The need to transition from traditional single-species fisheries management approaches towards ecosystem-based fisheries management (EBFM), or an ecosystem approach to fisheries, is widely recognised. EBFM is particularly important when considering management actions for economically valuable fisheries for small pelagic forage fish, given their key ecological role. Management strategy evaluation (MSE) is an effective approach to advance the quantitative implementation of EBFM by enabling stakeholders to explore trade-offs among competing ecosystem-related objectives. This paper puts forward six different approaches to advance EBFM with MSE explicity, by taking advantage of data and research already available and by guiding future research. These approaches can be grouped into those which (i) involve the operating model and/or link directly to the operating model while potentially providing additional performance metrics to evaluate ecosystem objectives, (ii) can be incorporated into the performance metrics, and (iii) involve the harvest control rule of the management procedure. This review demonstrates that immediate steps can be taken to implement EBFM targeted at quantitative tactical management, even without a complex, data-rich ecosystem operating model.
{"title":"Explicitly Incorporating Ecosystem-Based Fisheries Management into Management Strategy Evaluation, with a focus on Small Pelagics","authors":"Carryn Lee de Moor","doi":"10.1139/cjfas-2023-0092","DOIUrl":"https://doi.org/10.1139/cjfas-2023-0092","url":null,"abstract":"The need to transition from traditional single-species fisheries management approaches towards ecosystem-based fisheries management (EBFM), or an ecosystem approach to fisheries, is widely recognised. EBFM is particularly important when considering management actions for economically valuable fisheries for small pelagic forage fish, given their key ecological role. Management strategy evaluation (MSE) is an effective approach to advance the quantitative implementation of EBFM by enabling stakeholders to explore trade-offs among competing ecosystem-related objectives. This paper puts forward six different approaches to advance EBFM with MSE explicity, by taking advantage of data and research already available and by guiding future research. These approaches can be grouped into those which (i) involve the operating model and/or link directly to the operating model while potentially providing additional performance metrics to evaluate ecosystem objectives, (ii) can be incorporated into the performance metrics, and (iii) involve the harvest control rule of the management procedure. This review demonstrates that immediate steps can be taken to implement EBFM targeted at quantitative tactical management, even without a complex, data-rich ecosystem operating model.","PeriodicalId":9515,"journal":{"name":"Canadian Journal of Fisheries and Aquatic Sciences","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134947655","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Martin Simonson, Michael J Weber, Audrey L. McCombs, Andrew R Annear
Catch per unit effort (CPUE) is used as an index of fish abundance under the premise that changes in CPUE result from changes in true density. However, catchability may also vary based on environmental conditions that affect observed CPUE. We developed a hierarchical model for estimating common carp ( Cyprinus carpio) and bigmouth buffalo ( Ictiobus cyprinellus) relative abundance with electrofishing survey data from six shallow lakes in northwest Iowa, USA, between 2018 and 2020. Common carp catchability was negatively associated with lake perimeter but unrelated to lake surface area, water depth, Secchi depth, temperature, and month of sampling. Bigmouth buffalo catchability was negatively associated with Secchi depth and water temperature and unrelated to other environmental variables. Hierarchical model posterior distributions of bigmouth buffalo density were less precise than Schnabel estimates, whereas common carp posterior distribution abundance estimates were more precise than Schnabel estimates. Our results indicate that hierarchical models can be a viable substitute for labor-intensive capture–mark–recapture methods to estimate unknown latent variables like relative abundance, and could be applied to other species, sampling gears, and management frameworks.
{"title":"Hierarchical model to predict Common Carp and Bigmouth Buffalo abundance from electrofishing data","authors":"Martin Simonson, Michael J Weber, Audrey L. McCombs, Andrew R Annear","doi":"10.1139/cjfas-2023-0017","DOIUrl":"https://doi.org/10.1139/cjfas-2023-0017","url":null,"abstract":"Catch per unit effort (CPUE) is used as an index of fish abundance under the premise that changes in CPUE result from changes in true density. However, catchability may also vary based on environmental conditions that affect observed CPUE. We developed a hierarchical model for estimating common carp ( Cyprinus carpio) and bigmouth buffalo ( Ictiobus cyprinellus) relative abundance with electrofishing survey data from six shallow lakes in northwest Iowa, USA, between 2018 and 2020. Common carp catchability was negatively associated with lake perimeter but unrelated to lake surface area, water depth, Secchi depth, temperature, and month of sampling. Bigmouth buffalo catchability was negatively associated with Secchi depth and water temperature and unrelated to other environmental variables. Hierarchical model posterior distributions of bigmouth buffalo density were less precise than Schnabel estimates, whereas common carp posterior distribution abundance estimates were more precise than Schnabel estimates. Our results indicate that hierarchical models can be a viable substitute for labor-intensive capture–mark–recapture methods to estimate unknown latent variables like relative abundance, and could be applied to other species, sampling gears, and management frameworks.","PeriodicalId":9515,"journal":{"name":"Canadian Journal of Fisheries and Aquatic Sciences","volume":"100 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135549152","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sarah K. Gaichas, James Gartland, Brian E Smith, Anthony Wood, Elizabeth Ng, Michael Celestino, Katie Drew, Abigail S. Tyrell, James T Thorson
Changing distribution and abundance of small pelagic fishes may drive changes in predator distributions, affecting predator availability to fisheries and surveys. However, small pelagics are difficult to survey directly, so we developed a novel method of assessing the aggregate abundance of 21 small pelagic forage taxa via predator stomach contents. We used stomach contents collected from 22 piscivore species captured by multiple bottom trawl surveys within a Vector Autoregressive Spatio-Temporal (VAST) model to assess trends of small pelagics on the Northeast US shelf. The goal was to develop a spatial “forage index” to inform survey and/or fishery availability in the western North Atlantic bluefish (*Pomatomus saltatrix*) stock assessment. This spatially-resolved index compared favorably with more traditional design-based survey biomass indices for forage species well sampled by surveys. However, our stomach contents-based index better represented smaller unmanaged forage species that surveys are not designed to capture. The stomach-based forage index helped explain bluefish availability to the recreational fishery for stock assessment, and provided insight into pelagic forage trends throughout the regional ecosystem.
{"title":"Assessing small pelagic fish trends in space and time using piscivore stomach contents","authors":"Sarah K. Gaichas, James Gartland, Brian E Smith, Anthony Wood, Elizabeth Ng, Michael Celestino, Katie Drew, Abigail S. Tyrell, James T Thorson","doi":"10.1139/cjfas-2023-0093","DOIUrl":"https://doi.org/10.1139/cjfas-2023-0093","url":null,"abstract":"Changing distribution and abundance of small pelagic fishes may drive changes in predator distributions, affecting predator availability to fisheries and surveys. However, small pelagics are difficult to survey directly, so we developed a novel method of assessing the aggregate abundance of 21 small pelagic forage taxa via predator stomach contents. We used stomach contents collected from 22 piscivore species captured by multiple bottom trawl surveys within a Vector Autoregressive Spatio-Temporal (VAST) model to assess trends of small pelagics on the Northeast US shelf. The goal was to develop a spatial “forage index” to inform survey and/or fishery availability in the western North Atlantic bluefish (*Pomatomus saltatrix*) stock assessment. This spatially-resolved index compared favorably with more traditional design-based survey biomass indices for forage species well sampled by surveys. However, our stomach contents-based index better represented smaller unmanaged forage species that surveys are not designed to capture. The stomach-based forage index helped explain bluefish availability to the recreational fishery for stock assessment, and provided insight into pelagic forage trends throughout the regional ecosystem.","PeriodicalId":9515,"journal":{"name":"Canadian Journal of Fisheries and Aquatic Sciences","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135549095","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Peter-John F. Hulson, Benjamin C Williams, Meaghan D. Bryan, Jason Conner, Matthew R Siskey
Unavoidable survey effort reduction has become a reality that must be accounted for in fisheries stock assessment. In addition, negative consequences to survey staff health due to repetitive motion injuries are becoming increasingly costly for managing agencies. In this study, we evaluated the outcomes of reductions in age and length data used in fisheries stock assessment models. The main goal was to determine whether sampling can be reduced to a level that does not excessively increase data uncertainty, yet provides a reduction in repetitive motions that can cause injury to survey staff. We found that reducing length sampling to a maximum of 100–150 fish sampled per haul (either sex-specific or combined sex) provides length composition data for which the uncertainty is not appreciably increased, and it has minimal effect on the uncertainty in age composition data that is subsequently expanded from this subsampled length frequency data. The method employed here, and the results presented, can aid management agencies to balance the magnitude of data collection and subsequent consequences to fisheries stock assessment models.
{"title":"Reductions in sampling effort for fishery-independent age and length composition: balancing sampling efficiency, data uncertainty, and workforce health","authors":"Peter-John F. Hulson, Benjamin C Williams, Meaghan D. Bryan, Jason Conner, Matthew R Siskey","doi":"10.1139/cjfas-2023-0164","DOIUrl":"https://doi.org/10.1139/cjfas-2023-0164","url":null,"abstract":"Unavoidable survey effort reduction has become a reality that must be accounted for in fisheries stock assessment. In addition, negative consequences to survey staff health due to repetitive motion injuries are becoming increasingly costly for managing agencies. In this study, we evaluated the outcomes of reductions in age and length data used in fisheries stock assessment models. The main goal was to determine whether sampling can be reduced to a level that does not excessively increase data uncertainty, yet provides a reduction in repetitive motions that can cause injury to survey staff. We found that reducing length sampling to a maximum of 100–150 fish sampled per haul (either sex-specific or combined sex) provides length composition data for which the uncertainty is not appreciably increased, and it has minimal effect on the uncertainty in age composition data that is subsequently expanded from this subsampled length frequency data. The method employed here, and the results presented, can aid management agencies to balance the magnitude of data collection and subsequent consequences to fisheries stock assessment models.","PeriodicalId":9515,"journal":{"name":"Canadian Journal of Fisheries and Aquatic Sciences","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134885362","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We examined the physiological performance in the most cosmopolitan coccolithophorid, Emiliania huxleyi, and Gephyrocapsa oceanica, which were treated with 8.3 (AO), 4.6 (MO) and 2.5 (LO) mg L–1 O2 under 400 (AC) and1000 (HC) ppm CO2 conditions. Elevated CO2 decreased the specific growth rate of cells cultured under AO and LO conditions in both species, but it increased the rate in the MO-grown E. huxleyi. Regardless of the CO2 levels, diminished O2 concentration inhibited the growth rate in E. huxleyi while accelerating the rate in G. oceanica. LO reduced the particulate organic carbon (POC) production rate compared to the AO treatment in both species. Additionally, the decrease was higher in the HC cultures than in the AC ones. LO also inhibited the production rate of particulate inorganic carbon (PIC) compared to the AO/AC treatment. Due to a higher reduction in the production rate of PIC than POC, the PIC/POC ratio was decreased in the LO treatment compared to the AO/AC treatment. The current study reveals that low O2 can, individually or in combination with high CO2, considerably affect the physiology of marine photoautotrophic organisms.
{"title":"Decreased calcification to photosynthesis ratio in coccolithophores under reduced O2 and elevated CO2 environment","authors":"Shanying Tong, Dong Xu, Hongjin Qiao, Naihao Ye","doi":"10.1139/cjfas-2023-0073","DOIUrl":"https://doi.org/10.1139/cjfas-2023-0073","url":null,"abstract":"We examined the physiological performance in the most cosmopolitan coccolithophorid, Emiliania huxleyi, and Gephyrocapsa oceanica, which were treated with 8.3 (AO), 4.6 (MO) and 2.5 (LO) mg L–1 O2 under 400 (AC) and1000 (HC) ppm CO2 conditions. Elevated CO2 decreased the specific growth rate of cells cultured under AO and LO conditions in both species, but it increased the rate in the MO-grown E. huxleyi. Regardless of the CO2 levels, diminished O2 concentration inhibited the growth rate in E. huxleyi while accelerating the rate in G. oceanica. LO reduced the particulate organic carbon (POC) production rate compared to the AO treatment in both species. Additionally, the decrease was higher in the HC cultures than in the AC ones. LO also inhibited the production rate of particulate inorganic carbon (PIC) compared to the AO/AC treatment. Due to a higher reduction in the production rate of PIC than POC, the PIC/POC ratio was decreased in the LO treatment compared to the AO/AC treatment. The current study reveals that low O2 can, individually or in combination with high CO2, considerably affect the physiology of marine photoautotrophic organisms.","PeriodicalId":9515,"journal":{"name":"Canadian Journal of Fisheries and Aquatic Sciences","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136307643","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Shay O'Farrell, Larry Perruso, James N. Sanchirico, Iliana Chollett
Mapping the economic value of the ocean is pivotal to understand how marine ecosystems contribute to human well-being and to support fisheries management. We present a framework to analyse fisheries data and map fishing revenues by linking Vessel Monitoring System (VMS) information to logbooks and observer data. We provide a detailed step-by-step methodology and describe different approaches available to fulfill each step, with special notes for the processing of real-world messy data. The framework consists of six processing steps: (1) identifying the target fishery and subsetting VMS data, (2) extracting relevant variables, (3) linking observer and VMS data, (4) identifying fishing activity, (5) linking VMS and logbook data, and (6) extracting derived variables and mapping revenue back to the communities that extracted the resources. Building this framework opens a broad range of applications including marine spatial planning, rapid response analyses, high-resolution stock assessments, and spatially explicit-socioeconomic analyses. We demonstrate the framework in the reef fishery of the Gulf of Mexico, where spatial planning for aquaculture is currently underway.
{"title":"Linking real world fisheries datasets for mapping of revenue from fishing grounds to dependent communities","authors":"Shay O'Farrell, Larry Perruso, James N. Sanchirico, Iliana Chollett","doi":"10.1139/cjfas-2023-0123","DOIUrl":"https://doi.org/10.1139/cjfas-2023-0123","url":null,"abstract":"Mapping the economic value of the ocean is pivotal to understand how marine ecosystems contribute to human well-being and to support fisheries management. We present a framework to analyse fisheries data and map fishing revenues by linking Vessel Monitoring System (VMS) information to logbooks and observer data. We provide a detailed step-by-step methodology and describe different approaches available to fulfill each step, with special notes for the processing of real-world messy data. The framework consists of six processing steps: (1) identifying the target fishery and subsetting VMS data, (2) extracting relevant variables, (3) linking observer and VMS data, (4) identifying fishing activity, (5) linking VMS and logbook data, and (6) extracting derived variables and mapping revenue back to the communities that extracted the resources. Building this framework opens a broad range of applications including marine spatial planning, rapid response analyses, high-resolution stock assessments, and spatially explicit-socioeconomic analyses. We demonstrate the framework in the reef fishery of the Gulf of Mexico, where spatial planning for aquaculture is currently underway.","PeriodicalId":9515,"journal":{"name":"Canadian Journal of Fisheries and Aquatic Sciences","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135487151","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In response to a federal government order, the number of salmon farms operating in the Discovery Islands region declined from eight in 2020, to one in 2022. Over this period, 1627 juvenile pink ( Oncorhynchus gorbuscha) and chum ( Oncorhynchus keta) salmon captured at sites throughout the study area were examined for sea lice. The average number of sea lice per juvenile salmon declined by 96% over the study period. Such a substantial decline was not witnessed in similar samples from the nearby Broughton Archipelago. The decline could not be attributed to chance sampling, and only a small proportion of it was associated with environmental fluctuations.
{"title":"Effect of government removal of salmon farms on sea lice infection of juvenile wild salmon in the Discovery Islands","authors":"Rick Routledge, Alexandra Morton","doi":"10.1139/cjfas-2023-0039","DOIUrl":"https://doi.org/10.1139/cjfas-2023-0039","url":null,"abstract":"In response to a federal government order, the number of salmon farms operating in the Discovery Islands region declined from eight in 2020, to one in 2022. Over this period, 1627 juvenile pink ( Oncorhynchus gorbuscha) and chum ( Oncorhynchus keta) salmon captured at sites throughout the study area were examined for sea lice. The average number of sea lice per juvenile salmon declined by 96% over the study period. Such a substantial decline was not witnessed in similar samples from the nearby Broughton Archipelago. The decline could not be attributed to chance sampling, and only a small proportion of it was associated with environmental fluctuations.","PeriodicalId":9515,"journal":{"name":"Canadian Journal of Fisheries and Aquatic Sciences","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135878106","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Paul J. Askey, Hillary G. M. Ward, Tyler J Weir, Kristen King
Many salmon species are monitored by visual counts of spawners in streams; however, there are few data sets where abundance is known and compared to estimates derived from visual counts. We used spawner fences to obtain known kokanee ( Oncorhynchus nerka) spawner abundance (14 stream-years) on streams that are monitored with annual visual surveys (7 to 9 counts per year) and incorporated similar published data from pink salmon ( Oncorhynchus gorbuscha) (11 stream-years). We investigated the performance of several simplified expansion factor estimation methods with survey life and observer efficiency as unknown nuisance parameters. All visual indices of kokanee and pink salmon spawners from live ground counts were highly correlated to abundance from fence counts ( r 2 ≥ 0.96 and 0.89, respectively). Application of cross-validation on out-of-sample data for both species showed that mean% error could range from 13% to 53% on a previously unsampled stream depending on the species, counting method, and visual index used. Predictive performance metrics were less sensitive to counting frequency than observer efficiency and associated variability, which was influenced by the counting method (aerial versus ground surveys).
{"title":"Comparison of known spawner abundance from fence counts to visual counts for simplified spawner estimation methods.","authors":"Paul J. Askey, Hillary G. M. Ward, Tyler J Weir, Kristen King","doi":"10.1139/cjfas-2023-0111","DOIUrl":"https://doi.org/10.1139/cjfas-2023-0111","url":null,"abstract":"Many salmon species are monitored by visual counts of spawners in streams; however, there are few data sets where abundance is known and compared to estimates derived from visual counts. We used spawner fences to obtain known kokanee ( Oncorhynchus nerka) spawner abundance (14 stream-years) on streams that are monitored with annual visual surveys (7 to 9 counts per year) and incorporated similar published data from pink salmon ( Oncorhynchus gorbuscha) (11 stream-years). We investigated the performance of several simplified expansion factor estimation methods with survey life and observer efficiency as unknown nuisance parameters. All visual indices of kokanee and pink salmon spawners from live ground counts were highly correlated to abundance from fence counts ( r 2 ≥ 0.96 and 0.89, respectively). Application of cross-validation on out-of-sample data for both species showed that mean% error could range from 13% to 53% on a previously unsampled stream depending on the species, counting method, and visual index used. Predictive performance metrics were less sensitive to counting frequency than observer efficiency and associated variability, which was influenced by the counting method (aerial versus ground surveys).","PeriodicalId":9515,"journal":{"name":"Canadian Journal of Fisheries and Aquatic Sciences","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135981900","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ryan A. Harnish, Kenneth D. Ham, John R. Skalski, Richard L. Townsend, Rebecca A. Buchanan
From 2008–2018, acoustic telemetry studies were conducted to evaluate dam passage survival of spring migrant Chinook salmon and steelhead smolts at 7 of the 8 federally operated dams on the lower Snake and Columbia rivers. Data from over 87,000 dam passage events were evaluated using regression modeling to identify the effect of spill operations, environmental conditions, and fish characteristics on powerhouse passage probability. In general, powerhouse passage was positively correlated with discharge, negatively correlated with forebay temperature and fish size, and higher for fish that passed the dam at night and for those that approached from the powerhouse side of the river, suggesting powerhouse passage is largely a function of smolt activity level and swimming ability. As such, spilling large volumes of water to reduce powerhouse passage is likely to be most effective during times of reduced activity and swimming ability (e.g., at night, high flows, cold temperatures). This information can be used to develop dam- and time-specific spill operations that optimize smolt passage, power generation, and other competing demands, such as adult passage.
{"title":"Factors affecting powerhouse passage of spring migrant smolts at federally operated hydroelectric dams of the Snake and Columbia rivers","authors":"Ryan A. Harnish, Kenneth D. Ham, John R. Skalski, Richard L. Townsend, Rebecca A. Buchanan","doi":"10.1139/cjfas-2022-0217","DOIUrl":"https://doi.org/10.1139/cjfas-2022-0217","url":null,"abstract":"From 2008–2018, acoustic telemetry studies were conducted to evaluate dam passage survival of spring migrant Chinook salmon and steelhead smolts at 7 of the 8 federally operated dams on the lower Snake and Columbia rivers. Data from over 87,000 dam passage events were evaluated using regression modeling to identify the effect of spill operations, environmental conditions, and fish characteristics on powerhouse passage probability. In general, powerhouse passage was positively correlated with discharge, negatively correlated with forebay temperature and fish size, and higher for fish that passed the dam at night and for those that approached from the powerhouse side of the river, suggesting powerhouse passage is largely a function of smolt activity level and swimming ability. As such, spilling large volumes of water to reduce powerhouse passage is likely to be most effective during times of reduced activity and swimming ability (e.g., at night, high flows, cold temperatures). This information can be used to develop dam- and time-specific spill operations that optimize smolt passage, power generation, and other competing demands, such as adult passage.","PeriodicalId":9515,"journal":{"name":"Canadian Journal of Fisheries and Aquatic Sciences","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135982245","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kavishka S. Gallage, Alexander Van Nynatten, Nathan K. Lujan, N. Lovejoy, N. Mandrak
Detection of early life stages of fishes is important for understanding life history patterns and critical spawning habitats. When feasible, identifying early life stages of fishes using morphology requires taxonomic expertise and can be challenging, time consuming, and imprecise. In this study, we used DNA metabarcoding to identify egg and larval batch samples from two sites in the species-rich East Sydenham River, Ontario, Canada. We used a two-step PCR metabarcoding approach to amplify a highly variable region of the mitochondrial COI gene from 1075 mixed species batch samples. Amplicon libraries were sequenced with Illumina Mi-seq and the sequencing reads were filtered and assembled using the software package mothur. Barcodes were then classified using a reference library comprised of Great Lakes fishes and potential invaders. In total, 34 species, including three at-risk species and three invasive species, were detected at the two sampling sites. This study shows the potential utility of metabarcoding for detection and identification of early life stage Great Lake fishes.
{"title":"Identifying early life stages of Great Lakes fishes using a metabarcoding approach","authors":"Kavishka S. Gallage, Alexander Van Nynatten, Nathan K. Lujan, N. Lovejoy, N. Mandrak","doi":"10.1139/cjfas-2023-0061","DOIUrl":"https://doi.org/10.1139/cjfas-2023-0061","url":null,"abstract":"Detection of early life stages of fishes is important for understanding life history patterns and critical spawning habitats. When feasible, identifying early life stages of fishes using morphology requires taxonomic expertise and can be challenging, time consuming, and imprecise. In this study, we used DNA metabarcoding to identify egg and larval batch samples from two sites in the species-rich East Sydenham River, Ontario, Canada. We used a two-step PCR metabarcoding approach to amplify a highly variable region of the mitochondrial COI gene from 1075 mixed species batch samples. Amplicon libraries were sequenced with Illumina Mi-seq and the sequencing reads were filtered and assembled using the software package mothur. Barcodes were then classified using a reference library comprised of Great Lakes fishes and potential invaders. In total, 34 species, including three at-risk species and three invasive species, were detected at the two sampling sites. This study shows the potential utility of metabarcoding for detection and identification of early life stage Great Lake fishes.","PeriodicalId":9515,"journal":{"name":"Canadian Journal of Fisheries and Aquatic Sciences","volume":" ","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44976725","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：