Since 1992, scientific surveys have been conducted annually alternately, in the estuary and the North of the Gulf of Saint Lawrence. These surveys allow DFO to monitor the population and ecosystem of the snow crab and thus understand the state of the stock and the renewal of the species.Beam trawl hauls following a systematic sampling take place every 2 years in the estuary and in the Lower North Shore. In the estuary (zone 17), a sampling of 94 stations is carried out. In the Lower North Shore (zone 13 and 14), 60 regular stations are usually sampled and 35 exploratory stations are distributed between Baie Johan Bettz and Kegaska (zone 15 and 16) but also on the south shore of zone 13 near Newfoundland. At each station, a fishing haul of 5 to 10 minutes is carried out. The harvested crabs are measured (cephalothorax width), sexed and counted. The state of the shell, sexual maturity and egg development stages are also assessed. The number of crabs caught, classified according to different size categories, allows estimating densities and thus monitoring the state and renewal of the snow crab population in the different fishing areas. This dataset on the snow crab (Chionoecetes opilio) contains abundance and density data of crabs under different size classes as well as geographical and bathymetric variables by station. The dataset covers the period from 1992 to the present and is updated each year. A cleaning of aberrant data has been carried out.For certain time periods, associated species are identified and semi-quantitatively counted directly on the sorting table, and the results are presented in the following publications: - https://open.canada.ca/data/en/dataset/8fbd81a4-ce4a-40e3-81f6-e2a5c44955de- https://open.canada.ca/data/en/dataset/268bf29e-b9d6-4267-bc86-230f4edfb80b- https://open.canada.ca/data/en/dataset/97dac757-2ef6-4144-b7d9-a0d8d51f8319

A research survey on American lobster (Homarus americanus) and rock crab (Cancer irroratus) has been carried out annually on the Magdalen Islands since 1995 to assess the abundance and structure of populations in this area. The survey is carried out during the first two weeks of September and covers the southern part of the Magdalen Islands, from "Baie de Plaisance" to "Grande-Entrée", extending slightly eastwards between "Havre-aux-Maisons" and "Grande-Entrée". The survey lasts 8 to 15 days, depending of the weather conditions, and covers a maximum of 48 stations. Approximately half of the stations are surveyed in duplicate (two tows per station). The tows always cover 500 meters, with a slightly variable trawl opening (as explained above), averaging around 10 meters.The gear used is a Nephrops trawl, a benthic trawl originally developed for langoustine fishing in Brittany, but slightly modified to target lobster. The trawl is deployed from the CCGS Leim and the harvested organisms are hauled aboard and sorted. Cephalothorax length, sex and shell stage are recorded for all lobsters. This is supplemented by information on reproductive conditions for certain size classes, and dissections of 25 males and 25 females per mission. Rock crabs are also included in the survey and are counted with additional measurements of shell width, sex and shell condition that are recorded on predetermined stations. For other stations individuals data are collected depending on the time available between trawl hauls.The publication contains 4 files; the "Information_stations" file which contains the data of the stations, the "Data_homard_lobster_survey" file which contains the measurements of each lobster, the "Nombre_crabe_crab_number" file which contains the count of rock crabs, the "Mesure_crabe_crab_measurement" file contains the characteristics measured for each crab. Each of the files can be linked by the "date", "st", "tr" columns. The “bat” column notes the boat code, because the gear is not deployed in the same way on each boat.*This record consist of raw data and quality has not been verifiedAssociated species are identified and semi-quantitatively counted directly on the sorting table, and the results are presented in the following publication: https://open.canada.ca/data/en/dataset/99cb7034-f3d5-4da4-a5bc-e81315cfb8eb

This data report provides information on temperature and salinity in the Godbout region of the St. Lawrence Estuary. Sampling was carried out from 2019 to 2021 over an area of <5 km2. The databases provide information on temperature and salinity at an hourly rate for 2 years. The aim of this project is to analyze telemetry data from sea urchins (Strongylocentrotus droebachiensis), snow crabs (Chionoecetes opilio), rock crabs (Cancer irroratus), spider crabs (Hyas spp.) and whelks (Buccinum undatum). This report focuses on the presentation of benthic environmental data collected throughout the study with high spatial and temporal resolution. All reported variables were collected at the seafloor, as the aim of the project was to study the movement of epibenthic species. Temperature data were collected from three devices: telemetry receivers with integrated temperature sensors (InnovaseaTM), HoboTM and Star-OddiTM probes. Temperature data processing involved cleaning up extreme values (below 2°C and above 20°C) and homogenizing the data to fit the bathymetry matrix (1m x 1m cells) of the study site. Temperature data are provided in a NetCDF file with a matrix of the entire study site, where there is a stratum for each hour between August 2019 and October 2021 and in each file, a temperature value for each pixel of the raster. Salinity data were collected from Star-OddiTM probes only. Salinity values were averaged hourly for the entire study area. Salinity data is provided as a CSV file with one salinity value per hour for the entire study area.

PURPOSE:Provide presence/absence and abundance data for the non-indigenous and invasive European green crab (EGC) in selected southern Gulf of St. Lawrence (sGSL) estuaries along the Northumberland Strait coast of New-Brunswick and eastern Prince-Edward-Island.DESCRIPTION:Temporal monitoring during ice-free seasons of European green crab abundance is completed in response to previous regional population declines in the Maritime provinces. Note that where presence is not indicated on the map does not mean absence - this survey is limited to a few sites.Traps that did not fish correctly were not included in the dataset. Examples of defective traps include: an open trap, an open bait container, a trap filled with algae and falling into the open position, a trap that has not been fished for over 48 hours, an overturned trap, or a trap that has been significantly moved or otherwise tampered with.Population estimates are not derived from this data. PARAMETERS COLLECTED:1) EGC count, size measurement, sex, and catch weight2) Counts of bycatch species. Categories reported in this dataset are finfish (cunner, striped bass, mummichog, winter flounder, smooth flounder, sculpin, tomcod, American eel, banded killifish, flounder, unknown bony fish), Atlantic rock crab, American lobster, and other (lion's mane jellyfish, moon jellyfish, other crabs, moon snail). Other smaller species were often in the trap but were not included as bycatch in this dataset as they can easily escape the mesh size and would not consistently be trapped. 3) Environmental data: water depth at trap setting, sediment type, vegetation types noted, salinity, water temperature, dissolved oxygen (not included), specific conductance (not included), conductivity (not included), weather, cloud cover (not included), tide state and direction (upon fishing).NOTES ON QUALITY CONTROL:Data entry of morphological parameters randomly verified for accuracy.Weights are not reported for PEI sites due to inconsistencies with types of weighing scales and measurement protocols.PHYSICAL SAMPLE DETAILS:Whole European green crab specimensSAMPLING METHODS:Baited trapping with Fukui traps. Bait was in a bait can or bag. Types of bait included herring (predominant type used), as well as other species when herring were not available (gaspereau, canned fish [tuna, kippers, snack sardines], mackerel, tilapia, and perch).USE LIMITATION:To ensure scientific integrity and appropriate use of the data, we would encourage you to contact the data custodian.

Fisheries and Oceans Canada’s (DFO) National Biofouling Monitoring Program (BMP) has conducted annual field surveys to monitor the introduction, establishment, spread, species richness, and relative abundance of native and non-indigenous species (NIS) since 2006. Standardized monitoring protocols employed by DFO-Maritimes, -Gulf, and -Quebec Regions include biofouling collector plates deployed from May to October at intertidal and shallow subtidal, geo-referenced sites, including public and private docks, aquaculture lease sites, public and private marinas and yacht clubs. Initially in the Maritimes Region (2006-2017) collectors consisted of 3, 10 cm by 10cm PVC plates deployed in a vertical array and spaced approximately 40-cm apart with the shallowest plate hung at least 1 m below the surface to sample shallow subtidal and intertidal species (Sephton et al. 2011, 2017). Two replicate arrays were deployed at least 5 m apart per site. Since 2018, collector arrays were modified to enhance statistical replication, including 10 individual collectors deployed per site at 1 m depth and at least 5 m apart (as above) from May to October. The percent cover of AIS on all collectors was determined by visual examination and scored as follows; (i) ‘0’ = absent, (ii) ‘1’ = ≤25 % cover, (iii) ‘2’ = 25 to ≤50 %, (iv) ‘3’ = 50–75% , and (v) ‘4’ = >75%. Average percent cover is provided for all NIS observed annually per site. Presence-absence indicates that an NIS was observed on at least one collector plate. One additional rocky intertidal species (Asian shore crab; Hemigrapsus sanguineus) was assessed via beach surveys as permitted by time and resources following its initial siting in St Mary’s Bay (Nova Scotia) in April 2020. Rapid assessment surveys conducted in the Fall of 2020 and 2021 were employed to delineate H. sanguineus’ distribution and relative abundance. Areas deemed suitable and at high risk for spread were targeted, including exposed rocky intertidal habitat in southwest regions of Nova Scotia and New Brunswick. Each rapid assessment consisted of 30-minute beach surveys per site conducted by 2 or 3 people (modified from Stephenson et al. 2011). During each survey, crabs were collected under rocks and seaweed in preferred cobble/boulder habitat (Lohrer et al. 2000). Count data was standardized for each site as the number of crabs collected per 30-min search per person.Cite as:DFO-Maritimes Biofouling Monitoring Program. Published October 2018, Updated December 2023. Coastal Ecosystems Science Division, Fisheries and Oceans Canada, Dartmouth, NSCitations:Sephton D, B Vercaemer, JM Nicolas, J Keays (2011) Monitoring for invasive tunicates in Nova Scotia, Canada (2006-2009) Aquatic Invasions 6: 391-403.Sephton D, B Vercaemer, A Silva, L Stiles, M Harris, K Godin (2017) Biofouling monitoring for aquatic invasive species (AIS) in DFO Maritimes Regions (Atlantic shore of Nova Scotia and southwest New Brunswick): May-November, 2012-2015. Canadian Technical Report of Fisheries and Aquatic Sciences 3158: 72 pp.Stephenson EH, RS Steneck, RH Seeley (2009) Possible temperature limits to range expansion of non-native Asian shore crabs in Maine. Journal of Experimental Marine Biology and Ecology 375: 21–31. doi:10.1016/j.jembe.2009.04.020

These data sets provide information pertaining to epifauna taxa including bottom-dwelling shrimp and fish along trawling transects in Bones Bay and Turnour Bay between 2001 and 2002. Data sets were compiled and formatted by Meagan Mak.Abstract from the report:This study is a component of a larger project designed to assess potential effects of shrimp trawling gear on epifauna, shrimp, fish, and benthic habitat of Clio Channel located in Broughton Archipelago, British Columbia, Canada. Replicate beam-trawl surveys were carried out on individual transects in both Bones Bay and Turnour Bay located in the northern and southern portions of Clio Channel, respectively. A submersible, towed video-camera surveyed the seabed to enumerate epifauna and fish taxa before and after trawling activities. In regards to the video surveys, fish and epifauna (e.g. common shrimp) were observed across Clio Channel, while sea whips were predominate in the Turnour Bay video transects.

A research survey on snow crab (Chionoecetes opilio) was conducted from May 2006 to May 2009 in the Bay of Ste. Marguerite near Sept-Îles, Quebec. The main objective of this survey was to assess the abundance of snow crab and benthic species associated with snow crab habitat. Only data for benthic species associated with snow crab habitat are presented in this dataset.Data were collected according to a fixed station sampling design consisting of 79 stations, between 7 to 198 meters depth. Specimens were collected using a beam trawl. The codend was lined with a small stretched mesh net in order to harvest the small individuals. The hauls were made at a target duration of 15 minutes. Start and end positions were recorded to calculate the distance traveled on each tow using the geosphere library in R. The two files provided (DarwinCore format) are complementary and are linked by the "eventID" key. The "Activity_Information" file includes generic activity information, including date and location. The "occurrence_taxon" file includes the taxonomy of the species observed, identified to the species or lowest possible taxonomic level. To obtain the abundance and biomass assessment, contact Bernard Sainte-Marie (Bernard.Sainte-Marie@dfo-mpo.gc.ca).For quality controls, all taxonomic names were checked against the World Register of Marine Species (WoRMS) to match recognized standards. The WoRMS match was placed in the "ScientificnameID" field of the occurrence file. Data quality checks were performed using the R obistools and worrms libraries. All sampling locations were spatially validated.

A research survey on snow crab (Chionoecetes opilio) was conducted from July 1 to July 17, 2018 on the Lower North Shore of the Gulf of St. Lawrence between Havre-Saint-Pierre and Blanc-Sablon. The main objective of this survey was to assess the abundance of snow crab and benthic species associated with snow crab habitat. Only data for benthic species associated with snow crab habitat are presented in this dataset.Data were collected according to a fixed station sampling design consisting of 61 stations, between 46 and 230 meters depth. Specimens were collected using a beam trawl with a total width of 2.8 meters and a total height of 0.76 meters. The codend was lined with a 16 millimeter stretched mesh net in order to harvest the small individuals. The hauls were made at a target speed of 2 knots and a target duration of 10 minutes depending on seabed conditions. Start and end positions were recorded to calculate the distance traveled on each tow using the geosphere library in R. The average tow distance was approximately 25 m. The area covered at each tow was the product of the trawl opening and the distance traveled.The two files provided (DarwinCore format) are complementary and are linked by the "eventID" key. The "Activity_Information" file includes generic activity information, including date and location. The "occurrence_taxon" file includes the taxonomy of the species observed, identified to the species or lowest possible taxonomic level. To obtain the abundance and biomass assessment, contact Cedric Juillet (cedric.juillet@dfo-mpo.gc.ca).For quality controls, all taxonomic names were checked against the World Register of Marine Species (WoRMS) to match recognized standards. The WoRMS match was placed in the "ScientificIDname" field of the occurrence file. Special cases were noted in the "commentsIdentification" field and selected specimens were confirmed with field photos. Data quality checks were performed using the R obistools and Worms libraries. All sampling locations were spatially validated.

This project was completed by the Shellfish Section in the Newfoundland and Labrador Science Branch of Fisheries and Oceans Canada (DFO), in collaboration with industry partners. The Coastal Environmental Baseline program supported the Placentia Bay portion of project work for an ongoing industry-DFO collaborative post-season trap survey for Snow Crab that was initiated in 2003 and has occurred each year. This survey is conducted by Snow Crab harvesters accompanied by at-sea observers and takes place in NAFO Divisions 2J3KLNOP4R. Historically the survey focused on commercial fishing grounds but began transitioning to a partly random stratified design in 2017. Since 2018, approximately 50% of survey stations are randomly allocated while 50% remain fixed. At each station, six (for inshore stations) or ten (for offshore stations) commercial traps are set in a fleet. To gather data on non-commercial sized Snow Crab, including females, many fleets also include one small-mesh trap. The coverage of small-mesh traps has been expanding in recent years with the aim of one small-mesh trap for every station in the coming years. Biological sampling is undertaken on at least one commercial trap and the small-mesh trap at each station. The data from this survey is incorporated into the annual stock assessment for Snow Crab in the Newfoundland and Labrador region. This record contains trap locations for Placentia Bay, and information on the types of data collected. More detailed information can be found in Pantin et al. (2022).https://publications.gc.ca/collections/collection_2023/mpo-dfo/fs70-5/Fs70-5-2022-076-eng.pdf

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.