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.

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.

Fisheries and Oceans Canada (DFO) conducts an annual summer multidisciplinary scientific survey with a bottom trawl in the Estuary and the northern Gulf of St. Lawrence since 1984. Over the years this survey has been conducted on four vessels: the MV Lady Hammond (1984-1990), the CCGS Alfred Needler (1990-2005), the CCGS Teleost (2004-2021) and the CCGS Cabot (2022-current). It is important to note that the objectives, the methods used and the identification of the species during these surveys have improved over time in response to DFO requests and mandates. The data are therefore not directly comparable between these surveys. The specificities of the missions onboard the CCGS Alfred Needler are described below.Objectives:1. Assess groundfish and northern shrimp population abundance and condition2. Assess environmental conditions3. Conduct a biodiversity inventory of benthic and demersal megafauna4. Monitor the pelagic ecosystem5. Collect samples for various research projectsSurvey descriptionThe survey covers the divisions 4R, 4S, 3Pn and the northern part of division 4T of the Northwest Atlantic Fisheries Organization (NAFO). This survey follows a stratified random sampling design and the fishing gear used on the CCGS Alfred Needler is a URI shrimp trawl (81'/114'). Standard trawling tows last 25 minutes, starting from the time the trawl touched the sea floor. Towing speed is 3 knots.DataFor each fishing tow, the catch is sorted and weighed by taxa; individuals are then counted and biological data are collected on a subsample. For fish, crab and squid, size and weight are measured by individual and, for some species, sex, gonad maturity, and the weight of certain organs (stomach, liver, gonads) are also evaluated. The soft rays of the anal fin are counted for redfish, and the otoliths are collected for several species such as witch flounder, Atlantic cod, Greenland halibut and Atlantic halibut. A roughly 2-kg shrimp sample is sorted and weighed by species (and by stage of maturity for northern shrimp). The shrimps are measured individually. The other invertebrates are counted (no individual measurements) and photographed.The biological data are divided into 5 files: a “Metadata” file containing set information, a “Catches” file containing catches per set for fish taxa, a “Carbio” file containing biological and morphometric measurements per individual, a “Freql” file containing the length frequency of fish and a “Shrimps” file containing information on shrimp catches.It's important to note that this is raw data. Only sets considered successful are retained. In each set, all species are kept, with a few exceptions. For more information please contact the data management team (gddaiss-dmsaisb@dfo-mpo.gc.ca).

The blue whale (Balaenopterus musculus) is a wide-ranging cetacean that can be found in all oceans, inhabiting coastal and oceanic habitats. In the North Atlantic, little is known about blue whale distribution and genetic structure, and if whether animals found in Icelandic waters, the Azores, or Northwest Africa are part of the same population as those from the Northwest Atlantic. In the Northwest Atlantic, seasonal movements of blue whales and habitat use, including the location of breeding and wintering areas, are poorly understood.The behaviour of remotely-monitored animals can be inferred from a time series of location data. This is because animals tend to demonstrate stochasticity in their movement paths as a result of spatial variation in environmental characteristics, such as topography or prey density (Curio 1976; Gardner et al. 1989; Turchin 1991; Wiens et al. 1993). Predators are expected to decrease travel speed and/or increase turning frequency and turning angle when a suitable resource, e.g., food patch, is encountered (Turchin 1991), otherwise known as area-restricted search (ARS). In contrast, animals in transit or travelling tend to move at faster and more regular speeds, with infrequent and smaller turning angles (Kareiva and Odell 1987; Turchin 1998).Based on satellite telemetry to track the seasonal movements of 24 blue whales from eastern Canada in 2002 and from 2010 to 2015, it was possible to estimate trajectories and locations where ARS behaviour of blue whales was inferred at a 4h time interval.To assess blue whale movements and behavior, a Bayesian switching statespace model (SSSM) was applied to Argos-derived telemetry data (Jonsen et al. 2005; Jonsen et al. 2013). An SSSM essentially estimates animal location at fixed time intervals, movement parameters and behavioral patterns.Two important sources of uncertainty can be measured separately: estimation error resulting from inaccurate observations (Argos location error) and process variability linked to the stochasticity of the movement process (behavior mode estimation) (Jonsen et al. 2003; Patterson et al. 2008).The points visible on land are the result of errors in the Argos geographic position calculation. They have been deliberately left unchanged to assess the performance of the model, which was able to clean up some positions, but not all.Lesage, V., Gavrilchuk, K., Andrews, R.D., and Sears, R. 2016. Wintering areas, fall movements and foraging sites of blue whales satellite-tracked in the Western North Atlantic. DFO Can. Sci. Advis. Sec. Res. Doc. 2016/078. v + 38 p.

Modeled data showing the likely distribution of humpback whales. CRIMS is a legacy dataset of BC coastal resource data that was acquired in a systematic and synoptic manner from 1979 and was intermittently updated throughout the years. Resource information was collected in nine study areas using a peer-reviewed provincial Resource Information Standards Committee consisting of DFO Fishery Officers, First Nations, and other subject matter experts. There are currently no plans to update this legacy data.