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Long non-coding RNA (lncRNA) is a novel emerging type of competitive endogenous RNA (ceRNA) that performs key functions in multiple biological processes. However, little is known about the roles of lncRNA under hypoxia stress in fish. Here, vascular endothelial growth factor-Aa (vegfaa) was cloned in rainbow trout (Oncorhynchus mykiss), with the complete cDNA sequence of 2914 bp, encoding 218 amino acids. The molecular weight of the protein was approximately 25.33 kDa, and contained PDGF and VEGF_C domains. Time-course and spatial expression patterns revealed that LOC110520012 was a key regulator of rainbow trout in response to hypoxia stress, and LOC110520012, miR-206-y and vegfaa exhibited a ceRNA regulatory relationship in liver, gill, muscle and rainbow trout liver cells treated with acute hypoxia. Subsequently, the targeting relationship of LOC110520012 and vegfaa with miR-206-y was confirmed by dual-luciferase reporter analysis, and overexpression of LOC110520012 mediated the inhibition of miR-206-y expression in rainbow trout liver cells, while the opposite results were obtained after LOC110520012 silencing with siRNA. We also proved that vegfaa was a target of miR-206-y in vitro and in vivo , and the vegfaa expression and anti-proliferative effect on rainbow trout liver cells regulated by miR-206-y mimics could be reversed by LOC110520012. These results suggested that LOC110520012 can positively regulate vegfaa expression by sponging miR-206-y under hypoxia stress in rainbow trout, which facilitate in-depth understanding of the molecular mechanisms of fish adaptation and tolerance to hypoxia. • The full-length cDNA sequence of vegfaa was 2914 bp encoding 218 amino acids. • LOC110520012 and vegfaa were highly expressed under hypoxia stress. • vegfaa was shown to a direct target of miR-206-y in vitro and in vivo. • LOC110520012 acted as a ceRNA of vegfaa by sponging miR-206-y. • The inhibitory effect of miR-206-y on rainbow trout liver cell proliferation could be alleviated by LOC110520012. [ABSTRACT FROM AUTHOR]

Hypoxia, largely triggered by global warming and water contamination, has become an environmental issue of great concern, posing a great threat to aquatic ecosystem. As one of the world's most economically important fish, rainbow trout (Oncorhynchus mykiss) is extremely intolerant of hypoxic environments, however, little is known about the roles of non-coding RNAs (ncRNAs) in the response of rainbow trout to hypoxia stress. Herein, effects of moderate (Tm12L) and severe hypoxia for 12 h (Ts12L) and 12 h reoxygenation on histology, biochemical parameters (antioxidant, metabolism and immunity) and transcriptome (lncRNA, miRNA and mRNA) in rainbow trout liver were investigated. We further validated the regulatory relationships between LOC110519952, novel-m0023-5p and glut1a via dual‑luciferase reporter, overexpression and silencing assays. Compared with Tm12L, the liver in Ts12L showed more severe oxidative damage. Anaerobic, lipid and protein metabolism was enhanced under hypoxia stress, especially in Ts12L. We also found that Tm12L could strengthen innate immune response, which was inhibited in Ts12L. Besides, several hypoxia-related genes (glut1a , vegfaa , hmox , epoa , foxo1a and igfbp1) and ceRNA networks were identified from 1824, 427 and 545 differentially expressed mRNAs, miRNAs and lncRNAs, including LOC118965299-novel-m0179-3p- epoa , LOC110519952-novel-m0023-5p- glut1a , MSTRG.7382.2-miR-184-y- hmox and LOC110520012-miR-206-y- vegfaa. Through in vitro and in vivo functional analysis, we demonstrated that glut1a is a target of novel-m0023-5p, and LOC110519952 can positively regulate glut1a by targeting novel-m0023-5p. Introduction of LOC110519952 could attenuate the promoting effects of novel-m0023-5p on rainbow trout liver cell viability and proliferation. This study highlights the differences in the regulatory mechanism of rainbow trout under different concentrations of hypoxia stress and provides valuable data for further research on the molecular mechanisms of fish adaptation to hypoxic environments. [Display omitted] • Anaerobic metabolism was strongly enhanced under severe hypoxia. • Innate immune response was inhibited under severe hypoxia. • Numerous hypoxia-related genes and lncRNA-miRNA-mRNA networks were identified. • LOC110519952 functioned as ceRNA to target glut1a by sponging novel-m0023-5p. • Overexpressed novel-m0023-5p promoted cell viability and proliferation. [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia 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.)

An undescribed species of Microcambeva , a genus of small psammophilic catfishes from the Atlantic Forest of south-eastern Brazil, was found together the congener Microcambeva ribeirae inhabiting the same sand stretch of a stream, in the Rio Ribeira do Iguape basin. The new species and its sympatric congener exhibit highly divergent morphological features, but a multigene phylogeny support them as sister taxa. The new species, M. filamentosa sp. nov., is readily distinguished from all other congeners by the presence of long barbels, long filamentous first pectoral-fin ray and a hypertrophied predorsal adipose fold. Microcambeva filamentosa and M. ribeirae share two unique apomorphic features: a single supraorbital pore s6 situated on the centre of the dorsal surface of the head and a deep concavity between the dorsal process of the opercle and the opercular odontode patch, conditions that are independently acquired in other psammophilic trichomycterids. A comparative context, involving other trichomycterid lineages exhibiting similar morphological adaptations, highly suggests that morphological differences between M. filamentosa and M. ribeirae are related to different strategies to exploit their habitat. In M. ribeirae , the short and thickened first pectoral-fin ray is interpreted as an adaptation to the fish posing propped on the substratum while visually detecting potential preys, what is reinforced by the unique possession in this taxon of a relatively large eye positioned on the top of the head. On the other hand, the relatively small eye and long barbels of M. filamentosa highly suggest the use of a predominantly chemosensory and tactile detection of food, indicating possible nocturnal habits. [ABSTRACT FROM AUTHOR]

Temperature is a critical factor that regulates the reproduction processes in teleost. However, the gonadal response mechanism to cold stress in fish remains largely unknown. In the present study, female zebrafish were exposed to different extents of low temperatures at 18 °C and 10 °C for 48 h. The ovarian histology was remarkably damaged after cold stress exposure. Integrated analysis of miRNA-mRNA was used to investigate the ovarian response to acute cold stress. A large number of mRNAs and miRNAs were altered by cold stress, which are involved in extensive biological processes. It is indicated that the signal transduction of MAPK and Calcium signaling pathway is highly engaged in zebrafish ovary to adapt to cold stress. The immune system was dysregulated by cold stress while the ovarian autophagy was activated. Remarkably increased gene number related to reproductive functions was identified in the cold stress at 10 °C compared to the control. The cold stress-induced dysregulated reproductive genes include star , hsd3b1 , hsd17b1 , inha , insl3 , amh , nanos1 and foxl2. Combined with the dysregulated insulin, IGF and progesterone signaling, it is suggested that cold stress affects ovarian function in multiple aspects, including oocyte meiosis, folliculogenesis, final maturation and ovarian maintenance. On the other hand, the ovarian miRNA-mRNA regulatory network response to cold stress was also constructed. Overall, our result revealed the ovarian response to cold stress in zebrafish and provided insight into the fish adaptation mechanism to acute temperature change. [Display omitted] • Ovarian response to cold stress was investigated by miRNA-mRNA analysis. • Cold stress altered ovarian signal transduction, immune system, and autophagy. • Oocyte maturation was inhibited by defects on insulin and progesterone signaling. • Cold stress dysregulate ovarian function from multiple aspects. [ABSTRACT FROM AUTHOR]

Climate change has had profound effects on coastal ecosystems, including sea level rise, ocean acidification, and extreme weather events. These impacts have left vulnerable populations in coastal areas, particularly fishing communities, struggling to maintain their livelihoods, subsistence, and cultural practices that rely on a healthy ecosystem. The existing body of research has examined the impacts of climate change on fishing communities and their perceptions and responses to environmental issues. However, these studies have employed diverse conceptual and methodological approaches. Therefore, our study aimed to identify the key concepts, frameworks, challenges, and trends evident in these previous studies. To achieve this objective, we conducted a comprehensive literature review of 34 papers and employed both quantitative and qualitative analyses to evaluate them. Our analysis revealed several primary challenges encountered in these studies, including insufficient data availability, variations in data quality, difficulties in effective communication with local communities, and inadequate inclusion of women's knowledge and perspectives. By recognizing these challenges, we can highlight areas for improvement and further research. The findings of our study indicate that the most prevalent frameworks utilized in the selected studies can be classified into three groups: "Local knowledge," which focused on understanding the perceptions of climate change impacts among small-scale fishers; "Vulnerability," which aimed to comprehend the components and measurements of vulnerability in fishing communities; and "Adaptation and Resilience," which explored how these communities respond to climatic events. Furthermore, our study identified emerging trends in the development of research on local knowledge, gender roles, and adaptive capacity within fishing communities. In conclusion, this study serves as a general guide and starting point for refining and enhancing frameworks used to investigate the effects of climate change on small-scale fisheries. • Small-scale artisanal fisheries face complex challenges, such as overfishing, habitat degradation, and climate change impacts. • Conceptual frameworks (CFs) are used to comprehend the interactions between climate change impacts and fishing communities. • Three major groups of CFs have emerged from the study, named as local knowledge, vulnerability, and resilience frameworks. • Adaptive capacity is a fundamental concept within both the vulnerability and resilience frameworks. • Data availability, quality issues, and underrepresentation of women are identified as barriers and challenges. [ABSTRACT FROM AUTHOR]

Mandarin fish (Siniperca chuatsi) is a carnivorous freshwater fish and an economically important species. The digestive system (liver, stomach, intestine, pyloric caecum, esophagus, and gallbladder) is an important site for studying fish domestication. In our previous study, we found that mandarin fish undergoes adaptive changes in histological morphology and gene expression levels of the digestive system when subjected to artificial diet domestication. However, we are not clear which hub genes are highly associated with domestication. In this study, we performed WGCNA on the transcriptomes of 17 tissues and 9 developmental stages and combined differentially expressed genes analysis in the digestive system to identify the hub genes that may play important functions in the adaptation of mandarin fish to bait conversion. A total of 31,657 genes in 26 samples were classified into 23 color modules via WGCNA. The modules midnightblue, darkred, lightyellow, and darkgreen highly associated with the liver, stomach, esophagus, and gallbladder were extracted, respectively. Tan module was highly related to both intestine and pyloric caecum. The hub genes in liver were cp , vtgc , c1in , c9 , lect2 , and klkb1. The hub genes in stomach were ghrl , atp4a , gjb3 , muc5ac , duox2 , and chia2. The hub genes in esophagus were mybpc1 , myl2 , and tpm3. The hub genes in gallbladder were dyst , npy2r , slc13a1 , and slc39a4. The hub genes in the intestine and pyloric caecum were slc15a1 , cdhr5 , btn3a1 , anpep , slc34a2 , cdhr2 , and ace2. Through pathway analysis, modules highly related to the digestive system were mainly enriched in digestion and absorption, metabolism, and immune-related pathways. After domestication, the hub genes vtgc and lect2 were significantly upregulated in the liver. Chia2 was significantly downregulated in the stomach. Slc15a1 , anpep , and slc34a2 were significantly upregulated in the intestine. This study identified the hub genes that may play an important role in the adaptation of the digestive system to artificial diet, which provided novel evidence and ideas for further research on the domestication of mandarin fish from molecular level. [Display omitted] • The special modules and hub genes highly associated with digestive system of mandarin fish in each tissue including the liver, stomach, intestine, pyloric caecum, esophagus, and gallbladder were identified based on WGCNA • Genes within the modules were mainly enriched in the digestion and absorption, metabolic, and immune-related pathways. • Vtgc , lect2 , chia2 , slc15a1 , anpep , and slc34a2 genes may play an important role in the adaptation of the digestive system to artificial diet. [ABSTRACT FROM AUTHOR]

By considering the economic and social contribution of Senegalese artisanal fisheries to the national economy, this study firstly provides elements of analysis of the disruptions caused by the coronavirus pandemic in the fishing sector. Secondly, it lifts the veil on the adaptation strategies of the actors concerned. The field surveys reveal that the response measures of the authorities have affected the production, distribution, and marketing chains of fisheries products. The results show a remarkable decrease in landings. The landings of pelagic fish species in Ouakam, Hann, Soumbédioune, and Mbour fishing ports have decreased by −10.11%, −61.25%, −9.75%, and −18.98% proportionately. The same downward trend for demersal fish species was observed, except in Ouakam fishing port. The landing increased slightly to 29.28%. Also, significant income losses have been reported, particularly by fish traders, following the closure of the air borders and the decrease in the selling prices of species formerly destined for export. Thus, faced with this problem, the artisanal fishermen have developed site-specific strategies to continue their activities, which have slowed down. However, this pandemic has paralyzed artisanal fisheries activities, demonstrating the need for this study to strengthen the economic resilience of the sector. • Coronavirus pandemic disturbed the Senegalese artisanal fishing sector. • The actor developed some strategies to thwart the harmful effects of coronavirus. • The decrease in catches has led to a drop in the revenues of the actors. • Prices for some export species changed before and during the pandemic. [ABSTRACT FROM AUTHOR]

Hypoxia in water environment has become increasingly frequent and serious due to global warming and environmental pollution. Revealing the molecular mechanism of fish hypoxia adaptation will help to develop markers of environmental pollution caused by hypoxia. Here, we used a multi-omics method to identify the hypoxia-associated mRNA, miRNA, protein, and metabolite involved in various biological processes in Pelteobagrus vachelli brain. The results showed that hypoxia stress caused brain dysfunction by inhibiting energy metabolism. Specifically, the biological processes involved in energy synthesis and energy consumption are inhibited in P. vachelli brain under hypoxia, such as oxidative phosphorylation, carbohydrate metabolism and protein metabolism. Brain dysfunction is mainly manifested as blood-brain barrier injury accompanied by neurodegenerative diseases and autoimmune diseases. In addition, compared with previous studies, we found that P. vachelli has tissue specificity in response to hypoxia stress and the muscle suffers more damage than the brain. This is the first report to the integrated analysis of the transcriptome, miRNAome, proteome, and metabolome in fish brain. Our findings could provide insights into the molecular mechanisms of hypoxia, and the approach could also be applied to other fish species. The raw data of transcriptome has been uploaded to NCBI database (ID: SUB7714154 and SUB7765255). The raw data of proteome has been uploaded to ProteomeXchange database (PXD020425). The raw data of metabolome has been uploaded to Metabolight (ID: MTBLS1888). • First multi-omics analysis of mRNA, miRNA, protein and metabolite in fish brain. • The P. vachelli has tissue specific response to hypoxia stress. • The energy metabolism in P. vachelli brain was inhibited under hypoxia stress. [ABSTRACT FROM AUTHOR]

Background. In this study, the relation between the biological reference points (BRPs) associated with Maximum Sustainable Yield (MSY) and the relevant biological, fisheries, and environmental factors were investigated. This knowledge is crucial to build the capacity for timely adaptation of management to the changes in an ecosystem. The research highlights the considerations that need to be taken into account when estimating and using BRPs in practice, and can thus lead to avoidance of overfishing. The BRPs were represented by MSY and the related spawning stock biomass (BMSY), fishing mortality (FMSY), and FMSY proxies. Materials and methods. To obtain the BRPs, the method of Horbowy and Luzeńczyk (2012)--that combines yield-per-recruit and spawning stock-per-recruit analyses with stock-recruitment relation models (Beverton and Holt (B&H) 1957, Ricker 1975)--was used. Data from the three biggest Baltic Sea stocks were used to test the sensitivity of BRPs to the model input data, and the influence of regime shifts or dynamics of the biological and fisheries variables on the BRPs. Results. The analyses show that an increase in maturity and weight at age generally led to an increase in BRPs. The opposite effect is observed in the case of natural mortality (stronger when the Ricker stock-recruitment (S-R) relation was used) and selectivity (proportion of the F of partially recruited age groups to the mean F of fully recruited age groups). An increase in the steepness of S-R models increases FMSY and its proxies as well as MSY, and had a decreasing influence on BMSY. Furthermore, the BRPs are very sensitive to the different data range divisions of the input data. Conclusion. When estimating BRPs, the time period of the input data should be selected with caution, and the appropriate time period should be based on strong biological, ecological, and environmental knowledge as, according to this study, all of these factors influence estimates of BRPs. [ABSTRACT FROM AUTHOR]

As the impacts of ocean and climate change become more pronounced, fishing communities are experiencing unprecedented disruptions to social and economic life. We argue that a broader interpretation of adaptation is required for a comprehensive understanding of fishers' adaptive responses. Instead of examining adaptation in relation to climate driven ocean changes alone, we argue that adaptive responses are shaped by and contingent on compounding social, economic, and environmental stressors. Although research has produced management frameworks to support adaptation, few concrete examples of management actions exist, particularly actions aimed at mitigating the impacts of compounding social and economic stressors. We share the results from a multi-sited case study in which we conducted a rapid ethnographic assessment of fishing communities on the US West Coast. By examining ocean change in the context of compounding stressors, our study brings two important points to light. First, fishers are employing a wider range of adaptation strategies than previously thought. Second, there are several unrealized institutional pathways that could support and remove barriers to adaption. Our analysis highlights how ocean change compounds existing stressors through two examples, labor shortages and finding new markets. Through this paper we argue that to support fishing community adaptation to climate change, agencies should explore a range of outside of the box solutions that address cumulative stressors. [ABSTRACT FROM AUTHOR]

Fish can adapt to a wide range of temperature changes, however, the molecular mechanisms that underlie these adaptations are not fully understood. In this study, fluorescently labeled differential display (FDD) technique was used to detect mRNAs that are differentially expressed in hepatic tissues of Tilapia zillii fish subjected to a temperature reduction regime that combined both accelerated and stationary cold stresses. The two arbitrary primers (DD1 and DD2) with the Oligo d(T) 23 -C generated a total of 18 and 37 unknown messenger RNA (UMR) bands, respectively. Both DD1 & DD2 arbitrary primers with oligo d(T) 23 -C scored four stress-related unidentified fragments after refining. Using the two arbitrary primers with the Oligo d(T) 23 -G, a total of 371 and 372 UmRs were yielded, respectively. Both arbitrary primers scored nine stress-related unidentified fragments after refining. All UmR were tested for its correlation to time and temperature factors scaled for the current experiment, only four were found to be correlated for both factors. Thus, T. zillii responded to temperature reduction by adjusting the expression of a set number of genes that may be required for their adaptation and tolerance to low environmental temperature. [ABSTRACT FROM AUTHOR]

Quantifying the effectiveness of management actions to mitigate the effects of changing climatic conditions (i.e., climate adaptation) can be difficult, yet critical for conservation. We used population genetic data from 1984 to 2011 to assess the degree to which ambient climatic conditions and targeted suppression of sources of nonnative Rainbow TroutOncorhynchus mykisshave influenced the spread of introgressive hybridization in native populations of Westslope Cutthroat TroutO. clarkii lewisi. We found rapid expansion in the spatial distribution and proportion of nonnative genetic admixture in hybridized populations from 1984 to 2004, but minimal change since 2004. The spread of hybridization was negatively correlated with the number of streamflow events in May that exceeded the 75th percentile of historic flows (r= −0.98) and positively correlated with August stream temperatures (r= 0.89). Concomitantly, suppression data showed a 60% decline in catch per unit effort for fish with a high proportion of Rainbow Trout admixture, rendering some uncertainty as to the relative strength of factors controlling the spread of hybridization. Our results illustrate the importance of initiating management actions to mitigate the potential effects of climate change, even where data describing the effectiveness of such actions are initially limited but the risks are severe. Received November 22, 2013; accepted March 1, 2014 [ABSTRACT FROM AUTHOR]

The article discusses a study which examined the link between the morphometric measurements of the catfish Lophiosilurus alexandri larvae and the importance of studying its allometric growth structures. It describes how the study was performed and the collection of morphometric data which include total length, eye diameter and body height. It also emphasizes the ability of L. alexandri larvae to adapt to its environment.

To reduce staffing demands and enhance observational accuracy, we designed, implemented, and tested a computerized system for processing underwater video clips captured by static cameras and removing “quiet” frames in which no activity is detected. When the system detects activity, it tracks and counts the moving object. The implementation uses an adaptive background-subtraction algorithm for detection and motion prediction for tracking. The system can be used to reduce the amount of video that must be reviewed by personnel, and it can produce total fish passage counts through the monitored area. The automated system reduced the total number of video hours requiring review by an average of 87.5% for count window videos and 83.5% for videos of picketed leads and lamprey passage orifices. The software detected 98.6% of the 144 Pacific LampreysEntosphenus tridentatusthat were observed in 185 h of raw video. Because the system is fully automated, monitoring requirements are negligible, and the cost reduction for fish monitoring is proportional to the number of quiet frames removed. Received March 27, 2013; accepted September 23, 2013 [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia 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 Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia 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.)

• Fish genomes are under a strong influence of climate, habitat, and depth. • GS decreased with latitude, salinity, and depth, the GC contents increased. • Higher GC contents were found to be mostly associated with species occupying physiologically challenging or stressful environmental niches. • Opposing trends in GS and GC to be the hallmark of environmental adaptation in fishes. Environmental interactions and the effects of such interactions on the evolution of genome attributes is an intriguing area of ongoing research. Several earlier studies have delved into how the genome size (GS) and the guanine-cytosine content (GC) of genomes are shaped by species' ecology while largely disregarding other genome attributes, such as number of chromosomes (CR), number of genes (GE), and protein count (PC) from such comparisons. The present study was designed at understanding the influence of ecology––climate, habitat, and depth––on genome attributes by using the most current data on 579 whole fish genomes available at NCBI. Given the diverse and intricate roles of GS and GC in species adaptations to temperature, salinity, and hydrostatic pressure, the focus was on finding if and how the genomes responded to these stressors and if any common patterns existed in the genome-level responses. Our analyses exhibited some significant and intriguing trends for fishes as a whole while indicating strong effects of ecology on GS, GC, CR, and PC. Also, some very unique trends were observed on regressing GS and GC values across temperature, salinity, and depth clines. Accordingly, a very strong decline in the GS and a concomitant increase in GC were observed in species through the tropics/sub tropics to the temperate/poles, from freshwater to the marine habitats, and from the pelagic to bathydemersal depths. Observed patterns strongly support the notion that smaller GS and larger GC are associated with species inhabiting more stable environments and vice versa. The results also signify the effect of these patterns on protein flexibility and its role in tolerating stressful conditions. Observed patterns are discussed in the light of latitudinal biodiversity gradient, habitat complexity, and energy and metabolic expenditure hypothesis. [ABSTRACT FROM AUTHOR]

Abstract: Fishers'' responses to changes in resource access through the imposition of marine protected areas can be a critical factor influencing the likelihood of achieving management objectives. Face-to-face interviews with 114 commercial and charter fishers were conducted to investigate their responses and adaptation strategies to the increase in the size and number of no-take zones imposed by the 2004 Great Barrier Reef Marine Park zoning plan. Despite holding positive attitudes towards marine biodiversity protection, fishers were generally unsupportive of the new zoning plan 5 years after its implementation. Fishers'' lack of support was related to the perception that they had not been adequately engaged in the rezoning process and the perception of significant impacts of the zoning plan on fishing businesses. Fishers generally believed that the new zoning plan had a negative impact on their access to productive fishing areas, the numbers of fish they catch, the profitability of their fishing business, and their personal income. In response to the new no-take zones, fishers tended to redistribute their fishing activity to locations closer to their home port, and to locations already known to them through their previous fishing, resulting in an increase in high density fishing locations within the park. Despite the impacts that fishers experienced, most reported that they have adapted their fishing activity and fishing business at least moderately well to the new zoning plan, suggesting that many of the impacts experienced by fishers might be short-term and may decline over time as fishers learn to adapt to the new zoning system. The information provided should prove valuable as a baseline for continued monitoring of the costs and benefits of the Great Barrier Reef Marine Park rezoning into the future. [Copyright &y& Elsevier]

In a study using 14 paired-release groups over 10 release years, we compared the performance of hatchery summer steelhead that were acclimated as smolts (AC) for 16-57 d before release into ponds supplied with ambient stream water with that of fish trucked from the hatchery and directly released (DR) into Spring, Deer, and Little Sheep creeks in northeastern Oregon. After releasing the fish into streams, we monitored out-migration travel times and survival to Lower Granite Dam (LGD) on the Snake River using freeze brand marks or implanted passive integrated transponder tags in a subsample of each release group. Across all release groups, travel time was significantly slower for AC fish (34.7 d) than for DR fish (31.8 d), though there was no significant difference in survival probability to LGD. We used recoveries of coded wire tags to estimate smolt-to-adult survival (SAS) and a stray rate index (SRI) for the AC and DR strategies. Across all release groups, SAS was 33% higher and SRI 42% lower for AC steelhead. At each release site acclimation increased average SAS by at least 11% and decreased SRI by at least 16.5%. We found a significant, negative linear relationship between travel time to LGD and SAS; however, there was no significant relationship between survival to LGD and SAS, which implies that judgments about the success or failure of a novel rearing or release strategy should not be made based on out-migration survival. Acclimating juvenile steelhead produced significantly higher SAS and lower SRI in the hatchery program we evaluated; however, our results are not consistent with those of other steelhead acclimation studies. [ABSTRACT FROM AUTHOR]

Abstract: Marine organisms, living in the cold waters of the Southern Ocean, are exposed to high oxygen concentrations. Cold-adapted organisms have developed networks of defence mechanisms to protect themselves against oxidative stress. The dominant suborder Notothenioidei of the Southern Ocean is one of the most interesting models, within vertebrates, to study the evolutionary biological responses to extreme environment. Within bacteria, the psychrophilic Antarctic bacterium Pseudoalteromonas haloplanktis TAC125 gives the opportunity to explore the cellular strategies adopted in vivo by cold-adapted microorganisms to cope with cold and high oxygen concentration. Understanding the molecular mechanisms underlying how a range of Antarctic organisms have responded to climate change in the past will enable predictions as to how they and other species will adapt to global climate change, in terms of physiological function, distribution patterns and ecosystem balance. [Copyright &y& Elsevier]

The article presents a study on quantification of the home ranges and movement patterns of Caranx crysos, a pelagic carangid fish, in a petroleum platform complex. It states that the positions of 23 C. crysos, which were implanted with acoustic transmitters through surgery, were localized in the petroleum platform in the Gulf of Mexico with the use of a hydrophone network. It adds that the fish were tracked for 23 days in August 2005 and the home ranges of each fish were calculated throughout the study period. After tracking them, it shows that most fish prefer a discrete area in the platform complex. It also notes that more transmissions were detected during the day. The results show that the schooling of the pelagic species determines a home range within the structure's vicinity.

The article offers information on a study on coral reef fish recruitment in relation to marine fish populations. It discusses the factors affecting the return of larvae to coral reefs as well as the process of settlement of the fish. The author analyzes the ability of environmental factors in order to explain the temporal patterns of recruitment in coral reef fishes and distinguish the variables that are associated between settlement and pelagic larval stage. It presents the data collected with regards to fish settlement variables and larval environment variables. Information on the results of the conducted study relative to the effects of planktonic factors and environment in the recruitment of coral reef fishes is discussed.

A population of the non-migratory estuarine fish Fundulus heteroclitus (Atlantic killifish) resident to New Bedford (NB), Massachusetts, USA, an urban harbor highly contaminated with polychlorinated biphenyls (PCBs), demonstrates recently evolved tolerance to some aspects of PCB toxicity. PCB toxicology, ecological theory, and some precedence supported expectations of increased susceptibility to pathogens in NB killifish. However, laboratory bacterial challenges of the marine pathogen Vibrio harveyi to wild fish throughout the reproductive season and to their mature laboratory-raised progeny demonstrated comparable survival by NB and reference killifish, and improved survival by NB males. These results are inconsistent with hypothesized trade-offs of adaptation, and suggest that evolved tolerance in NB killifish may include mechanisms that minimize the immunosuppressive effects of PCBs. Compensatory strategies of populations persisting in highly contaminated environments provide a unique perspective for understanding the long-term ecological effects of toxic chemicals. [Copyright &y& Elsevier]

Summary: Much has been written in recent years regarding the advantages of marine protected areas (MPAs) as conservation tools. The benefits to fisheries have commonly been cited as primary motives in favour of the establishment of MPAs. To date, a good deal has been theorised with regard to the benefit of MPAs to fisheries in their adjacent areas, but there has been little empirical evidence to support or refute hypothetical claims. Considerations for fisheries’ benefits are different to those of ecological benefits in several respects. Economically, fishers’ livelihoods often depend on the marine reserve being successful. It is not enough to establish that populations of fish are growing due to protection; stocks, as well as individual fish have to be sufficiently large to be catchable by the industry. Furthermore, restrictions in fishable area ought to be compensated for by increases in catches over time. In terms of the biology of the fish themselves, evidence has shown that heavily exploited commercial fish stocks can take much longer to recover from over-exploitation than previously expected. Although there have been several studies that consider the effects of export and spill-over, there have been few that focus on the patterns that these phenomena might have on the surrounding fisheries; many assume that ecological patterns will manifest in the fishery with time. Recently, assessment methods and predictive models have been suggested for fisheries (e.g. Rapfish, Ecopath/Ecosim), some of which have been adapted specifically for MPAs. In this paper we review recent progress in the field of MPA research with particular focus on fisheries assessment. We also identify priorities, and knowledge gaps, for determining and accurately predicting the benefits of MPAs to fishers. [Copyright &y& Elsevier]

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia 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.)

A structure and adaptive features of epidermis of various fishes are analyzed in the paper. We consider the ways of excretion of mucus onto the body's surface, the action of it on the flow regime and the influence of both a body's shape and a speed of swimming on the topography of the secretory system. The mucus-producing function of the epidermis is shown to be determined by both the ecology surrounding a fish and the speed of swimming rather than by the stage of development of the scales. [ABSTRACT FROM AUTHOR]

The article reports on the result of a research study led by fisheries scientist Leonardo Guida of Monash University in Melbourne, Australia, which examined the effects of trawling on southern fiddler rays, Trigonorrhina dumerilii. The methodologies adopted include exposure to a catch-and-release simulation, replication of a trawling catch, and exposure to stress on-deck. A comparison between pregnant and non-pregnant ray mothers is described.