors. Genomic analysis showed that strain R-1 contained genes for ammonium assimilation and denitrification, which effectively promoted each other. These findings provide insights into microbial nitrogen transformation and facilitate the simultaneous removal of NH4+ and NO3− in a single reactor.

Summary: The phytoplankton Phaeocystis globosa plays an important role in sulfur cycling and climate control, and can develop harmful algal blooms (HABs). Here we report a chromosome-scale reference genome assembly of P. globosa, which enable in-depth analysis of molecular underpinnings of important ecological characteristics. Comparative genomic analyses detected two-rounds of genome duplications that may have fueled evolutionary innovations. The genome duplication may have resulted in the formation of dual HiDP and LoDP dimethylsulphoniopropionate (DMSP) biosynthesis pathways in P. globosa. Selective gene family expansions may have strengthened biological pathways critical for colonial formation that is often associated with the development of algal blooms. The copy numbers of rhodopsin genes are variable in different strains, suggesting that rhodopsin genes may play a role in strain-specific adaptation to ecological factors. The successful reconstruction of the P. globosa genome sets up an excellent platform that facilitates in-depth research on bloom development and DMSP metabolism.

Summary: Oyster reefs are hotspots of denitrification mediated removal of dissolved nitrogen (N), however, information on their denitrifier microbiota is scarce. Furthermore, in oyster aquaculture, triploids are often preferred over diploids, yet again, microbiome differences between oyster ploidies are unknown. To address these knowledge gaps, farmed diploid and triploid oysters were collected over an annual growth cycle and analyzed using shotgun metagenomics and quantitative microbial elemental cycling (QMEC) techniques. Regardless of ploidy, Psychrobacter genus was abundant, with positive correlations found for genes of central metabolism, DNA metabolism, and carbohydrate metabolism. MAGs (metagenome-assembled genomes) yielded multiple Psychrobacter genomes harboring norB, narH, narI, and nirK denitrification genes, indicating their functional relevance within the eastern oysters. QMEC analysis indicated the predominance of carbon (C) and nitrogen (N) cycling genes, with no discernable patterns between ploidies. Among the N-cycling genes, the nosZII clade was overrepresented, suggesting its role in the eastern oyster’s N removal processes.

The article discusses a study on evidence of a predatory interaction between a cookiecutter shark (Isistius brasiliensis) and Galapagos fur seals (Arctocephalus galapagoensis) conducted by Andrés Moreira-Mendieta et al., published in the journal Aquatic Mammals. It highlights the occurrence of a fresh circular wound on a fur seal caused by a cookiecutter shark, emphasizing the potential impact of such sublethal predation events on the fitness of the prey species.

This text discusses the artwork and performances of Agnes Questionmark, focusing on two specific pieces: Sirenomelia and TRANSGENESIS. Sirenomelia explores the concept of anomaly through the fusion of human and fish characteristics, challenging traditional notions of gender and celebrating bodily deformities. TRANSGENESIS imagines a new form of evolutionism, where humans hybridize with animals to create a new species, questioning the taxonomic order and emphasizing interconnectedness with other beings. The performances aim to provoke thought and open minds, encouraging a reevaluation of societal norms and relationships with nature. The text also references English Aestheticist art from the 1870s, which explored queer ecologies and plant-human entanglements. [Extracted from the article]

High mountain areas are especially vulnerable to global warming, as they experience faster temperature changes than lowlands in a climate change context. Notably, increased temperatures and frequency of extreme flooding and droughts, and the consequent decrease in ice cover and water availability fluctuations, will induce important physical changes in alpine freshwater systems. Thus, assessing thermal limits and exploring overwintering strategies of aquatic alpine insects is pivotal to understanding how aquatic communities of high‐mountain fresh waters will respond to climate change. However, knowledge on these topics is still scarce for aquatic alpine insects.Here, the thermal biology of adults of five diving beetle species from alpine lakes located in the Sierra Nevada mountain range (southern Iberia) was studied. Cold tolerance was measured estimating the supercooling point (SCP), lower lethal temperature (LLT), tolerance to ice enclosure and to submersion, whereas heat tolerance was assessed from the heat coma temperature and upper lethal temperature.All of the species survived ice enclosure for 3 h. Furthermore, three of the studied species had SCPs higher than their LLTs, suggesting that they could be freeze‐tolerant. All species except Agabus nevadensis also were tolerant to submersion, which could be a key adaptation for overwintering underwater below the ice cover as adults, reducing risk from freezing conditions in the air. The species did not differ significantly in their upper thermal limits, which were similar to those of other dytiscids from lower altitudes.Overall, our results suggest that increasing temperatures is not expected to be the most important threat for the water beetle populations in Sierra Nevada, but rather the colonisation of alpine lakes by lowland dytiscids in a warmer climate scenario. [ABSTRACT FROM AUTHOR]

Summary: Alpine lakes play pivotal roles in plateau hydrological processes but are highly sensitive to climate change, yet we lack comprehensive knowledge of their multitrophic biodiversity patterns. Here, we compared the biodiversity characteristics of diverse taxonomic groups across water depths and in surface sediments from a freshwater lake and a hypersaline lake on the northwestern Tibetan Plateau. Using multi-marker environmental DNA metabarcoding, we detected 134 cyanobacteria, 443 diatom, 1,519 invertebrate, and 28 vertebrate taxa. Each group had a substantially different community composition in the two lakes, and differences were also found between water and sediments within each lake. Cooccurrence network analysis revealed higher network complexity, lower modularity, and fewer negative cohesions in the hypersaline lake, suggesting that high salinity may destabilize ecological networks. Our results provide the first holistic view of Tibetan lake biodiversity under contrasting salinity levels and reveal structural differences in the ecological networks that may impact ecosystem resilience.

Summary: Gametogenesis drives the maturation of germ cell precursors into functional gametes, facilitated by interactions with the niche environment. However, the molecular mechanisms, especially in invertebrates, remain incompletely understood. In this study, the gonadal microenvironment and gametogenic processes in the Pacific oyster, a model for diffuse gonadal organization and periodic gametogenesis, are investigated. We combine single-nucleus RNA-seq and bulk RNA-seq to analyze gonadal microenvironments in oysters. Twenty-three male and nineteen female gonadal cell clusters are identified, revealing four male and three female germ cell types, alongside follicular cells in females and Sertoli/Leydig cells in males. The NOTCH and BMP (bone morphogenetic protein) signaling pathways play a significant role in the male germline niche, suggesting similarities with mammalian germ cell microenvironment. This study offers valuable insights into germ cell developmental transitions and microenvironmental characteristics.

Because of ectothermy and the high permeability of their skin, the thermal biology and water balance of anuran amphibians are highly influenced by variations in environmental temperature and water availability. Seasonal variation in these climatic variables are often followed by concurrent adjustments in frogs' thermal biology and water balance. We investigated seasonal variation in the thermal biology and water balance of snouted treefrogs, Scinax fuscovarius (Anura, Hylidae), a midsize nocturnal treefrog with continuous activity throughout the year. We measured body temperature when active in the field (Tfield), thermal preference (Tpref) in a thermal gradient in the laboratory, and the minimum and maximum critical temperatures (CTmin and CTmax, respectively). Regarding water balance, we measured rates of evaporative water loss (EWL) and the skin resistance (Rs) to evaporation at three temperatures (15, 25, and 35°C), dehydration tolerance, and rates of water uptake (WU), both at 25°C. Measurements were carried out in the middle of the hot and wet spring–summer and the cold and dry autumn–winter. We found that Tfield, Tpref, dehydration tolerance, and WU were higher in the hot–wet compared to the cold–dry season. Evaporative water loss rates increased with experimental temperature but did not vary seasonally. There was no seasonal variation in thermal tolerance for either CTmax or CTmin. Our data show that S. fuscovarius experience seasonal adjustments in some parameters of their thermal biology and water balance, but not in others. This variation may reflect different levels of plasticity among the sampled variables and quite likely functional compromises between body temperature regulation and water balance. [ABSTRACT FROM AUTHOR]

Factors influencing the distribution and variations of abundance of phytoplankton of dams are yet to be accounted for in Southwest Nigeria. Therefore, the objective of this paper was to evaluate the seasonal distribution and variations of abundance of phytoplankton community in Ikere Gorge Dam, Oyo State, Southwest Nigeria using standard techniques. Data obtained show that a total of 494 microalgal taxa belonging to eight divisions were recorded. Zygnematophyceae comprised 360 taxa (64%), Bacillarophyceae 22 taxa (14%), Chlorophyceae 66 taxa (13%), Cyanophyceae 20 taxa (4%), Dinophyceae 8 taxa (1%), Trebouxiophyceae 13 taxa (2%), Ulvophyceae 3 taxa (0.02%), Xanthophyceae 2 taxa (0.01%). The observations and results confirm hypotheses that phytoplankton abundance varies more between season (wet and dry) than spatially in Ikere gorge dam. No single taxon or a combination of two or three taxa accounted for more than 80% of the phytoplankton abundance. Canonical correspondence analysis revealed DO, TDS, nitrate-nitrogen and water transparency as the major water quality variables driving variation in the composition of plankton communities in the dam. This study showed seasonality is the major factor influencing the diversity and abundance of phytoplankton community through changes in concentrations of DO, nitrates, and phosphate. Ikere Gorge dam showed a strong seasonal variation in physicochemical water quality variables owing to the size of the dam that is not well-mixed, and with long water residence times. This study contributes to understanding the water quality, determinant factors, and drivers of biological communities in dams of tropical regions that are being influenced by anthropogenic activities. [ABSTRACT FROM AUTHOR]

The objective of this research is to assess the breeding value of male individuals and calculate heritability values for body weight and body length at 12 months of age in the rainbow trout population in the Republic of Serbia. The study utilized data on the physical development of trout obtained through the Center for Fisheries and Applied Hydrobiology "Mali Dunav", Experimental Estate "Radmilovac" of the Faculty of Agriculture, University of Belgrade (CEFAH) Breeding Program for rainbow trout in the Republic of Serbia. The fish were raised in individual tanks under tightly controlled conditions at the CEFAH, until they reached 5 months of age. At this point, the fish were marked (with PIT tags Norway) and transferred to commercial fish farms, where monitoring of their production results continued. To estimate the breeding value for body weight and body length of rainbow trout at 12 months of age, we analyzed data collected between 2016 and 2020, which included a total of 2014 individuals. The breeding values were estimated using a sire model. The mixed model incorporated fixed effects (spawning year and sex) and a random effect for the individual sire. The heritability estimate at 12 months of age was 0.44 for body weight, and 0.45 for body length. The breeding values were estimated for 107 sires, with body weight values ranging from −37.83 to +37.83 g and body length values ranging from −14.00 to +14.00 mm. The substantial variation observed within the studied rainbow trout population suggests the potential for further genetic improvement. The high heritability values confirm that further selection can be based on the phenotype. The inclusion of high-quality and validated males in breeding programs will contribute to the enhancement of production characteristics within the existing rainbow trout population in Serbia. [ABSTRACT FROM AUTHOR]

Each dietary analysis method has its own strengths and limitations and provides different perspectives for understanding the trophic biology of aquatic organisms. In this study, we used an integrative, multi-tool approach to comprehensively investigate the dietary differences of eight nominally herbivorous fishes from five feeding guilds in the Nansha Islands (N: 8°51′10°57', E: 112°50′115°35') of the South China Sea. The methods used in this study included 18S rDNA metabarcoding, standard gut content analysis, and stable isotope analysis. DNA metabarcoding revealed diverse algae categories (Ochrophyta, Rhodophyta, and Chlorophyta) in the gut contents of sampled fishes with high taxonomic resolution, and some microscopic and cryptic taxa, such as dinoflagellates and microinvertebrates, were precisely identified. The overlap of 95% prediction isotopic niche remained below 30% between different feeding guilds, and nearly 70% of the 107 genera detected in the gut contents were not shared by two or more fish species or feeding guilds. By combining stable isotope analysis and morphological identification with gut content metabarcoding, we found that the dietary overlap detected by metabarcodng between Ctenochaetus striatus and other fishes may be due to interference from debris of algae or other organisms. While each method has its own limitations in dietary analysis, our study suggests that an integrative, multi-tool approach can remedy the limitations of one method by utilizing the strengths of another. Our results indicate that a wide spectrum of resources on coral reefs could be utilized by different fish species in a complementary manner. [ABSTRACT FROM AUTHOR]

In the European Union, assessments of the quality of the aquatic environment based on aquatic invertebrates are mandatory. Biological methods are supplemented with hydromorphological assessments of watercourses. There are many studies analysing the relationships between aquatic invertebrates and the hydromorphological assessment of the environment by the River Habitat Survey (RHS) method, but thus far, there has been no detailed study including water mites (Acari, Hydrachnidia) and the application of this method. In the present study, the following research hypothesis was put forth: a hydromorphological characterization of habitats is a significant element explaining the nature of water mite communities, and the RHS method can be used to predict the characteristics of Hydrachnidia populations in a river. The research was carried out in a small lowland river, the River Krąpiel (north-western Poland). Six locations were selected as representative of some state of habitat modification for the assessment of the hydromorphological conditions of the river and the collection of biological samples. The following conclusions can be drawn from the research: (1) the biology and ecology of water mites make them suitable as bioindicators of the environment, including hydromorphological modifications, and (2) the hydromorphological characteristics of habitats explain the nature of water mite communities in the river at the level of general population parameters (number of specimens and species), while at the species level, general regularities in water mite fauna distribution in river ecosystems, the continuity of the river ecosystem, and characteristics at a smaller spatial scale (habitat scale) better explain water mite community structure than the hydromorphological indices determined for a given site or section of the river. [ABSTRACT FROM AUTHOR]

Environmental pollution and degradation caused by the processing and refining of crude oil has been on the increase since its discovery in the Niger Delta region of Nigeria. Its negative impacts are unquantifiable though its refined products are of immense benefits to the nation and the world at large. An assessment of the performance of Pistia stratiotes as affected by the water soluble fraction of Universal Energy Akwa Ibom crude oil was carried out in Abraka, Delta State, Nigeria in 2023. The five levels of WSF (0, 10, 25, 50, 75 and 100%) were used. Pistia stratiotes thalli were obtained from below the Bridge along River Ethiope and exposed to the different treatments. The results showed a significant reduction (p≤0.05) in all the plant parameters measured (leaf area, plant number, fresh weights, dry weight biomass, relative growth rate and survival percentage) in plants grown in the WSF media when compared to their counterparts exposed to the control plots. Against the normal healthy plants observed in the control, signs of dieback, yellowness of leaves, suppress growth and deaths were observed in plants subjected to the water soluble fraction of the crude oil and the effects were WSF dose dependent. There was gradual reduction in the shoot biomass of the plant with increasing level of WSF. There is a gradual increase in the root biomass although there was a total root growth. The study has established that the performance of Pistia stratiotes was significantly affected by the presence of water soluble fraction of crude oil. The study has great implication on water biology and food security. Continuous environmental monitoring and remediation exercises should be conducted in oil producing communities by the government. [ABSTRACT FROM AUTHOR]

Increasingly, scientists and non-scientists, especially employees of government agencies, tend to use weak or equivocal language when making statements related to science policy and governmental regulation. We use recent publications to provide examples of vague language versus examples of strong language when authors write about regulating anthropogenic pressures on natural resources. Lifeless language is common in agency reports, policy documents, and even scientific papers published by academics. Such language limits success in regulating anthropogenic pressures on natural resources. This challenge must be recognized and countered as a driver of the condition of water and associated resources. We also list sources of vague wording, provide global examples of how ambiguous language and political influences have contributed to water resource degradation, discuss the recent history of science censorship, and offer possible solutions for more direct scientific discourse. We found that: (1) equivocal language was especially common in concluding statements and not only by government employees; (2) authors discussed confusing language concerns in an agency publication; and (3) agency employees sometimes used active, strong language. Key drivers of weak language include: (1) holding on to old paradigms and resisting new knowledge; (2) scientific uncertainty; (3) institutional manuscript review policies; (4) employment and funding insecurity; and (5) avoiding the appearance of advocacy. Examples associated with euphemistic language included climate change, flow and physical habitat alteration, dams, agriculture, mining, forestry, and fisheries, as well as resistance towards monitoring, assessing, and reporting ecological conditions. Suggestions for mitigating equivocal language involve employment protections and greater focus on scientific ethics. We conclude that natural resource scientists should resist calls to employ imprecise language. Instead, they should be strong advocates for prescriptive and protective natural resource actions--based on their science--to halt and reverse the systemic degradation of those resources. [ABSTRACT FROM AUTHOR]

Summary: Coral conservation requires a mechanistic understanding of how environmental stresses disrupt biomineralization, but progress has been slow, primarily because corals are not easily amenable to laboratory research. Here, we highlight how the starlet sea anemone, Nematostella vectensis, can serve as a model to interrogate the cellular mechanisms of coral biomineralization. We have developed transgenic constructs using biomineralizing genes that can be injected into Nematostella zygotes and designed such that translated proteins may be purified for physicochemical characterization. Using fluorescent tags, we confirm the ectopic expression of the coral biomineralizing protein, SpCARP1, in Nematostella. We demonstrate via calcein staining that SpCARP1 concentrates calcium ions in Nematostella, likely initiating the formation of mineral precursors, consistent with its suspected role in corals. These results lay a fundamental groundwork for establishing Nematostella as an in vivo system to explore the evolutionary and cellular mechanisms of coral biomineralization, improve coral conservation efforts, and even develop novel biomaterials.

Factors influencing the distribution and variations of abundance of phytoplankton of dams are yet to be accounted for in Southwest Nigeria. Therefore, the objective of this paper was to evaluate the seasonal distribution and variations of abundance of phytoplankton community in Ikere Gorge Dam, Oyo State, Southwest Nigeria using standard techniques. Data obtained show that a total of 494 microalgal taxa belonging to eight divisions were recorded. Zygnematophyceae comprised 360 taxa (64%), Bacillarophyceae 22 taxa (14%), Chlorophyceae 66 taxa (13%), Cyanophyceae 20 taxa (4%), Dinophyceae 8 taxa (1%), Trebouxiophyceae 13 taxa (2%), Ulvophyceae 3 taxa (0.02%), Xanthophyceae 2 taxa (0.01%). The observations and results confirm hypotheses that phytoplankton abundance varies more between season (wet and dry) than spatially in Ikere gorge dam. No single taxon or a combination of two or three taxa accounted for more than 80% of the phytoplankton abundance. Canonical correspondence analysis revealed DO, TDS, nitrate-nitrogen and water transparency as the major water quality variables driving variation in the composition of plankton communities in the dam. This study showed seasonality is the major factor influencing the diversity and abundance of phytoplankton community through changes in concentrations of DO, nitrates, and phosphate. Ikere Gorge dam showed a strong seasonal variation in physico-chemical water quality variables owing to the size of the dam that is not well-mixed, and with long water residence times. This study contributes to understanding the water quality, determinant factors, and drivers of biological communities in dams of tropical regions that are being influenced by anthropogenic activities.

Summary: The intricate coexistence of Symbiodiniacean algae with a diverse range of marine invertebrates underpins the flourishing biodiversity observed within coral reef ecosystems. However, the breakdown of Symbiodiniaceae–host symbiosis endangers these ecosystems, necessitating urgent study of the symbiotic mechanisms. The symbiosis between nudibranchs and Symbiodiniaceae has been identified as an efficacious model for examining these mechanisms, yet a comprehensive understanding of their histological structures and cellular processes remains elusive. A meticulous histological exploration of the nudibranch Pteraeolidia semperi, employing optical, fluorescence, and electron microscopy, has revealed fine tubules extending to the body surface, with associated epithelial cells having been shown to adeptly encapsulate Symbiodiniaceae intracellularly. By tracing the stages of the “bleaching” in nudibranchs, it was inferred that algal cells, translocated via the digestive gland, are directly phagocytosed and expelled by these epithelial cells. Collectively, these insights contribute substantially to the scholarly discourse on critical marine symbiotic associations.

This paper introduces a real-time water quality dataset of five ponds for fish farming obtained through an IoT framework for monitoring the aquatic environmental conditions. It utilizes sensors and an Arduino microcontroller to collect data on pH, temperature, and turbidity in pond water in Jamalpur District, Bangladesh. The data is stored in an IoT cloud platform named ThingSpeak and analyzed using 10 machine learning algorithms. The dataset consists of 4 columns and 40,280 rows, where pH, temperature, turbidity, and fish are recorded. Fish represents the target variable, while the others serve as independent variables. Within the dataset, there are 11 distinct fish categories including sing, silver carp, Katla, prawn, karpio, shrimp, rui, pangas, tilapia, magur, and koi. Results showed that only three ponds are suitable for fish farming among five ponds and the Random Forest algorithm performs the best. The study also includes details of the IoT system's hardware. This dataset will be useful for researchers and fish farmers to predict fish survival.

The article deals with the relationship between morphometry and hydrobiological regime. The Shurtan reservoir located in the southern part of the Republic of Uzbekistan is chosen as the Object of the study. Studying the problem of reservoir overgrowth and its connection with morphometry, especially in reservoirs with depth up to 2 metres, and the influence of sunlight penetration, requires application of various research methods. The water level mark in the reservoir during the period of field studies was ∇ 420.325 m, the reservoir water volume was 7.5 million m3 and the water surface area was 7.10 km2. On the basis of application of modern technologies of geoinformation system for assessment of hydrological and hydrobiological processes on the reservoir, an electronic map of the Shurtan reservoir basin was made. The results of the study using GIS technologies showed that the coastal zones of the reservoir bowl are covered with algae (reeds), their area is growing every year. If its area in 2007 was-0.386km2, in 2014 it reached an area of 0.677km2. In 2018, work was done to clear the coastal zones of vegetation, but by 2023 everything is covered with plants again. [ABSTRACT FROM AUTHOR]

The River Indus is one of the most extended water bodies in Pakistan. It is a source of drinking water, hydroelectric power generation, irrigation, agriculture and aquaculture. The present examination wanted to survey the river's physicochemical parameters and biodiversity from June 2016 to May 2017. Total eight stations have been selected along the Indus River, and 08 water quality parameters, i.e., temperature, salinity, dissolved oxygen, power of hydrogen, transparency, alkalinity, hardness, and total dissolved solids, have been checked from all stations on the spot and bring water samples in a plastic bottle. Fish samples were also collected from all stations, preserved all the samples in 10% formalin, and further investigated in the Fresh Water Biology Laboratory at the University of Sindh Jamshoro. A total of 45 fish species have been identified throughout the study period. [ABSTRACT FROM AUTHOR]

Small dolphins in a small sea: Age, growth and life-history aspects of the black sea common bottlenose dolphin Tursiops truncatus. Age and growth patterns of individuals are indicators of population demography and life-history traits, providing evidence of the dynamics, health, and potential responses to environmental changes (Danil & Chivers, [15]; Hohn, [26]; Huang et al., [28]). We chose the Gompertz model for further sex comparisons of TL and MG (Figure 3). 1 TABLE Growth parameters related to total length (cm) and maximum girth (cm) for common bottlenose dolphins (Tursiops truncatus) from the central region of Sabana-Camagüey Archipelago, Cuba. Age distribution and growth of two bottlenose dolphin (Tursiops truncatus) populations from capture-release studies in the southeastern United States. [Extracted from the article]

In the present study, we report on the Eurasian Ruffe (Gymnocephalus cernuus) in the Mandra Lake at City of Burgas. This is the only water basin in southeastern Bulgaria that is known to be inhabited by the species. The Eurasian Ruffe was detected in Mandra Lake for the first time in 1998; since then, there has been no information concerning the local population. We captured two adult G. cernuus in the winter of 2020 and propose these specimens represent a permanent viable population. In this study, we report the first specimens registered by professional biologists, thus confirming the data acquired by sports fishermen over the years. [ABSTRACT FROM AUTHOR]

Summary: Marine group II (MGII) is the most abundant planktonic heterotrophic archaea in the ocean. The evolutionary history of MGII archaea is elusive. In this study, 13 new MGII metagenome-assembled genomes were recovered from surface to the hadal zone in Challenger Deep of the Mariana Trench; four of them from the deep ocean represent a novel group. The optimal growth temperature (OGT) of the common ancestor of MGII has been estimated to be at about 60°C and OGTs of MGIIc, MGIIb, and MGIIa at 47°C–50ºC, 37°C–44ºC, and 30°C–37ºC, respectively, suggesting the adaptation of these species to different temperatures during evolution. The estimated OGT range of MGIIc was supported by experimental measurements of cloned β-galactosidase that showed optimal enzyme activity around 50°C. These results indicate that MGIIc may have originated from a common ancestor that lived in warm or even hot marine environment, such as hydrothermal vents.

Summary: Antibiotic resistance genes (ARGs) are emerging as environmental pollutants that can persist and disseminate in aquatic environments. Lakes, as important sources of freshwater, also serve as potential natural reservoirs of ARGs. In this study, we analyzed the distribution and potential risks of resistance genes in five typical freshwater lakes on the Yunnan-Guizhou Plateau. Our findings revealed that multidrug and MLS ARGs dominated in the studied lakes. Notably, while Lugu Lake exhibited higher abundance of ARGs, mobile genetic elements (MGEs), and metal resistance genes (MRGs), a greater resistome risk was observed in the eutrophic Xingyun Lake. The dissemination processes of ARGs and MRGs are primarily driven by microbial communities and the horizontal gene transfer via MGEs. Limnohabitans, Flavobacterium, and Acinetobacter were identified as key players in the dissemination of ARGs. Our study highlights the persistence of ARGs and provides valuable baseline data and risk assessment of ARGs in plateau freshwater lakes.

Summary: Trade restrictions for endangered elasmobranch species exist to disincentivise their exploitation and curb their declines. However, trade monitoring is challenging due to product variety and the complexity of import/export routes. We investigate the use of a portable, universal, DNA-based tool which would greatly facilitate in-situ monitoring. We collected shark and ray samples across the Island of Java, Indonesia, and selected 28 commonly encountered species (including 22 CITES-listed species) to test a recently developed real-time PCR single-assay originally developed for screening bony fish. In the absence of a bespoke elasmobranch identification online platform in the original FASTFISH-ID model, we employed a deep learning algorithm to recognize species based on DNA melt-curve signatures. By combining visual and machine-learning assignment methods, we distinguished 25/28 species, 20 of which were CITES-listed. With further refinement, this method can improve monitoring of the elasmobranch trade worldwide, without a lab or species-specific assays.

Summary: Marine biofouling causes huge economic losses to the marine industry every year. Albofungin is a potential antifoulant showing strong anti-macrofouling activities against larval settlement of major fouling organisms. In the present study, directed RNA-seq and proteomic analyses were used to investigate changes in the transcriptome and proteome of a major fouling barnacle Amphibalanus amphitrite cyprids in response to albofungin treatment. Results showed that albofungin treatment remarkably upregulated the metabolism of xenobiotics by the cytochrome P450 pathway to discharge the compound and downregulated energy metabolic processes. Intriguingly, immunostaining and whole-mount in situ hybridization (WISH) revealed the spatial expression patterns of selected differentially expressed genes (glutathione S-transferase [GST], nitric oxide synthase [NOS], and calmodulin [CaM]) distributed in the thorax and antennule of A. amphitrite. Our study provides new insights into the mechanism of albofungin in interrupting the larval settlement of A. amphitrite and suggests its potential application as an antifouling agent in marine environments.

Summary: Mesophotic reefs have been proposed as climate change refugia but are not synonymous ecosystems with shallow reefs and remain exposed to anthropogenic impacts. Planulae from the reef-building coral Stylophora pistillata, Gulf of Aqaba, from 5- and 45-m depth were tested ex situ for capacity to settle, grow, and acclimate to reciprocal light conditions. Skeletons were scanned by phase contrast-enhanced micro-CT to study morphology. Deep planulae had reduced volume, smaller diameter on settlement, and greater algal symbiont density. Light conditions did not have significant impact on settlement or mortality rates. Photosynthetic acclimation of algal symbionts was evident within 21–35 days after settlement but growth rate and polyp development were slower for individuals translocated away from their parental origin compared to controls. Though our data reveal rapid symbiont acclimation, reduced growth rates and limited capacity for skeletal modification likely limit the potential for mesophotic larvae to settle on shallow reefs.

The presence of pharmaceuticals in the aquatic environment presents a challenge to modern science. The most significant impact this can induce is the emergence of antibiotic resistance, which can lead to a global health emergency. It is important to note that the impact of pharmaceuticals in the aquatic environment is not limited to antibiotic resistance. Pharmaceuticals can also affect the behaviour and reproductive systems of aquatic organisms, with cascading effects on entire ecosystems. Numerous studies have reported the emergence of pharmaceuticals due to the uncontrolled disposal of polluted domestic, agricultural, and industrial wastewater in water bodies. This work discusses the potential of pharmaceuticals that on one hand are highly important for mankind, yet their non-judicious usage and disposal induce equally intriguing and problematic conditions to the health of aquatic systems. Pathways through which pharmaceutics can make their way into water bodies are discussed. Furthermore, the risk imposed by pharmaceuticals on aquatic life is also elaborated. The possible and pragmatic remediation methods through which pharmaceutical products can be treated are also discussed. Emphasis is placed on the potential of phytoremediation and advanced oxidative process, and the factors affecting the efficacy of these remediation methods are discussed. [ABSTRACT FROM AUTHOR]

The data obtained by the authors confirm that I Unionicola i mites are narrow host specialists that are associated with either one or a few closely related freshwater mussel species belonging to one or two sister genera. They discovered 39 taxa that belonged to the genus I Mallomonas i (37 taxa) and the genus I Synura i (2 taxa). Some articles on the communities of aquatic ecosystems included a broad spectrum of taxonomic groups. Twenty-one studies on the diversity of aquatic organisms inhabiting water ecosystems in Europe, Asia, Africa, North America, and Oceania were collected for the current Special Issue. [Extracted from the article]

In 2018, the hardscape construction of NCOS (North Campus Open Space), a restored wetland on the Northern border of COPR (Coal Oil Point Reserve), was completed, thus approximately doubling the overall size of the wetland and offering the rather unique opportunity of being able to compare the two side-by-side.  Basic water quality and aquatic invertebrate monitoring of both sites were undertaken to better understand the dynamics of how a newly constructed wetland developed into an established wetland.The surprising result of this first year of monitoring is that COPR and NCOS were more or less equivalent in species richness and abundance, with the Shannon-Wiener Index giving a slight nod to NCOS for more diversity and Evenness in the data.Four taxa are the most significant contributors to the total taxa observed – Copepods, Ostracods, Cladocera, and Corixidae.  Additionally, we found Chironomids, Ceratopogonidae, Ephydridae, and Nematodes in significant abundance.Sampling protocols were evaluated indicating that sampling in algae gives more than an order-of-magnitude greater abundance and diversity than in sampling in open water and that the Filtered Beaker method gives more precise species density information than the Sweep-Net method; when sampling at shallower depths where the Sweep-Net is not fully submerged.Additionally, the effect on other aquatic invertebrates of the use of VectoBac for mosquito abatement was looked at – indicating a minimum, if any, affect.