PURPOSE: These data have been updated following a Canadian Science Advice Secretariat (CSAS) Regional Science Advisory Process. Associated publications are available in the citation section below or will be posted on the Fisheries and Oceans Canada (DFO) Science Advisory Schedule as they become available. DESCRIPTION: The yearly biomass estimates of Gulf of St. Lawrence Witch Flounder were obtained using a Bayesian Schaefer Surplus Production model as part of the stock assessment to year 2021. The yearly estimates presented come from Markov Chain Monte Carlo (MCMC) simulations. The yearly median estimates are provided, along with uncertainty estimates (2.5th, 25th, 75th and 97.5th percentiles). The values are in thousands of tons of 30+ cm biomass. USE LIMITATION: To ensure scientific integrity and appropriate use of the data, we would encourage you to contact the data custodian.

PURPOSE: These data have been updated following a Canadian Science Advice Secretariat (CSAS) Regional Science Advisory Process. Associated publications are available in the citation section below or will be posted on the Fisheries and Oceans Canada (DFO) Science Advisory Schedule as they become available. Determine the stock status of southern Gulf of St. Lawrence Atlantic Cod. DESCRIPTION: The yearly spawning stock biomass estimates of southern Gulf of St. Lawrence Atlantic Cod were obtained using a Statistical Catch-at-Age model as part of the stock assessment to year 2023. The yearly estimates presented come from Markov Chain Monte Carlo (MCMC) simulations. The yearly median estimates are provided, along with uncertainty estimates (2.5th, 25th, 75th and 97.5th percentiles). The values are in thousands of tons of spawning stock biomass. USE LIMITATION: To ensure scientific integrity and appropriate use of the data, we would encourage you to contact the data custodian.

A rotary screw trap (RST; also known as a smolt wheel) is used to perform a capture-mark-recapture experiment on the main stem of the Margaree River. Smolts are captured at the wheel, a subset are tagged (max 200 individuals daily) and released upriver. Individuals not tagged are enumerated and released at the wheel. A fraction of tagged individuals are recaptured at the wheel. Trap efficiency and smolt abundance can be calculated from this data.

To better understand patterns of temporal and spatial variation of fish assemblages in offshore waters of Lake Winnipeg (Manitoba, Canada), pelagic trawl tows were conducted at lakewide monitoring stations since 2002. Trawl samples collected during spring, summer, and fall from the south basin, channel, and north basin were used to study effects of season and geographic region within the lake on species biomass estimates.

“Summer” missions occur in June, July and August and these focus on the Scotian Shelf and Bay of Fundy (i.e. 4VWX 5Yb, expanding recently to include the Laurentian Channel and Georges Bank (5Zc). Collected data includes total catch in numbers and weights by species. Length frequency data is available for most species, as are the age, sex, maturity and weight information for a subset of the individual animals. Other data such as ageing material, genetic material, and stomach contents are often also collected, but are stored elsewhere. “Summer” cruises occur in May, June, July and August and these focus on the Scotian Shelf and Bay of Fundy (i.e. 4VWX). Cite this data as: Clark, D., Emberley, J. Data of MARITIMES SUMMER RESEARCH VESSEL SURVEYS. Published January 2021. Population Ecology Division, Fisheries and Oceans Canada, Dartmouth, N.S. https://open.canada.ca/data/en/dataset/1366e1f1-e2c8-4905-89ae-e10f1be0a164

The Fisheries and Oceans Canada ecosystem surveys are conducted annually and are a source of integrated ecosystem monitoring data. These survey data are the primary data source for monitoring trends in species distribution, abundance, and biological condition within the region, and also provide data to the Atlantic Zonal Monitoring Program (AZMP) for monitoring hydrographic conditions, along with zooplankton and phytoplankton. The surveys follow a stratified random sampling design, and include sampling using a bottom otter trawl, CTD rosette and vertical plankton tows. Data from the bottom trawl catch are used to monitor the distribution and abundance of fish and invertebrates throughout the Scotian Shelf, Bay of Fundy and Georges Bank. Cite this data as: Clark, D., Emberley, J. Data of MARITIMES RESEARCH VESSEL SURVEYS. Published January 2021. Population Ecology Division, Fisheries and Oceans Canada, Dartmouth, N.S. https://open.canada.ca/data/en/dataset/8ddcaeea-b806-4958-a79f-ba9ab645f53b

"Fall" missions occur primarily in October and November, but sets from September and December are also present in the data. Collected data includes total catch in numbers and weights by species. Length frequency data is available for most species, as are the age, sex, maturity and weight information for a subset of the individual animals. Other data such as ageing material, genetic material, and stomach contents are often also collected, but are stored elsewhere. "Fall" cruises occur in September, October, November and December. Cite this data as: Clark, D., Emberley, J. Data of Maritimes Fall Research Vessel Survey. Published January 2021. Population Ecology Division, Fisheries and Oceans Canada, Dartmouth, N.S. https://open.canada.ca/data/en/dataset/5f82b379-c1e5-4a02-b825-f34fc645a529

“4VSW” missions focus on the eastern half of the Scotian Shelf, and occur primarily in March, but sets in both February, and April are also present in the data. These missions use a unique stratification scheme intended to optimize the abundance estimates of cod. Collected data includes total catch in numbers and weights by species. Length frequency data is available for most species, as are the age, sex, maturity and weight information for a subset of the individual animals. Other data such as ageing material, genetic material, and stomach contents are often also collected, but are stored elsewhere. Cite this data as: Clark, D., Emberley, J. Data of Maritimes 4VSW Research Vessel Survey. Published January 2021. Population Ecology Division, Fisheries and Oceans Canada, Dartmouth, N.S. https://open.canada.ca/data/en/dataset/a851ce30-e216-4d7d-a29c-05631eef140e

The Fisheries and Oceans Canada (DFO) ecosystem surveys consist of research vessel survey data collected to monitor the distribution and abundance of fish and invertebrates throughout the Scotian Shelf, Bay of Fundy and Georges Bank. The surveys follow a stratified random sampling design, and include sampling of fish and invertebrates using a bottom otter trawl. These survey data are the primary data source for monitoring trends in species distribution, abundance, and biological condition within the region, and also provide data to the Atlantic Zonal Monitoring Program (AZMP) for monitoring hydrographic variability. Collected data includes total catch in numbers and weights by species. Length frequency data is available for most species, as are the age, sex, maturity and weight information for a subset of the individual animals. Other data such as ageing material, genetic material, and stomach contents are often also collected, but are stored elsewhere. “Spring” cruises occur in January, February, March and April, and focus on Georges Bank (i.e. 5Z). Cite this data as: Clark, D., Emberley, J. Data of MARITIMES SPRING RESEARCH VESSEL SURVEY. Published January 2021. Population Ecology Division, Fisheries and Oceans Canada, Dartmouth, N.S. https://open.canada.ca/data/en/dataset/fecf045a-95a2-4b69-8a40-818649a62716

PURPOSE: From August 2nd to September 9th, 2013, Fisheries and Oceans Canada conducted a baseline survey of marine fishes and their habitats in the southern Canadian Beaufort Sea and Amundsen Gulf as part of the Beaufort Regional Environmental Assessment (BREA) called the Beaufort Sea Marine Fishes Project (BSMFP). Sampling was conducted from the F/V Frosti at 53 stations along 8 transects. Standardized sampling was conducted using benthic trawling nets. The BSMFP is the first research project to use a large research trawls to assess the biodiversity and abundance of offshore marine fishes in this area. In total, 48 species of fish were caught, one of which was a new occurrence in the Canadian Beaufort Sea, Lycodes lavalaei. DESCRIPTION: Basic biological data for all fish caught during the 2013 BSMFP expedition. Includes identification, weight, length (total, fork, and, standard), liver weight, gonad weight, sex and maturity level. PARAMETERS COLLECTED: family species weight total length fork length standard length liver weight gonad weight sex maturity SAMPLING METHODS: Various trawl types.