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132 Datasets, Page 1 of 14
Inshore Lobster Trawl Survey
An annual trawl survey is conducted in Southwestern Nova Scotia and the Bay of Fundy to assess the lobster stocks in the area. The survey is conducted with the Northeast Fisheries Science Center Ecosystem Survey Trawl (NEST), a small mesh trawl with a cod end liner, which ensures the capture of various sizes of lobster. The dimensions and location of the trawl are monitored and recorded throughout the tow using an electronic trawl mensuration system. In addition, water temperature and depth are also monitored. The target tow length is 1 kilometer which is tracked using an Olex marine charting system. Vessel crew, DFO science staff and a contracted at sea observer work together to perform required tasks and collect all relevant data. Catch from each tow is separated by species, weighed and counted. Length frequency data is collected on select groundfish and crab species and detailed morphometric data is collected on each lobster.PARAMETERS COLLECTED:Set information and profile - includes set date, time depth and locationCatch summary - weight and number caught of each speciesLength Freqeuncies - completed for up to 100 fish for selected speciesLobster Morphological Data - detailed data collected on each lobsterBottom TemperatureTrawl MetricsNOTES ON QUALITY CONTROL:Data is visually verified and double keypunched. On loading to Oracle, data is run through rigorous automated checks to verify data accuracy and integrity.SAMPLING METHODS:The target tow length is 1 kilometer which is tracked using an Olex marine charting system. Vessel crew, DFO science staff and a contracted at sea observer work together to perform required tasks and collect all relevant data. Catch from each tow is separated by species, weighed and counted. Length frequency data is collected on select groundfish and crab species, detailed morphometric data is collected on each lobster. Bottom temperature and trawl metrics are collected for each tow.CITATION LIST:Denton, Cheryl M.. 2020. Maritimes Region Inshore Lobster Trawl Survey Technical Description. Canadian technical reports of fisheries and aquatic sciences (DFO) 3376.
Shrimp catch and bycatch estimates from trawling and trapping in Simoom Sound, British Columbia
These data sets provide information pertaining to shrimp and bycatch estimates associated with otter-trawling and trapping (November, 2000) and beam-trawling (February, 2001) in Simoom Sound. Data sets were compiled and formatted by Meagan Mak.Abstract from report:As part of a project investigating possible modification of marine ecosystems by shrimp trawling and trapping, we obtained information on catches offish, shrimp, prawns , and bycatch organisms as well as weight, sex ratios , egg location and colIateral damage to several species of pandalids and eualids. Focusing on the humpback shrimp (Pandalus hypsinotus), we assessed damage to the rostrum, carapace, abdomen, and tail fan on specimens caught by beam trawling, otter trawling, and trapping. Data are given from a preliminary study conducted in Northumberland Channel in June 2000 and more comprehensive sampling from Simoom Sound in November 2000 and February 2001.
Diversity, Richness, and Biomass Hotspots
This geodatabase includes hotspot maps of 1) nearshore habitat richness, 2) diversity (fish and invertebrates), and 3) biomass (using catch per unit effort of fish and invertebrates), as well as two layers showing the spatial extent of the diversity and biomass hotspot analyses. Full details and methods can be found in the Rubidge et al. 2018 CSAS Research Document 2018/053 available here or at https://waves-vagues.dfo-mpo.gc.ca/Library/40759842.pdf. These data were reviewed as part of a Canadian Science Advisory Secretariat (CSAS) regional peer review process on Nov 1-2, 2017.Habitat Richness Hotspots: Because there are no systematic surveys of nearshore species that span the entire coastline of Northern Shelf Bioregion, the nearshore habitat richness hotspots were developed as a proxy for species diversity in nearshore areas. Habitat richness was calculated from eight habitat features: eelgrass, surfgrass, canopy-forming kelp, estuaries, areas of high rugosity, and hard, mixed, and soft substrate. The number of features within 1 km x 1 km planning units was counted, and hotspots were identified using the Getis-Ord G* tool in ArcGIS. Planning units with Gi_Bin values of 3 (99% confidence) were classified as habitat richness hotspots.Diversity and Biomass Hotspots: Hotspots of fish and invertebrate diversity and biomass were developed as proxies for spatial patterns of productivity in the Northern Shelf Bioregion. Diversity (Shannon diversity) and biomass (kg/hour or count/hook/hour) were calculated from DFO synoptic trawl and outside hard-bottom longline (HBLL) survey catch records. The outside HBLL survey was previously referred to as Pacific Halibut Management Area (PHMA) survey. The synoptic trawl and HBLL surveys have complementary spatial coverage, with the HBLL surveys occurring in more coastal areas (20–260 m) and the synoptic trawl surveys occurring on deeper shelf areas (50–1300 m). Hotspots were identified using the Getis-Ord G* tool in ArcGIS for five separate analyses: fish biomass (trawl), fish diversity (trawl), fish diversity (longline), invertebrate biomass (trawl), and invertebrate diversity (trawl). Using the Minimum Bounding Geometry Tool, convex hull polygons were drawn around groups of hotspot points (Gi_Bin values of 1, 2, or 3; confidence ≥90%) containing 10 or more points. The resulting polygons were then buffered by 1 km and manually edited where needed to exclude any large areas of the polygons that did not include hotspot points.
Vancouver Island Shelf
Fisheries and Oceans Canada (DFO) has been conducting surface water trawl surveys since 1992 in the coastal waters of British Columbia, Washington, Oregon and Alaska and in the high seas of the Gulf of Alaska. These surveys initially focused on determining the migratory patterns (1992-2002) and on the growth and physiology (2003-2016) of juvenile Pacific Salmon. Since 2016, these surveys have been broadened to monitor the whole pelagic ecosystem, retaining a focus on juvenile Pacific Salmon. Surveys have been conducted on the continental shelf of north and west Vancouver Island, included associated sounds and inlets since 1992 and are ongoing. These data are for tows conducted in the continental shelf area for depths shallower than 400 meters.
Oceanic Waters
Fisheries and Oceans Canada (DFO) has been conducting surface water trawl surveys since 1992 in the coastal waters of British Columbia, Washington, Oregon and Alaska and in the high seas of the Gulf of Alaska. These surveys initially focused on determining the migratory patterns (1992-2002) and on the growth and physiology (2003-2016) of juvenile Pacific Salmon. Since 2016, these surveys have been broadened to monitor the whole pelagic ecosystem, retaining a focus on juvenile Pacific Salmon. In this record, surveys were conducted in continental slope waters at depths greater than 400 m out to the Gulf of Alaska, between 1995 and 2011. Periodically, there are tows from surveys conducted in other regions that occurred on the continental slope and they are included here. This set of data also includes data collected during the International Year of Salmon survey in 2022.
Eulachon Migration Study Bottom Trawl Surveys - North
Catch, effort, location (latitude and longitude), and associated biological data from the Eulachon Migration Study Bottom Trawl surveys - North on the coast of British Columbia.Introduction:The Eulachon Migration Study Bottom Trawl survey - North (Eul-N) is part of the in the Eulachon Migration Study Bottom Trawl survey series and took place on the coast of British Columbia. The other survey in this series is the Eulachon Migration Study Bottom Trawl survey –South (Eul-S).The Eulachon Migration Study Bottom Trawl survey - North (Eul-N) was conducted monthly from July 2018 to March 2019 and was funded by the Fisheries and Oceans Canada (DFO) National Rotational Survey Fund.The objective of this survey was to learn about the distribution, ecology, and migration times of Eulachon into the Nass and Skeena rivers by observing their spatial and temporal occurrence and biological condition over a wide survey region and over several months. This survey follows a random block design in a targeted depth range of 80 – 300 metres. The sampling units were 2 km by 2 km blocks. Fishing was conducted using the Canadian Coast Guard Research Vessel Neocaligus to tow an American shrimp trawl net (Cantrawl Nets Ltd., Richmond, BC). The horizontal opening of the polypropylene net was estimated to be 34 to 37 feet (10 to 11 m), while the center of the opening had a vertical height of approximately 7 to 9 feet (2 to 3 m). A 0.4” (10 mm) liner was used in the codend. The net was configured with roller gear and 72” (1.8 m) Thyboron Type 2 trawl doors. Tow duration was typically 5 minutes. The standard hours of fishing were 0800 to 1700 hours, depending on sunrise and sunset in winter months.The Eulachon Migration Study Bottom Trawl survey – North was conducted by the Department of Fisheries and Oceans Canada (DFO). This survey fished mainly in Chatham Sound with sets in Hecate Strait and Portland Inlet including Pacific Fishery Management areas (PFMA’s) 3, 4, and 104.Effort:This table contains information about the survey trips and fishing events (trawl tows/sets) that are part of this survey series. Trip-level information includes the year the survey took place, a unique trip identifier, the vessel that conducted the survey, and the trip start and end dates (the dates the vessel was away from the dock conducting the survey). Set-level information includes the date, time, location, and depth that fishing took place, as well as information that can be used to calculate fishing effort (duration) and swept area. All successful fishing events are included, regardless of what was caught.Catch:This table contains the catch information from successful fishing events. Catches are identified to species or to the lowest taxonomic level possible. Most catches are weighed, but some are too small (“trace” amounts) or too large (e.g. very large Big Skate). The unique trip identifier and set number are included so that catches can be related to the fishing event information (including capture location).Biology:This table contains Eulachon biological data including length, sex, and weight. Information is provided on whether stomachs or teeth were examined, and whether genetics (DNA) samples were collected. Eulachon maturity data, diet data, and teeth presence data are available on request from the data contacts. Additional analyses are ongoing, including histology, fatty acid profiling, and genetic analysis; frozen heads are also available for a future aging project. In addition to the Eulachon biological data, lengths and weights were collected from American Shad.The unique trip identifier and set number are included so that samples can be related to the fishing event and catch information.
Eulachon Migration Study Bottom Trawl Surveys - South
Catch, effort, location (latitude and longitude), and associated biological data from the Eulachon Migration Study Bottom Trawl surveys - South on the coast of British Columbia.Introduction:The Eulachon Migration Study Bottom Trawl survey - South (Eul-S) is part of the in the Eulachon Migration Study Bottom Trawl survey series and took place on the coast of British Columbia. The other survey in this series is the Eulachon Migration Study Bottom Trawl survey – North (Eul-N).The Eulachon Migration Study Bottom Trawl survey - South (Eul-S) was conducted monthly from October 2017 to March 2018 with an additional trip in January 2019 and was funded by the Fisheries and Oceans Canada (DFO) National Rotational Survey Fund.The objective of this survey was learn about the distribution, ecology, and migration times of Eulachon into the Fraser River by observing their spatial and temporal occurrence and biological condition over a wide survey region and over several months. This survey follows a random block design in a targeted depth range between 80 – 200 metres. The sampling units are 2 km by 2 km blocks. Fishing was conducted using the Canadian Coast Guard Research Vessel Neocaligus to tow an American shrimp trawl net (Cantrawl Nets Ltd., Richmond, BC). The horizontal opening of the polypropylene net was estimated to be 34 to 37 feet (10 to 11 m), while the center of the opening had a vertical height of approximately 7 to 9 feet (2 to 3 m). A 0.4” (10 mm) liner was used in the codend. The net was configured with roller gear and 72” (1.8 m) Thyboron Type 2 trawl doors. Tow duration was typically 20 minutes. The standard hours of fishing were 0700 to 1700 hours, depending on sunrise and sunset in winter months.The Eulachon Migration Study Bottom Trawl survey – South was conducted by the Department of Fisheries and Oceans Canada (DFO). The area the survey covered included the Strait of Georgia, Juan de Fuca Strait, and Haro Strait in Pacific Fishery Management areas (PFMA’s) 17-20, 28, 29, and 121.Effort:This table contains information about the survey trips and fishing events (trawl tows/sets) that are part of this survey series. Trip-level information includes the year the survey took place, a unique trip identifier, the vessel that conducted the survey, and the trip start and end dates (the dates the vessel was away from the dock conducting the survey). Set-level information includes the date, time, location, and depth that fishing took place, as well as information that can be used to calculate fishing effort (duration) and swept area. All successful fishing events are included, regardless of what was caught.Catch:This table contains the catch information from successful fishing events. Catches are identified to species or to the lowest taxonomic level possible. Most catches are weighed, but some are too small (“trace” amounts) or too large (e.g. very large Big Skate). The unique trip identifier and set number are included so that catches can be related to the fishing event information (including capture location).Biology:This table contains Eulachon biological data including length, sex, and weight. Information is provided on whether stomachs or teeth were examined, and whether genetics (DNA) samples were collected. Eulachon maturity data, diet data, and teeth presence data are available on request from the data contacts. Additional analyses are ongoing, including histology, fatty acid profiling, and genetic analysis; frozen heads are also available for a future aging project. In addition to the Eulachon biological data, lengths and weights were collected from American Shad. The unique trip identifier and set number are included so that samples can be related to the fishing event and catch information.
Fish and large decapods in eelgrass (Zostera marina) beds on the Atlantic coast of Nova Scotia, Canada
Nekton assemblages in Zostera marina beds and adjacent bare soft-sediments were sampled on the south and eastern shore of Nova Scotia. Sampling gear used were visual snorkel transects and a benthic beam trawl. Fish were identified and size either measured (trawl) or estimated in situ (snorkel transects). Surveys were conducted in mid-July to Aug in summer of 2013 and 2014 across multiple sampling sites. Multiple replicate transects were conducted at each site. Raw abundances from observations were transformed into young of year (YOY) equivalent abundance, and then into density of each species calibrated to account for the sampling equipment and day/night differences.Cite this data as: Wong, M. C. Data of: Fish and large decapods in eelgrass (Zostera marina) beds on the Atlantic coast of Nova Scotia, Canada. Published: April 2020. Coastal Ecosystems Science Division, Fisheries and Oceans Canada, Dartmouth, N.S. https://open.canada.ca/data/en/dataset/dbc56f11-4a97-45e7-99f4-71966b51630c
Hecate Strait Multispecies Assemblage Bottom Trawl Survey
Catch, effort, location (latitude and longitude), and associated biological data from the Hecate Strait Multispecies Assemblage Bottom Trawl Surveys in Hecate Strait, British Columbia.Introduction The Hecate Strait Multispecies Assemblage Bottom Trawl survey series consists of twelve surveys that were conducted from 1984 to 2003 by the Pacific Biological Station, Fisheries and Oceans Canada. The main objective of this survey series was to collect detailed catch and biological data on species assemblages in order to develop an ecological basis for mixed species stock assessment in Hecate Strait. These surveys also provided abundance indices for individual species and were a source of information on recruitment. The surveys were conducted using a combination of charter vessels and two Canadian Coast Guard Research Vessels, the R/V G.B. Reed and R/V W.E. Ricker. To determine haul locations, a grid of 19 km² (10 nautical miles²) blocks were used with an attempt made to establish one trawl site within each 18 metre depth interval within each block. The 1984 survey involved one chartered and one research vessel; all other surveys were single vessel surveys. The Hecate Strait Multispecies Assemblage Bottom Trawl survey series surveyed Pacific Fishery Management areas 4, 5, and 101 to 106. A total of 1,111 number of tows were made with a Yankee 36 trawl net. This survey series is the predecessor for the present day Hecate Strait Synoptic Bottom Trawl Survey and represents one of the longest running time series of fisheries independent groundfish surveys on the west coast.For further details about the Hecate Strait Multispecies assemblage bottom trawl survey series, a list of reports can be found in the supporting documents section.EffortThis table contains information about the survey trips and fishing events (trawl tows/sets) that are part of this survey series. Trip-level information includes the year the survey took place, a unique trip identifier, the vessel that conducted the survey, and the trip start and end dates (the dates the vessel was away from the dock conducting the survey). Set-level information includes the date, time, location, and depth that fishing took place, as well as information that can be used to calculate fishing effort (duration) and swept area. All successful fishing events are included, regardless of what was caught. CatchThis table contains the catch information from successful fishing events. Catches are identified to species or to the lowest taxonomic level possible. Most catches are weighed, but some are too small (“trace” amounts) or too large (e.g. very large Big Skate). The unique trip identifier and set number are included so that catches can be related to the fishing event information (including capture location). BiologyThis table contains the available biological data for catches which were sampled. Data may include any or all of length, sex, weight, age. Different length types are measured depending on the species. Age structures are collected when possible for species where validated aging methods exist and are archived until required for an assessment; therefore, all existing structures have not been aged at this time. The unique trip identifier and set number are included so that samples can be related to the fishing event and catch information.BiomassThis table contains relative biomass indices of species that have been captured in every survey of the time series. The coefficient of variation and bootstrapped 95% confidence intervals are provided for each index. The groundfish data synopsis report (Anderson et al. 2019) provides an explanation of how the relative biomass indices are derived.
Lumpfish catch rates since 1990 in the Estuary and Gulf of St. Lawrence (NAFO divisions 3PN and 4RST)
Spatial distribution of lumpfish catch rates (number per tow) during the August DFO research survey conducted annually since 1990, to assess the state of groundfish and shrimp stocks in the northern Gulf of St. Lawrence.The area sampled by a tow is the product of the distance trawled (fishing time multiplied by vessel speed) and the wing spread (13.41 m for the Alfred Needler and 16.94 m for the Teleost). Given that this area may vary among tows, the sampling unit is standardized and defined as being a station sampled by a tow over a distance of 0.75 nautical miles (1,389 m) with a horizontal wing spread of 16.94 m. Catch variables were calculated based on the standard area, 0.02353 km².After each tow, the catch was sorted by taxa, and the number of individuals and total biomass of these taxa were noted. For taxa identified to the species level, individual biometric parameters (e.g., length, weight) and biological parameters (e.g., sex, maturity of gonads) were recorded based on a subsample. Full methods are described in Bourdages et al. (2010).Note that the increase in catch rate for the 2005-2009 period coincides with a change in gear for this survey.Bourdages, H., and Ouellet, J.-F. 2011. Geographic distribution and abundance indices of marine fish in the northern Gulf of St. Lawrence (1990–2009). Can. Tech. Rep. Fish. Aquat. Sci. 2963: vi + 171 p.Source:Gauthier, J., Grégoire, F., and Nozères, C. 2017. Assessment of Lumpfish (Cyclopterus lumpus) in the Gulf of St. Lawrence (3Pn, 4RS) in 2015. DFO Can. Sci. Advis. Sec. Res. Doc. 2017/051. v + 47 p.PurposeThe multidisciplinary survey of groundfish and shrimp in the northern Gulf of St. Lawrence has been conducted every August by Fisheries and Oceans Canada for more than two decades. Initially, its objective was to determine the abundance and geographic distribution of commercially important taxa. However, for couple of years, the objective was expanded to include all taxa caught with the shift toward the ecosystem approach.
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