PURPOSE: To provide access to detailed stomach content data and associated metadata from Atlantic Bluefin Tuna sampled in the southern Gulf of St. Lawrence from 2018 to 2023. These data support fisheries science by contributing to analyses of predator–prey dynamics, diet composition, and ecosystem understanding, as well as informing stock assessment and fisheries management activities within Fisheries and Oceans Canada. DESCRIPTION: This dataset contains metadata and stomach content information collected from Atlantic Bluefin Tuna (ABFT) caught from mid-August to late September in the commercial fishery in the southern Gulf of St. Lawrence between 2018 and 2023. Stomach samples were primarily obtained from fish harvested near the eastern end of Prince Edward Island, with additional samples collected from the Miscou/Baie‑des‑Chaleurs area in 2018 and 2019. SAMPLING METHODS: Fish were measured to the nearest curved fork length (cm) and weighed to the nearest round weight (kg). Stomachs were obtained directly from harvesters or through a fish buyer and were stored at −20 ◦C before being processed in the laboratory. Stomachs identification numbers were cross-referenced with ABFT tag numbers recorded by fish provider in order to obtain logbook and port data (catch location, time, weight length, sex, gear, etc.) for each sample. Stomachs were thawed in the laboratory and the content was sorted and identified to the lowest possible taxonomic level. For each stomach, prey were weighed collectively as a taxonomic group and individually to the nearest 0.1 g. Dead bait used to capture ABFT, identified by cut marks, were recorded and weighed but excluded from the analysis. Live bait items cannot be identified from stomach content analyses. Only a few otoliths were found in 2018 and their degraded quality precluded performing ageing or species identification. Rare and small prey items such as algae and rocks were classified in the category “other”. Fish remains that could not be identified were classified in the category “Unidentified teleostei remains”. For 2019 to 2023, when stomach content items could not be visually identified and when tissue was available, tissue samples were collected and stored at −20 °C for DNA barcoding analysis. DNA extraction, mitochondrial cytochrome oxidase subunit 1 amplification, Sanger sequencing and species assignation were performed at the Plateforme d’Analyses Génomiques and Plateforme Bio-informatique of the Institut de Biologie Intégrative et des Systèmes (PAG-IBIS, Université Laval, Quebec city, QC, Canada, http://www.ibis.ulaval.ca/en/services-2/genomic-analysis-platform/). DNA was extracted from 20 mg of muscle tissue using the Omega Bio-tek E-Z-96 Tissue DNA Kit (Omega Bio-tek, Norcross GA, USA) following manufacturer instructions. The mitochondrial cytochrome oxidase subunit 1 region was amplified and sequenced as described in Hashemzadeh Segherloo et al., 2021). Sanger forward and reverse reads were analyzed independently using the Basic Local Alignment Search Tool against non-redundant sequences to identify the top hit for each sequence. When samples could not be identified by a top hit sequence they were classified as “unidentifiable fish”. Prey items that were successfully identified using DNA barcoding were incorporated into the stomach content analysis database and used in all subsequent diet analyses (abundance, occurrence and weight). The weight of the items used in the database was the weight of the remains as they were, and not reconstructed weights calculated for a live animal of the species identified by the barcoding. USE LIMITATION: To ensure scientific integrity and appropriate use of the data, we would encourage you to contact the data custodian.

PURPOSE: Monitor commercial landings of NAFO Division 4T Atlantic herring. DESCRIPTION: This dataset contains Atlantic herring landings (in metric tonnes) by year, spawning stock (spring and fall spawners), fishing season (spring and fall), and gear type (fixed and mobile). Stock identification (spring or fall spawners) is determined through port sampling. Two fish samples are collected per week in each herring fishing area for this purpose. Daily landings data are obtained from the DFO Statistics Branch. 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 (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. Data collected in shelf and slope waters at depths less than 400 meters off Washington and Oregon State are part of this larger survey series, but are limited to 1999-2001. These surveys focused on determining the migratory patterns of juvenile Pacific Salmon and had funding support from the Bonneville Power Administration as part of the 1995-2011 Canada-USA Salmon Shelf Survival Study. The intent of that study was to monitor and evaluate the effects of ocean conditions on the distribution, migration, growth, and survival of Pacific salmon during their first ocean year, and estimate the subsequent impacts on abundance of Chinook salmon adults returning to the Columbia River system.

Summary The Quebec region of the Department of Fisheries and Oceans (DFO) is responsible for the assessment of several fish and invertebrate stocks exploited in the Estuary and the northern Gulf of St. Lawrence. The commercial catches sampling program is one of the sources of information used to complete these assessments. The data collected by this program, at wharf or at sea, offers among other things the advantage of a relatively large spatio-temporal coverage and provides some of the necessary knowledge to assess the demography and the structure of the exploited populations. This program is implemented by specialized DFO staff whose main mandate is to collect biological data on groundfish, pelagic fish and marine invertebrate species that are commercially exploited in the various marine communities. Data This dataset on the Atlantic mackerel (Scomber scombrus) includes the metadata, sample weight, fish length, the sex and the number of specimens measured. This dataset covers the periods of 1976-1977 and 1984 to present. In order to protect the confidentiality of the sources, some informations (such as those concerning the vessel) have been excluded and others (such as the date of capture) have been simplified. Entries where there was only one vessel in a fishing area for a given year were also excluded. Further information including the fishing areas coordinates can be found by clicking on the «Atlantic and Arctic commercial fisheries» and «Fishing areas» links below.

Fisheries and Oceans Canada (DFO) conducted a winter multidisciplinary scientific surveys with a bottom trawl the northern Gulf of St. Lawrence and Cabot Straight from 1978 to 1994. The specificities of the missions onboard the MV Lady Hammond are described below. Objectives: 1. Assess groundfish populations abundance and condition 2. Assess environmental conditions 3. Conduct a biodiversity inventory of benthic and demersal megafauna 4. Collect samples for various research projects Survey description This winter survey covers the northern Gulf of St. Lawrence, that is the divisions 4R, 4S and 3Pn of the Northwest Atlantic Fisheries Organization (NAFO). A stratified random sampling strategy is used for this survey and the fishing gear used on the MV Gadus Atlantica is an Engel 145 Otter trawl. Standard trawling tows last 30 minutes, starting from the time the trawl touches the sea floor. Towing speed is 3.5 knots. Data For each fishing tow, the catch is sorted and weighed by taxa; individuals are 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 otoliths are collected for Greenland halibut and Atlantic cod. Invertebrates are weighted and counted (no individual measurements). The biological data are divided into 4 files: a “Metadata” file containing set information, a “Catches” file containing catches per set for fish taxa, a “Carbio” file containing morphometric measurements per individual and a “Freql” file containing the length frequency of fish. 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).

Water level and discharge data are available from Water Survey of Canada’s Hydrometric Network. The Water Survey of Canada (WSC) is the national authority responsible for the collection, interpretation and dissemination of standardized water resource data and information in Canada. In partnership with the provinces, territories and other agencies, WSC operates over 2500 active hydrometric gauges across the country, maintains an archive of historical information for over 7600 stations and provides access to near real-time (water level and stream flow) provisional data at over 1700 locations in Canada.

Summary The Quebec region of the Department of Fisheries and Oceans (DFO) is responsible for the assessment of several fish and invertebrate stocks exploited in the Estuary and the northern Gulf of St. Lawrence. The commercial catches sampling program is one of the sources of information used to complete these assessments. The data collected by this program, at wharf or at sea, offers among other things the advantage of a relatively large spatio-temporal coverage and provides some of the necessary knowledge to assess the demography and the structure of the exploited populations. This program is implemented by specialized DFO staff whose main mandate is to collect biological data on groundfish, pelagic fish and marine invertebrate species that are commercially exploited in the various marine communities. Data This dataset on the snow crab (Chionoecetes opilio) includes the metadata, sample weight, specimen weight, shell width and condition, sex and the right claw height of the specimens measured. This dataset covers the periods of 1984-2003 and 2005 to present. In order to protect the confidentiality of the sources, some informations (such as those concerning the vessel) have been excluded and others (such as the date of capture) have been simplified. Entries where there was only one vessel in a fishing area for a given year were also excluded. Further information including the fishing areas coordinates can be found by clicking on the «Atlantic and Arctic commercial fisheries» and «Fishing areas» links below.

Mean fork length for returning adult Atlantic salmon (Salmo salar) that spent one or two years (1SW and 2SW, respectively) in the marine environment for 16 rivers throughout Eastern Canada spanning an 10° latitudinal gradient. These data were collected as part of monitoring programs for Atlantic salmon returns run by Fisheries and Oceans Canada (DFO). Data from at least eight populations, spanning all provinces in Atlantic Canada, over a 50-year period (1970-2021) will be included in this meta-analysis. These data, as well as mean fork length for returning adult Atlantic salmon from three rivers in Québec (1979-2021) collected as part of monitoring programs for Atlantic salmon returns run by the Ministère de l’Environnement, de la Lutte contre les changements climatiques, de la Faune et des Parcs, Government of Québec, are also available at: http://doi.org/10.17605/OSF.IO/78PWT.

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.

This record contains data on beluga whale locations in the Mackenzie estuary reported in Harwood, L.A. and P. Norton (1996). Aerial survey data from the southeast Beaufort Sea, Mackenzie River estuary and west. Amundsen Gulf, July 1992. Canadian Data Report of Fisheries and Aquatic Sciences No. 964