Polar cod (Boreogadus saida), Atlantic cod (Gadus morhua), and Greenland cod (Gadus macrocephalus) are prominent gadid species within the northwest Atlantic Ocean in terms of their ecological and socio-economic importance but it is unclear how climate-induced changes in ocean temperature may alter their distributions by the end of the century (2100). We used physiologically based species distribution models to predict how ocean warming will influence the availability of suitable habitat for early life-stages in these marine gadids. We applied CMIP5 ocean temperature projections to egg survival and juvenile growth models for Polar cod, Atlantic cod, and Greenland cod to create predicted suitability raster surfaces for these metrics across four climatology periods (1981–2005, 2026–2050, 2051–2075, 2076–2100). The analysis focused on the projected changes in temperature in ocean shelf areas where ocean depth is ≤400 m. We created an integrated habitat suitability index by combining the suitability surfaces for egg survival and growth potential to predict areas and periods where thermal conditions were suitable for both life stages. The resulting surfaces indicate that suitable thermal habitat for the juvenile life stages of all three species will shift poleward, but the magnitude of the shift and the overall area of thermally suitable habitat remaining will differ across species and life stages through time. Modelled layers are provided in NetCDF format by metric (egg survival, growth potential, habitat suitability). Data layers for Polar cod, Atlantic cod, and Greenland cod are included within each NetCDF file as variables across time. Note that in this study we refer to Gadus macrocephalus/ogac as Greenland cod since Gadus ogac is thought to be a junior synonym of Gadus macrocephalus (Carr et al., 1999). For more details on the methods and results for this analysis see Cote et al. (2021).References:Carr, S. M., Kivlichan, D. S., Pepin, P., & Crutcher, D. C. (1999). Molecular systematics of gadid fishes: implications for the biogeographic origins of Pacific species. Canadian Journal of Zoology, 77(1), 19–26. https://doi.org/10.1139/cjz-77-1-19Cote, D., Konecny, C. A., Seiden, J., Hauser, T., Kristiansen, T., & Laurel, B. J. (2021). Forecasted Shifts in Thermal Habitat for Cod Species in the Northwest Atlantic and Eastern Canadian Arctic. Frontiers in Marine Science, 8(November), 1–15. https://doi.org/10.3389/fmars.2021.764072

The Department of Fisheries established a survey of demersal juvenile Atlantic cod (*Gadus morhua*) in the nearshore (<10 m deep) in 1959. This survey aimed to characterize the distribution and abundance of juvenile Atlantic cod and was based upon Norway's Flodevigen sampling program which has been conducted continuously since 1919. A 25 m seine was used to sample juvenile Atlantic cod nursery locations on the Avalon Peninsula and Northeast coast of the island of Newfoundland in September and October. The survey continued until 1964 and became known as the Fleming survey, after original initiator Alistair Fleming. The survey was reinstated by Memorial University of Newfoundland from 1992 to 1997. Multiple tows were conducted at a subset of the original 55 Fleming sites located in St. Mary's Bay, Trepassey Bay, the Southern Shore, Conception Bay, Trinity Bay, Bonavista Bay, Gander Bay, New World Island, Fortune Harbour, Badger Bay, Halls Bay and Green Bay.This data set includes several different subsets, some of which span both Fleming Survey periods (1959-1964 and 1992-1997):I. JuvCodCatch60s90s:Catches of juvenile Atlantic cod (1959-1964, 1992-1997) from the first two consecutive tows at each site. This is a summary based on JuvCodLengths90s and FlemingSurveyData60s;II. JuvCodLength90s:Lengths of all individual juvenile Atlantic cod caught for each site (1992-1997);III. SiteEnvData60s90s:Station data for Fleming data 1992-1997;IV. FlemingSurveyData60s:Fleming survey data from 1959-1964 (note there are three record types pertaining to: station data "type 1"; general species catch data including juvenile Atlantic cod grouped by age class ("1+", "Zeroes", and "Total") "type 2; and juvenile Atlantic cod (species 223) listed in length bins "type 3"; andV. FlemingBycatch60s92to96:Bycatch data from 1959-1964 & 1992-1996 from first two tows at each site. This is a summary based partly on the FlemingSurveyData60s set.

SummaryThe 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.DataThis dataset on the Atlantic cod (Gadus morhua) includes the metadata, sample weight, fish length, the sex and the number of specimens measured. This dataset covers the period of 1983 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.

This project was completed by the Groundfish Section in the Newfoundland and Labrador Science Branch of Fisheries and Oceans Canada (DFO). From 2018 to 2020, 14 year-round, acoustic receivers were deployed in Placentia Bay as a part of the Coastal Environmental Baseline Program to form 4 gates: Bar Haven (2 receivers), Centre Channel (1 receiver), Eastern Channel (6 receivers), and Western Channel (5 receivers). Additionally, 162 transmitters were deployed in Atlantic cod in the 3Ps region (2019-2022). Over the deployment period these receivers recorded a total of 2 094 024 detections from 63 unique transmitters including 45 Cod tagged through the Groundfish acoustic telemetry program. Most cod detected were tagged in Placentia Bay (43 fish) and many were detected at multiple receivers or multiple years (37 fish). Passive data collection for this project may extend up to 2030. This record contains the locations of the acoustic receivers in Placentia Bay, NL.

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 condition2. Assess environmental conditions3. Conduct a biodiversity inventory of benthic and demersal megafauna4. Collect samples for various research projectsSurvey descriptionThis 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.DataFor 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).

2014 to 2023 demersal fish abundance in the Estuary and the Gulf of St. Lawrence. The abundance is expressed as a number of individuals per normalized trawl set. Each species is individually represented in the northern Gulf and in the southern Gulf. Input data are from the annual August (North) and September (South) multidisciplinary surveys.The demersal species represented are: Alewife, Alligatorfish, American Plaice, Arctic Alligatorfish, Arctic Hookear Sculpin, Arctic Shanny, Arctic Staghorn Sculpin, Atlantic Cod, Atlantic Eelpout, Atlantic Halibut, Atlantic Hookear Sculpin, Atlantic Poacher, Atlantic Spiny Lumpsucker, Atlantic Wolffish, Black Dogfish, Blacksnout Seasnail, Brill/Windowpane, Common Grenadier, Common Wolf Eel, Cunner, Daubed Shanny, Esmark's Eelpout, Fish Doctor, Fourbeard Rockling, Fourline Snakeblenny, Greenland Cod, Greenland Halibut, Haddock, Longfin Hake, Longhorn Sculpin, Lowfin Snailfish, Monkfish, Goosefish, Moustache Sculpin, Newfoundland Eelpout, Northern Hagfish, Ocean Pout, Rockfishes, Sea Sculpin, Sea Tadpole, Shorthorn Sculpin, Smooth Skate, Snakeblenny, Spatulate Sculpin, Spiny Dogfish, Spinytail Skate, Spotted Wolffish, Stout Eelblenny, Thorny Skate, Twohorn Sculpin, Vahl's Eelpout, Variegated Snailfish, White Hake, Winter Flounder, Winter Skate, Witch Flounder, Wolf Eelpout, Wrymouth and Yellowtail Flounder.PurposeSince 1990, the Department of Fisheries and Oceans has been conducting an annual multidisciplinary survey in the Estuary and northern Gulf of St. Lawrence using a standardized protocol. In the southern Gulf of St. Lawrence, these bottom trawl surveys has been carrying out each September since 1971. These missions are an important source of information about the status of the marine ressources.The objectives of the surveys are multiple: to estimate the abundance and biomass of groundfish and invertebrates, to identify the spatial distribution and biological characteristics of these species, to monitor the biodiversity of the Estuary and Gulf and finally, to describe the environmental conditions observed in the area at the moment of the sampling.The southern Gulf surveys are realized using the following standardized protocol:Hurlbut,T. and D.Clay (eds) 1990. Protocols for Research Vessel Cruises within the Gulf Region (Demersal Fish) (1970-1987). Can. MS Rep. Fish. Aquat. Sci. No. 2082: 143p.The sampling protocols used for the Estuary and northern Gulf surveys are described in details in the following publications:Bourdages, H., Archambault, D., Bernier, B., Fréchet, A., Gauthier, J., Grégoire, F., Lambert, J., et Savard, L. 2010. Résultats préliminaires du relevé multidisciplinaire de poissons de fond et de crevette d’août 2009 dans le nord du golfe du Saint-Laurent. Rapp. stat. can. sci. halieut. aquat. 1226 : xii+ 72 p. Bourdages, H., Archambault, D., Morin, B., Fréchet, A., Savard, L., Grégoire, F., et Bérubé, M. 2003. Résultats préliminaires du relevé multidisciplinaire de poissons de fond et de crevette d’août 2003 dans le nord du golfe du Saint-Laurent. Secr. can. consult. sci. du MPO. Doc. rech. 2003/078. vi + 68 p.Annual reports are available at the Canadian Science Advisory Secretariat (CSAS), (http://www.dfo-mpo.gc.ca/csas-sccs/index-eng.htm).Bourdages, H., Brassard, C., Desgagnés, M., Galbraith, P., Gauthier, J., Légaré, B., Nozères, C. and Parent, E. 2017. Preliminary results from the groundfish and shrimp multidisciplinary survey in August 2016 in the Estuary and northern Gulf of St. Lawrence. DFO Can. Sci. Advis. Sec. Res. Doc. 2017/002. v + 87 p.

In place since fall 1994, the sentinel fisheries program is the result of a collaboration between Fisheries and Oceans Canada (DFO) and Quebec and Newfoundland commercial fishermen's associations. Under this program, contracts are awarded by tender to fishermen’s associations to carry out fishing activities according to scientific protocols developed by DFO. The main objective of this survey is to collect data that will be used to calculate abundance indices for the northern Gulf of St. Lawrence Atlantic cod stock.Description of fixed gears surveyThe fixed gear sentinel fisheries of the northern Gulf of St. Lawrence are conducted in the sub-division 3Pn and the divisions 4R, 4S of the Northwest Atlantic Fisheries Organization (NAFO) using fixed gillnets or longlines (other fishing gears were also used at the start of the program). Fishing activities with nets must have a mesh size of 5 ½ inches (140mm) and are limited to a maximum of 6 to 20 nets depending on the region and capture and the target immersion time is between 19 to 24 hours. Longline fishing activities, for its part, must be carried out with traditional J #16 or C #12 hooks. The maximum number of hooks varies from 500 to 1000, depending on the catch, and the target immersion time is 4 to 6 hours. Data are collected by observers at sea or by technicians.DataFor each fishing activity, the total catch is sorted and weighed by species. For each species other than Atlantic cod, the number of individuals caught is noted. Atlantic cod are then measured at the fork (cm). Other biological data such as weight (total, gonad, liver and stomach), age, sex and maturity can then be collected on a subsample of cod.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 biological and morphometric measurements per individual, a “Freql” file containing the length frequency of fish.The data collected as part of this program is available below. It is important to note, however, that 1) only traits deemed successful have been retained; 2) historical data may contain inaccuracies; 3) the most recent survey is not available for validation purposes.

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.The following species have been sampled by this program from 1976 to present:1. American lobster (Homarus americanus)2. American plaice (Hippoglossoides platessoides)3. Atlantic cod (Gadus morhua)4. Atlantic halibut (Hippoglossus hippoglossus)5. Atlantic herring (Clupea harengus)6. Atlantic lyre crab (Hyas araneus)7. Atlantic mackerel (Scomber scombrus)8. Atlantic surfclam (Spisula solidissima)9. Arctic Lyre Crab (Hyas coarctatus)10. Capelin (Mallotus villosus)11. Common softshell clam (Mya arenaria)12. Giant scallop (Placopecten magellanicus)13. Greenland halibut (Reinhardtius hippoglossoides)14. Green urchin (Strongylocentrotus droebachiensis)15. Iceland scallop (Chlamys islandica)16. Redfish (Sebastes sp.)17. Rock crab (Cancer irroratus)18. Sea cucumber (Cucumaria frondosa)19. Snow crab (Chionoecetes opilio)20. Stimpson surfclam (Mactromeris polynyma)21. Waved whelk (Buccinum undatum)22. White hake (Urophycis tenuis)23. Winter flounder (Pseudopleuronectes americanus)24. Yellowtail flounder (Limanda ferruginea)For more information concerning these species, see the «Related Products» section below.

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.

This project was completed by the Coastal Environmental Baseline Program (Coastal and Freshwater Ecology Section) in the Newfoundland and Labrador Science Branch of Fisheries and Oceans Canada (DFO). The nearshore fish and invertebrate community was sampled annually in Placentia Bay at 14 sites for 5 years (2018 – 2022). The objective of this program was to collect data on juvenile fish (specifically Atlantic cod) communities and habitats within Placentia Bay. The sites and timing (October) were selected based on historical sampling. There were several data types collected during each of these sampling trips. Boat-based beach seining was used to collect data on fish and invertebrate diversity, abundance, distribution, and size. Visual transects were used to identify vegetation and substrate (habitat) types and proportions at seine sites. CTD profiles (temperature, conductivity, depth, and salinity) were obtained using a castaway CTD. Finally, eDNA samples were collected at each site (2018-2021) to obtain complementary information on the presence of juvenile fish and other species present. This record contains the geographic locations of the 14 sites, and information on the timing and type of data collected at each site.