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Two research trips took us to the Kola Peninsula in northern European Russia, where we visited the Terskii Coast of the White Sea. There, we observed the development of nature tourism in this previously undervalued Subarctic destination. A network of local roads and trails has shaped the tourist development process. They not only serve as a key part of its mobility infrastructure, but also as a core element of local heritage that links otherwise scattered and isolated tourist sites. These sites vary from prehistoric petroglyphs and ancient cemeteries to salmon fishing camps and long stretches of natural shoreline. By exploring the long-term development and conceptualisation of the coastal road, we demonstrate the cultural and historical background and significance of these landscapes. Thus, we highlight the central position of roads and trails in the interactions of various groups of actors involved in tourism. [ABSTRACT FROM AUTHOR]

The consumption of raw or smoked fish entails significant microbiological risks, including contamination by pathogens such as Listeria monocytogenes, which can cause severe foodborne illnesses. This study explores the preservative use of piscicolin CM22, a novel bacteriocin derived from the psychrotolerant strain Carnobacterium maltaromaticum CM22, in two types of edible coatings (EC): chitosan-based and fish gelatin-based. An initial in vitro characterization of the technological and antimicrobial properties of these ECs with and without bacteriocin was conducted. The efficacy of the edible coatings was subsequently evaluated through shelf life and challenge tests against L. monocytogenes in raw and smoked fish products. The results demonstrated significant antimicrobial activity, with the chitosan-based coating containing piscicolin CM22 being the most effective in reducing microbial counts and maintaining pH and color stability. Furthermore, in the challenge test studies, both ECs effectively controlled L. monocytogenes, showing significant reductions in bacterial counts compared to the controls in fresh tuna, salmon, and smoked salmon. The ECs containing piscicolin CM22 reduced Listeria counts by up to 4 log CFU/g in raw and smoked fish samples, with effective control in smoked salmon for up to 15 days at refrigeration temperature. While further research is required to fully assess their preservation potential, these findings strongly indicate that piscicolin CM22-functionalized edible coatings hold significant potential for improving the quality and safety of fish products. [ABSTRACT FROM AUTHOR]

In marine species with large populations and high dispersal potential, large-scale genetic differences and clinal trends in allele frequency can provide insight into the evolutionary processes that shape diversity. Lumpfish, Cyclopterus lumpus , is found throughout the North Atlantic and has traditionally been harvested for roe and more recently used as a cleaner fish in salmon aquaculture. We used a 70 K SNP array to evaluate trans-Atlantic differentiation, genetic structuring, and clinal variation across the North Atlantic. Basin-scale structuring between the Northeast and Northwest Atlantic was significant, with enrichment for loci associated with developmental/mitochondrial function. We identified a putative structural variant on chromosome 2, likely contributing to differentiation between Northeast and Northwest Atlantic Lumpfish, and consistent with post-glacial trans-Atlantic secondary contact. Redundancy analysis identified climate associations both in the Northeast (N  = 1269 loci) and Northwest (N  = 1637 loci), with 103 shared loci between them. Clinal patterns in allele frequencies were observed in some loci (15%—Northwest and 5%—Northeast) of which 708 loci were shared and involved with growth, developmental processes, and locomotion. The combined evidence of trans-Atlantic differentiation, environmental associations, and clinal loci, suggests that both regional and large-scale potentially-adaptive population structuring is present across the North Atlantic. [ABSTRACT FROM AUTHOR]

Objective: Although the bycatch of Pacific salmon Oncorhynchus spp. is relatively low in the Walleye Pollock Gadus chalcogrammus and Pacific Hake Merluccius productus pelagic trawl fisheries, different efforts are employed to reduce it, including the use of bycatch reduction devices (BRDs) that retain the targeted species and provide Pacific salmon a pathway to escape. The objective of this study was to evaluate Pacific salmon behavior inside a pelagic trawl and to determine what conditions favor the probability of a salmon moving forward in the trawl and increase their probability of escapement. Methods: We placed a video camera at the entrance of the cod end and recorded the behaviors of Pacific salmon as they passed by. The timing of the forward movement Pacific salmon in relation to fishing operations and the correlations between forward movement of Pacific salmon and vessel speed over ground, water flow rate, ambient light levels, and abundance of Walleye Pollock were examined. Result: Of the 2969 Pacific salmon observed, 71% were moving aft toward the cod end, 24% were observed moving forward, and 5% were moving aft then forward or forward then aft. The percentage (77%) and rate (0.86 fish per minute) of forward‐moving Pacific salmon was greatest once the trawl doors were back on the vessel and water flow within the trawl was reduced. Speed over ground and Walleye Pollock abundance were negatively correlated with forward movement of Pacific salmon. Only 6.5% of Pacific salmon that were in the cod end when fishing ended were able to move forward before the cod end was on the vessel. Conclusion: Pacific salmon can move forward in the trawl throughout fishing operations and haulback, but the percentage increases as the speed over ground and water flow inside the trawl is reduced. The low percentage of Pacific salmon that move forward after fishing has ended suggests that Pacific salmon escapement at the end of a tow is relatively low and suggests that BRD design should focus on stimulating escapement at the first BRD encounter. Impact statementA better understanding of Pacific salmon behavior inside of a pelagic trawl can be used to improve the design and use of devices that allow salmon to escape while retaining species that are targeted. Here we placed a camera near the end of a trawl to examine how Pacific salmon behave under varying fishing and environmental conditions. [ABSTRACT FROM AUTHOR]

Simple Summary: Phyto-based foods are becoming more and more popular worldwide, and people are consuming phyto-active components for purposes other than traditional health and nutrition. The study aimed to ascertain the impact of tea polyphenols (TPs) on fish. The outcomes showed that cold-water coho salmon exhibit improved growth, feed intake, and immunity. These results are helpful in promoting the development of novel feed additives for the aquaculture industry. To evaluate the impact of nutritional tea polyphenols (TPs) on body composition, growth, biochemical markers, antioxidant capacity, and hemato-immunological levels, a ten-week feeding experiment was carried out on coho salmon (Oncorhynchus kisutch, 180.51 ± 0.15 g). The control group was fed a basal diet; the T1, T2, T3, and T4 groups were fed 0.005%, 0.01%, 0.02%, and 0.04% TPs, respectively. These results demonstrate that adding TPs significantly (p < 0.05) increased the coho salmon fish's weight gain (WG), relative growth rate (RGR), condition factor (CF), feed efficacy (FE), daily growth rate (DGR), and specific growth rate (SGR). There was no discernible difference in the body compositions of the treated TPs and the control group (p > 0.05). In addition, the T3 group showed a significant (p < 0.05) decrease in GPT, LDL, HDL, TC, and CAT. Fish given a 0.02% diet containing TPs had significantly lower levels of malondialdehyde (MDA) in their liver; yet, the TP-treated groups had higher levels of SOD and CAT than the control (p < 0.05). The data analysis shows a significant rise in lysozyme, respiratory burst activity, bactericidal activity, and blood hematological parameters in the 0.01–0.04% TP groups. According to these findings, TPs could be a useful dietary supplement for raising the antioxidant status, growth parameters, haemato-immunological response, and whole-body composition of coho salmon fish. [ABSTRACT FROM AUTHOR]

The amount of by-products/waste in the fish industry is roughly 50%. Fish bones could be used to produce nanoparticles, which may have potential use in the food industry as a novel calcium source and at the same time, contribute to reduce waste production. The objective of this study was to evaluate the bioavailability of nano-size salmon fish bone particles compared to micro-size salmon fish bone particles, and calcium carbonate. The study was carried out in 21–28-day-old C57BL/6 male mice fed for 21 days with the experimental diets. The groups were as follows: CaCO3 0.5% Ca (CN 0.5); CaCO3 1.0% Ca (CN 1.0); salmon fish bone (SFB) microparticles 0.5% Ca (MP 0.5); SFB microparticles 1.0% Ca (MP 1.0); SFB nanoparticles 0.5% Ca (NP 0.5); and SFB nanoparticles 1.0% Ca (NP 1.0). Calcium bioavailability, defined as the percent calcium in femur showed an increasing trend from CN 0.5 to NP 1.0 group. According to ANCOVA, the greatest Ca content was observed in the NP 1.0 group compared with all groups but NP 0.5. In conclusion, in a murine model, salmon fish bone nanoparticles present higher calcium bioavailability than salmon fish bone microparticles, and both, in turn, have better bioavailability than calcium carbonate. [ABSTRACT FROM AUTHOR]

Lumpfish (Cyclopterus lumpus) are used as cleaner fish in salmon aquaculture to treat sea lice. However, after 18–24 months and reaching 0.4–0.6 kg, the fish is removed from the salmon cage and usually discarded, which raises social, economic, and environmental challenges, as well as ethical concerns. This paper assesses the viability of marketing lumpfish as food by exploring possible products that can be made from the fish in Vietnamese cuisine, and understanding the stakeholder's perception and acceptance of the fish. We used a customer co-creation method to investigate market potential, sending a sample of 45 kg of frozen and whole lumpfish from Norway to Vietnam. Researchers, industrial stakeholders, restaurant chefs, and household consumers collaborated to discuss, process, cook, and taste the fish, and the evaluations were assessed before and after consumption. More than 10 Vietnamese dishes were identified as possible use for lumpfish, including grilled, fried, sour soup, hotpot, and several value-added products. Household consumers and restaurant buyers evaluated the fish positively in terms of sensory quality (taste, color, flavor, size, and texture), but the rough skin and sharp thorn are negative aspects. Individual consumers accept the fish and were willing to buy it if the price is reasonable. In contrast, industrial stakeholders evaluated the lumpfish less favorably, citing its soft and mushy texture, sticky smell, and very low fillet-recovery-ratio (only 15.9% of skinless fillet and 16.7% of kama can be obtained from whole-defrosted lumpfish). They also found that the taste of the fish was not delicious and bitter in some value-added products. In addition, this study found that the information relating to lumpfish as a cleaner fish is not an issue in the Vietnamese context. [ABSTRACT FROM AUTHOR]

Purpose: Fishes like Mackerel, salmon and trout have been a great inspiration for effective underwater propulsion. Their propulsion mechanism involves flapping the posterior body members. Fish actively modify the stiffness of these members to meet various swimming requirements. Methods: In this study, two posterior body parts of a fish, namely the peduncle and the caudal fin, are analysed for biomimetic propulsion. These members are modelled as Euler–Bernoulli beams and appropriate stiffeners are introduced at their joints. The surrounding fluid domain is modelled using potential flow theory. The fluid–structure interaction results in an added-mass effect. The mean propulsive thrust depends on the tip velocity of the flapping structure, and hence, it could be maximised by increasing the peak response bandwidth. Results: This work presents the sensitive range of the stiffness parameters, such as the stiffness of the members and the coupling stiffeners, which are essential for thrust augmentation. The resonance of the system is discussed for various peduncle–caudal dimensions observed in salmon fish. Conclusion: The study presents the theoretical modelling of peduncle–fin-inspired coupled structures for underwater propulsion. The results highlight the potential for improving thrust by appropriately adjusting the structural stiffness parameters. [ABSTRACT FROM AUTHOR]

Conservation planners often rely on heuristic indices when challenged with prioritizing potential projects under a constrained budget. This paper presents a comparative analysis of several prioritization indices (PIs) of culvert fish passage barriers, which can contribute to declines in anadromous fish populations. A federal injunction requires Washington state to restore 90% of habitat blocked by state‐owned culverts by 2030, prompting the development of numerous PIs, by various entities (i.e., counties, cities) within the injunction area. Our comparative analysis of PIs within the injunction Case Area investigates their ability to distinguish between barriers, their transferability in terms of scoring metrics, how scoring weights differ, and the preferences implied thereby. We document the use of six distinct PI methods by 10 entities and find that some PIs used many shared metrics, whereas others used a high percentage of unique metrics that would be difficult to replicate outside the entity's jurisdiction. Although habitat potential, habitat quantity, and connectivity were considered across all PIs, we found a high level of variation in terms of the metric weights. Our methods can be employed in other geographies or for other restoration PI planning efforts, and our results may facilitate the development and refinement of future PIs. [ABSTRACT FROM AUTHOR]

Fishing has the potential to influence the life‐history traits of exploited populations. However, our understanding of how fisheries can induce evolutionary genetic changes remains incomplete. The discovery of large‐effect loci linked with ecologically important life‐history traits, such as age at maturity in Atlantic salmon (Salmo salar), provides an opportunity to study the impacts of temporally varying fishing pressures on these traits. A 93‐year archive of fish scales from wild Atlantic salmon catches from the northern Baltic Sea region allowed us to monitor variation in adaptive genetic diversity linked with age at maturity of wild Atlantic salmon populations. The dataset consisted of samples from both commercial and recreational fisheries that target salmon on their spawning migration. Using a genotyping‐by‐sequencing approach (GT‐seq), we discovered strong within‐season allele frequency changes at the vgll3 locus linked with Atlantic salmon age at maturity: fishing in the early season preferentially targeted the vgll3 variant linked with older maturation. We also found within‐season temporal variation in catch proportions of different wild Atlantic salmon subpopulations. Therefore, selective pressures of harvesting may vary depending on the seasonal timing of fishing, which has the potential to cause evolutionary changes in key life‐history traits and their diversity. This knowledge can be used to guide fisheries management to reduce the effects of fishing practices on salmon life‐history diversity. Thus, this study provides a tangible example of using genomic approaches to infer, monitor and help mitigate human impacts on adaptively important genetic variation in nature. [ABSTRACT FROM AUTHOR]

This study was conducted on salmon(Atlantic salmon)Salmo salar products imported to Iraq, which are a whole fish removed head and tail, fillets, rings, fingers and cubes evaluating of the sensory characteristics of these products and determining their suitability for human consumption. The products were obtained from King of Fish and Meat company ( K.F. M.), the exclusive agent in Iraq, and all products were within one meal and date, and the validity of each product was from 5/10/2021 to 4/7/2022. Results were as follows :The results of the sensory characteristics (color, flavor, freshness, juiciness, general acceptance) showed asignificant differences (p≤0.05) among salmon fish products, but they did not reach the limits of rejection. The results above of sensory tests of imported salmon fish products showed that they are suitable for human consumption and proved that they are within acceptable limits after comparing them with research and standard specifications. [ABSTRACT FROM AUTHOR]

Resource user compliance is a key element in effective fisheries management. Herein, we examine two decades of enforcement records pertaining to Atlantic salmon from Newfoundland and Labrador, Canada. Illegal incidents were negatively correlated with the number of licensed anglers but not salmon abundance. Over two decades, illegal incidents declined by 66%, even after correcting for the positive relationship between enforcement effort and illegal incidents. This decline was primarily driven by a 67% reduction in netting and jigging‐related violations, which were likely to impose the highest levels of mortality on adult salmon among violations examined. Additionally, illegal incidents and violation types did not increase as a result of management changes. While Newfoundland and Labrador remains one of the last strongholds for Atlantic salmon, we encourage other jurisdictions to monitor fisheries compliance to better understand the social‐ecological landscape that is crucial to supporting healthy fisheries. [ABSTRACT FROM AUTHOR]

Many fish species depend on migration for various parts of their life cycle. Well‐known examples include diadromous fish such as salmon and eels that need both fresh water and salt water to complete their life cycle. Migration also occurs within species that depend only on fresh water. In recent decades, anthropogenic pressures on freshwater systems have increased greatly, and have resulted, among other effects, in drastic habitat fragmentation. Fishways have been developed to mitigate the resulting habitat fragmentation, but these are not always effective. To improve fishway efficiency, the variety of navigation cues used by fish must be better understood: fish use a multitude of sensory inputs ranging from flow variables to olfactory cues. The reaction of a fish is highly dependent on the intensity of the cue, the fish species involved, and individual traits. Recently developed monitoring technologies allow us to gain insights into different combinations of environmental and physiological conditions. By combining fish behavioural models with environmental models, interactions among these components can be investigated. Several methods can be used to analyse fish migration, with state‐space models, hidden Markov models, and individual‐based models potentially being the most relevant since they can use individual data and can tie them to explicit spatial locations within the considered system. The aim of this review is to analyse the navigational cues used by fish and the models that can be applied to gather knowledge on these processes. Such knowledge could greatly improve the design and operation of fishways for a wider range of fish species and conditions. [ABSTRACT FROM AUTHOR]

Saprolegniosis is a major destructive disease in freshwater aquaculture. The destructive economic impact of saprolegniosis on freshwater aquaculture necessitates further study on the range of Saprolegnia species within Atlantic salmon fish farms. This study undertook a thorough analysis of a total of 412 oomycete and fungal isolates that were successfully cultured and sequenced from 14 aquaculture sites in Scotland across a two-year sampling period. An ITS phylogenetic analysis of all isolates was performed according to whether they were isolated from fish or water samples and during enzootic or epizootic periods. Several genera of oomycetes were isolated from sampling sites, including Achlya, Leptolegnia, Phytophthora, and Pythium, but by far the most prevalent was Saprolegnia, accounting for 66% of all oomycetes isolated. An analysis of the ITS region of Saprolegnia parasitica showed five distinct phylotypes (S2–S6); S1 was not isolated from any site. Phylotype S2 was the most common and most widely distributed phylotype, being found at 12 of the 14 sampling sites. S2 was overwhelmingly sampled from fish (93.5%) and made up 91.1% of all S. parasitica phylotypes sampled during epizootics, as well as 67.2% of all Saprolegnia. This study indicates that a single phylotype may be responsible for Saprolegnia outbreaks in Atlantic salmon fish farms, and that water sampling and spore counts alone may be insufficient to predict Saprolegnia outbreaks in freshwater aquaculture. [ABSTRACT FROM AUTHOR]

Information on trends in Russian-origin sockeye salmon abundance and suggestions on its possible catch in the medium term are discussed. The average catch over the period from 1907 to 2022 was about 27 000 t. The catches of sockeye and pink, sockeye, and chum salmon from 1971 to 2022 have been correlated. Calculation scenarios of Pacific salmon forecast catches of Russian origin up to 2035 are presented. Two periods of low abundance of Asian sockeye, from the beginning of observations to 1927 and from 1965 to 2001, and also two periods of high abundance, from 1928 to 1964 and from 2002 up to the present time are noted. The length of the recorded periods was about 35–37 years. The complete cycle of the dynamics of the sockeye salmon population of Russian origin takes about 70–75 years. Trends in sockeye salmon population dynamics and Russian origin Pacific salmon are very similar on the whole. It can be assumed that until the late 2020s and early 2030s, the Russian-origin sockeye salmon average catch will be at least 35 000 t. [ABSTRACT FROM AUTHOR]

Some parameters of abundance dynamics for the Pacific salmon species breeding in Russian waters are clarified and their possible catch on a medium-term scale estimated. The average annual catch for the 1907–2022 period was approximately 250 000 t. A complete cycle from the minimum values on the curves of one low-abundance period to the respective parameters of another period took approximately 72 years; from the relative maxima of one high-abundance period to another took 75 years. The duration of the high-abundance period was almost 35 years; the low-abundance period was almost 40 years. Taking various uncertainties into account, the periods of high and low abundance were approximately equivalent and remained within a relatively stable range from 35 to 40 years. Most of the high-catch seasons occurred in the odd-numbered years. Dominants usually changed during the periods of increase in Pacific salmon abundance. The average annual catches are expected to be higher than 250 000 t in the second half of the 2020s and the first half of the 2030s. Catch sizes are unlikely to be lower than 200 000 t even in the least productive years. In the final part of the high-abundance period, the raw material base of the Russian salmon fishery does not provide conditions for profitable operations at most of the fishing sites allotted for commercial harvesting. [ABSTRACT FROM AUTHOR]

Aiming at the strong spot noise caused by the reflection of meat slices in fish image with foreign matters that collected by ordinary camera or Single Lens Reflex (SLR) camera, we proposed an improved wavelet transform and bilateral filtering algorithm to reduce the noise of image. In this paper, our algorithm absorbed the advantages of wavelet threshold de‐noising algorithm and bilateral filtering algorithm, the wavelet threshold de‐noising algorithm being used for high frequency components and bilateral filtering being used for low frequency components, which not only achieved the effect of eliminating noise and weakening light spot, but also protected the details of the image. In the experiment, in order to verify the effectiveness of the proposed algorithm, we used the traditional bilateral filtering, Gaussian filtering and median filtering algorithms to process 500 salmon fish images which had residual fishbone, respectively. Since the original image itself was a noisy image, it was impossible to evaluate the noise reduction effect by using an algorithm that requires a noiseless image as a reference image, so we used five methods to evaluate the quality of the image processed by each algorithm, which were Blind/Referenceless Image Spatial QUality Evaluator (BRISQE), Cumulative Probability of Blur Detection (CPBD), variance, image entropy, and operation speed. Among them, BRISQE and CPBD could quantitatively reflect the overall quality of the image, the lower the BRISQE score or the higher the CPBD score, the better the quality of the image. Compared with other algorithms, the BRISQE score and CPBD score of the image processed by our algorithm were the best, with the average scores reaching 20.65 and.8421, respectively. Experimental results showed that the improved algorithm in this paper can effectively eliminate this kind of strong spot noise. The processed image has achieved better visual effect in both subjective and objective level. [ABSTRACT FROM AUTHOR]

North‐east Pacific juvenile salmon and forage fishes, including the endangered salmon species Chinook (Oncorhynchus tshawytscha), coho (Oncorhynchus kisutch), chum (Oncorhynchus keta), and pink (Oncorhynchus gorbuscha), and the forage fishes species of Pacific herring (Clupea pallasi), surf smelt (Hypomesus pretiosus), and sand lance (Ammodytes hexapterus), utilize kelp environments. Many details of the kelp forest ecosystem function for these fishes are lacking.Kelp forests, salmon, and forage fishes are declining precipitously as the global climate shifts and developments along coastal shorelines expand. It is therefore essential to understand kelp forest function for these species.Analysis of 7 years of snorkelling survey videos indicates that both forage fishes and salmon use kelp forests throughout the outmigration season, and that their interactions occur in small and large groups, primarily along the outer edge of kelp beds. Over the course of outmigration, juvenile Chinook and coho salmon encounter sand lance first, followed by smelt and herring. The majority of interactions are intermingling, in which a subset proceed to predation, primarily on herring.It is important to develop and implement specific fishery and habitat conservation measures to preserve and restore these functions. Long‐term research has shown that intact, conserved nearshore habitats function better ecologically than restored habitats, and individual kelp forests can function differently for forage fishes and salmon. Therefore, conservation plans should be developed to conserve wild kelp forests which are documented to provide ecosystem function for salmon and forage fishes, by protecting them from various development impacts, including dredging, filling, and water‐quality decline.Coastal restoration is often only successful when ecosystem‐limiting factors that result in a loss of habitat are resolved. Kelp forest restoration, therefore, should be prioritized for regions of known high historical kelp forest importance, with restoration actions focused on correcting the limiting factors that caused loss and/or degradation. [ABSTRACT FROM AUTHOR]

Atlantic salmon fishing in northern Fennoscandia is part of controversial ecological, sociocultural, legal, and political questions. This paper presents a study of landscape justice as perceived by stakeholders who practice, manage, and govern traditional, household, and recreational salmon fishing on northern Finland's border rivers, Tornio (Torne) and Teno (Tana). The concept of landscape justice is analysed through the lens of distributive, substantive, procedural, and recognition forms of justice. The data are based on semi-structured stakeholder interviews (N = 15). A qualitative content analysis of the data based on the forms of justice reveals that salmon are associated with diverse environmental, economic, and sociocultural values of the landscape. The study results show the current state governance mode of salmon fishing causes landscape injustice manifesting, in particular, as an unequal distribution of risks and benefits regarding fishing governance and its challenges. There is unclear legislation for Tornio. Landscape justice is violated by regulations causing unclear case law for Teno on the ownership of land or water and related fishing restrictions, as well as a lack of possibilities for local tourist entrepreneurs and household fishermen to participate in decision making. Governmental decisions are mainly based on the overall ecological status of salmon populations at the expense of local variations or the recognition and systemic evaluation of sociocultural and local economic values of the landscape. The results indicate a need for national and cross-border policy decisions to include sociocultural and economic aspects of Atlantic salmon fishing to guide movement towards more just environmental governance. [ABSTRACT FROM AUTHOR]

A key challenge in many regulated rivers is to define adequate flow levels to protect aquatic organisms. Provisioning of suitable flow can be pivotal bottlenecks for fishes such as salmon and trout that use the riverbed as an incubation habitat. Additionally, the locations where females spawn will define the probability that embryos will be dewatered during the incubation period in a regulated flow regime. We investigated the water flow, dewatering, and incubation mortality in Atlantic salmon and brown trout in natural nests over 19 years in the regulated Bjoreio River in western Norway. During the study period, different flow strategies were applied to mitigate the dewatering of incubating salmon and trout embryos. Average survival in nests sampled in late winter ranged from 54% to 92% among years and was significantly correlated with the minimum water flow occurring during the incubation period. Mortality was significantly higher in nests in shallow areas, reflecting nests exposed to dewatering. The results demonstrate a strong link between incubation mortality and managed flow regimes for river spawning salmonids. Using detailed information on the nest location and incubation mortality, we estimate minimum flow requirements for this river and demonstrate an approach to effectively mitigate the impact of river regulations on embryo survival in Atlantic salmon and brown trout. [ABSTRACT FROM AUTHOR]

In this study, we develop a dynamic Inverse Almost Ideal Demand System model to derive own- and cross-price flexibilities for wild-caught fish, Australian farmed salmon and imports of fresh and frozen fish. We find that the growth of fresh fish imports and Australian farmed salmon production have both individually had a significant negative impact on the prices received for Australian wild-caught species, particularly the lower valued species. Continued growth in imports and the farmed salmon sector may negatively impact prices and hence profitability in wild-caught fisheries in Australia in the future. [ABSTRACT FROM AUTHOR]

The status of Newfoundland and Labrador (NL) Atlantic Salmon populations are assessed relative to two reference points, defined on the basis of egg depositions, which separate three stock status zones (critical, cautious and healthy) as per the Fishery Decision-Making Framework Incorporating the Precautionary Approach. These reference points, the Limit Reference Point (LRP) and Upper Stock Reference (USR) point are set at 100% and 150% of the previously defined river-specific conservation egg deposition rate, respectively. In 2018, the status of Atlantic Salmon stocks within the NL Region (Salmon Fishing Areas 1-14B) was assessed using data collected from twenty-two rivers using a combination of salmon counting facilities (fishways and counting fences) and in-river snorkel surveys. Atlantic Salmon smolts migrating to sea were counted on five rivers in Newfoundland. The status of each monitored river is described by the designated stock status zone, % LRP achieved, and both short and long term trends in total adult salmon returns, smolt production and marine survival rates. Estimates of retained salmon in the 2018 recreational fishery were down by 70% and 58% compared to the previous generation averages in Newfoundland and Labrador, respectively. Labrador Food Social and Ceremonial (FSC) and subsistence fisheries harvests were estimated at 12,843 salmon in 2018 (8,762 small, 4,081 large), 7% less than the previous generation average. Of the twenty-two rivers monitored in 2018, one river was not included in the assessment due to an incomplete salmon count. Of the twenty-one other monitored rivers, sixteen had information on total returns over the previous generation (short term comparisons) and fifteen had information over the previous three generations (long term comparisons). Compared to the previous generation, total returns in 2018 were higher on three of four monitored rivers in Labrador and lower on five of twelve monitored rivers in Newfoundland. Compared to the previous three generations, total returns in 2018 were lower on one of four monitored rivers in Labrador and on five of eleven monitored rivers in Newfoundland. Conservation egg requirements were below the river-specific LRP (in the critical zone) on ten assessed rivers, between the LRP and USR on three assessed rivers, and above the river-specific USR on eight assessed rivers in the NL Region. Marine smolt survival is considered to be a major factor limiting the abundance of Atlantic Salmon within the NL Region. Smolt to adult survival of the 2018 smolt class ranged from <1% for Conne River to 9.3% for Western Arm Brook. [ABSTRACT FROM AUTHOR]

To support preparation of a forthcoming Committee on the Status of Endangered Wildlife in Canada (COSEWIC) review, this report assembles data on Atlantic Salmon (Salmo salar) biology, demographics, habitat, and threats for Prince Edward Island (PEI) (Salmon Fishing Area 17). Historical accounts indicate that the original PEI Atlantic Salmon population was dominated by late-run and large (= 63 cm) fish. These characteristics are retained in small rivers. At least 38,826,353 Atlantic Salmon have been stocked in PEI in 1880 - 2020, mostly in larger rivers. The proportion of early-run and small Salmon has been increased in larger rivers by the stocking of fish intended to increase summer angling opportunities. Sea ages of returning adults are generally one year for small Salmon and two years for large Salmon. Return rates for fish of hatchery origin range from 0.5 to 5.9%. Data on return rates of naturally spawned fish are unavailable. In the Morell River, PEI's traditionally most important Salmon river, mean fecundity is 3,143 eggs for small Salmon and 4,963 eggs for large Salmon. The egg phase (1 year), juvenile phase (mean 2.32 years), and sea phase (mean 1.77 years) sum to 5.09 years, which is the mean generation time of the population. The typical early life history pattern of PEI Atlantic Salmon occurs in rivers, with eggs hatching as fry, fry developing into parr, and parr turning into smolts which leave on marine migrations. However, some juvenile males mature precociously, and some parr occupy ponds and estuaries. The ancestral trait of late-run and large returnees is shared by Atlantic Salmon in southeast New Brunswick and northern Nova Scotia. Genetic data on Salmon in stocked rivers suggest an affinity with Salmon in a broad geographic area centred in the southern Gulf of St. Lawrence. However, genetic samples from two small rivers in northeastern PEI clustered with each other but did not show affinities with samples from elsewhere in Canada. Redd counts for the period 1990 - 2019 showed rising trends in four rivers and falling trends in five rivers. Redd counts for the period 2004 - 2019 showed rising trends in 13 rivers and falling trends in six rivers. Seventy-one PEI rivers are large enough that they probably supported Atlantic Salmon populations in pristine times. For 2000 - 2019, juvenile electrofishing and redd surveys detected Atlantic Salmon at least once in 40 rivers, but detected Atlantic Salmon in every monitored year in only 12 rivers. The spawning population of Atlantic Salmon on PEI is estimated at 717, based on redd counts. Sediment deposition on spawning and rearing habitat is a major threat to Atlantic Salmon on PEI. Additional threats include pesticide-related fish kills, water extraction for municipal and irrigation purposes, climate change leading to more frequent droughts and higher water temperatures, fish passage impairment by dams (including beaver Castor canadensis dams), and competition with non-native Rainbow Trout (Oncorhynchus mykiss). [ABSTRACT FROM AUTHOR]

In support of the Committee on the Status of Endangered Wildlife in Canada's (COSEWIC) reassessment of Atlantic Salmon (Salmo salar), this document updates information and analyses for Atlantic Salmon in Salmon Fishing Area (SFA) 16 since the first review in 2010. The 39 Salmon rivers in SFA 16 are included among the rivers that COSEWIC first identified in the Gaspé-Southern Gulf of St. Lawrence Designatable Unit (DU). The largest runs of Atlantic Salmon in SFA 16 return to the Miramichi River where monitoring programs have been conducted annually since the 1950s to collect biological information on the stock and to estimate the size of the population. Several indices of abundance for adult Salmon in the Miramichi River were reviewed and all showed declines over the time series of information available including the last 16-year period which is the equivalent of three generation times for this population. While population estimation has not been attempted in other smaller rivers recently, annual monitoring programs in the Tabusintac, Kouchibouguac, Kouchibouguacis, and Richibucto rivers all indicate that runs of adult Salmon persist in those rivers. The number of adult Salmon returning to SFA 16 were estimated to have peaked at just under 130 thousand fish in 1986 and declined to less than 20 thousand Salmon in 2019, the lowest value of the time series. The rates of change in abundance for adult Salmon in SFA 16 have declined by 43% for the time series and by 68% in the last 16 years (2003-2019). Juvenile Salmon abundance determined from electrofishing surveys also showed declining trends over the last 16 years in the Miramichi River and other smaller rivers of southeastern New Brunswick. Adult and juvenile Salmon from SFA 16 continue to be widely dispersed in the freshwater and marine habitats during their different life cycle phases. Threats to Atlantic Salmon are generally poorly understood and many are likely working together to limit Salmon abundance in SFA 16. [ABSTRACT FROM AUTHOR]

This document presents information on Atlantic Salmon (Salmo salar) for rivers in Salmon Fishing Area 18 (SFA 18; Northumberland Strait Nova Scotia and Western Cape Breton) of relevance to the development of the status report by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC). There are 55 potential Atlantic Salmon rivers in SFA 18. Of these, the Gulf Nova Scotia (GNS) program focuses its monitoring efforts on four index rivers within SFA 18: The Margaree River, West River Antigonish, East River Pictou, and River Philip. For the Margaree River in 2019, the estimated eggs in the returns of small Salmon and large Salmon combined were 3.9 times greater than the lower reference point (LRP) value. The Salmon population has remained above the LRP for the duration of the Margaree monitoring program (1987 to present). However, returns to all rivers in SFA 18 remain below the long-term return average. The principal threats in SFA 18 are: habitat shifting and alteration, extreme temperatures, and droughts, all of which are related to global climate change. [ABSTRACT FROM AUTHOR]

The population living in the coastal region relies heavily on fish as a food source due to their vast availability and low cost. This need has given rise to fish farming. Fish farmers and the fishing industry face serious challenges such as lice in the aquaculture ecosystem, wounds due to injuries, early fish maturity, etc. causing millions of fish deaths in the fish aquaculture ecosystem. Several measures, such as cleaner fish and anti-parasite drugs, are utilized to reduce sea lice, but getting rid of them entirely is challenging. This study proposed an image-based machine-learning technique to detect wounds and the presence of lice in the live salmon fish farm ecosystem. A new equally distributed dataset contains fish affected by lice and wounds and healthy fish collected from the fish tanks installed at the Institute of Marine Research, Bergen, Norway. A convolutional neural network is proposed for fish lice and wound detection consisting of 15 convolutional and 5 dense layers. The proposed methodology has a test accuracy of 96.7% compared with established VGG-19 and VGG-16 models, with accuracies of 91.2% and 92.8%, respectively. The model has a low false and true positive rate of 0.011 and 0.956, and 0.0307 and 0.965 for fish having lice and wounds, respectively. [ABSTRACT FROM AUTHOR]