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We have found 56 datasets for the keyword "mactromeris polynyma". You can continue exploring the search results in the list below.
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56 Datasets, Page 1 of 6
Known concentration areas of the Stimpson's surfclam in the Estuary and the Gulf of St. Lawrence
Stimpson's surfclam or Arctic surfclam (Mactromeris polynyma) concentration areas in this layer are described as being known and commercially exploited historically and/or currently. The mapping of these areas is based on several sources of information: exploratory fisheries, scientific surveys and fishermen's logbooks. Commercial fishery data come from three distinct sources of information: the purchase receipt, the fishermen's logbook and commercial sampling by Fisheries and Oceans Canada (DFO). All data comes from the research document published in 2015. These concentration areas are considered among the most abundant and are used for commercial fishing (note: high densities are not found strictly in these beds).This dataset does not represent the general distribution of the species nor the extent to which fishing is allowed. The extent of shellfish beds can change over time in response to, among others, harvesting and recruitment rates. The polygons might underestimate the concentration areas because fishing and sampling occur where the target resource is known to be more abundant. However, the precision is good enough for resource protection and management needs in case of an environmental incident. This information is valid until data from a most recent research survey is published.Data sources and references :DFO. 2007. Évaluation des stocks de quahog nordique (Arctica islandica) du banc de l'île de Sable et de la baie St. Mary's, et du stock de mactre de Stimpson (Mactromeris polynyma) du Banquereau. Secr. can. de consult. sci. du MPO. Avis sci. 2007/034 (Révisé). Lambert J. et P. Goudreau. 1997. Biologie et exploitation de la mactre de Stimpson (Mactromeris polynyma) sur les côtes du Québec. Sec. can. éval. stock du MPO. Doc. rech. 1997/101. 44 p. Landry, T.E., E. Wade, E. et M. Giguère. 1992. Évaluation des gisements de mactre de Stimpson, Mactromeris polynyma, dans le golfe du Saint-Laurent: résultats préliminaires. MPO, CSCPCA Doc. rech. 1992/086. 29 p.Trottier, S. et P. Goudreau. 2015. Évaluation des stocks de mactre de Stimpson (Mactromeris polynyma) des eaux côtières du Québec en 2014. Secr. can. de consult. sci. du MPO. Doc. de rech. 2016/063. Ix + 72 p.
Commercial catches sampling program in the Estuary and Gulf of St. Lawrence – Stimpson`s surfclam (Mactromeris polynyma)
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 Stimpson`s surfclam (Mactromeris polynyma) includes the metadata, sample weight, the shell width and the number of specimens measured. This dataset covers the periods of 1992, 1994-1998 and 2000-2021. 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.
Biodiversity of the Stimpson's surfclam hydraulic dredge survey in the St. Lawrence Estuary (2017)
A research survey on Stimpson's surfclam (Mactromeris polynyma) was conducted from June 15 to June 26 2017 in the Estuary of the St. Lawrence River on the Forestville deposit (Fishing Area 1A). The primary objective of this survey was to investigate the spatial distribution of pre-commercial (< 80 mm) and commercial (≥ 80 mm) sizes of Stimpson's surfclams as well as to assess the abundance and diversity of benthic species associated with the sandy habitat of the Stimpson's surfclam. Only benthic species data associated with Stimpson's surfclam habitat are presented in this dataset.Data were collected according to a systematic sampling design consisting of 77 stations, between 7 and 45 m depth. Stations were spaced 200 m apart and dispersed along a total of 18 transects perpendicular to the bathymetry. Transects were parallel and spaced 500 m apart. Specimens were collected using a hydraulic dredge of the "New England" type with a total length of 2.29 meters and a total width of 1.68 meters, of which 1.35 meters was knife width. The dredge was lined with a 19 millimeter mesh Vexar™ to harvest small individuals. The hauls were made at a speed of 0.2-0.3 knots for a duration of 2 to 3 minutes. Start and end positions were recorded to calculate the distance traveled at each tow using the geosphere library in R. The average tow distance was approximately 25 m. The area covered at each stroke was the product of the width of the dredge blade and the distance.The three files provided (DarwinCore format) are complementary and are linked by the "eventID" key. The "event_information" file includes generic event information, including date and location. The "additional_information_event_and_occurrence" file includes sample size, sampling protocol and sampling effort, among others. The "taxon_occurrence" file includes the taxonomy of the species observed, identified to the species or lowest possible taxonomic level. For abundance and biomass estimates, contact Virginie Roy (virginie.roy@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. Special cases were noted in "identificationRemarks" and selected specimens were confirmed using field photos. Data quality checks were performed using the R obistools and worrms libraries. All sampling locations were spatially validated.
Nova Scotia Hydrographic Network
The Nova Scotia Hydrographic Network is an enhanced version of the Nova Scotia Topographic Database's Water Features theme. This dataset includes network spines for connectivity of water flow and various attribution for flow direction, priority of water flow and toponymic objects where applicable.
Scientific survey of sea scallop (Placopecten magellanicus) and Icelandic scallop (Chlamys islandica) around the Magdalen Islands (fishing area 20A)
Since 1985, research surveys targeting scallops—primarily the sea scallop (Placopecten magellanicus) and, to a lesser extent, the Icelandic scallop (Chlamys islandica)—have been conducted by Fisheries and Oceans Canada (DFO) at one- or two-year intervals around the Magdalen Islands (fishing area 20A). The main objective of this survey is to assess the status of sea scallop stocks. The study area is situated south of the Magdalen Islands, where scallop beds are typically sampled at depths ranging from approximately 25 to 35 m. Sampling stations are randomly selected from a predetermined fixed grid, with sampling conducted along transects at these randomly assigned locations within the study area. Each station is sampled using a lined Digby scallop dredge (20 mm mesh size), towed for roughly 500 m across the seabed.This publication includes three files: the file biometriePetoncle_20, which contains detailed biometric data (species, size, weights and sex) from 1998 to 2024; the file taillePetoncle_20, which provides the size of the individuals sampled from 2009 to 2024; and the file traitPetoncle_20 which contains the abundances and densities per tow from 2009 to 2024. Data on abundances and densities per tow from 1998-2008 is available upon request.This dataset is updated every one to two years as data becomes available. A cleaning of aberrant data has been carried out. However, there is missing data in various columns of the dataset – use the data with caution. If you have any questions please contact DFO.DataManagementSAISB-GestionDonneesDAISS.MPO@dfo-mpo.gc.ca or the author. 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/6529a4b0-f863-4568-ac71-1fa26cf68679- https://open.canada.ca/data/en/dataset/71732ad5-5c70-4dbf-916d-a94e1380c53b
Fish Species Caught in the Miramichi, McKiel and Nashwaak Lakes
PURPOSE:To characterize food webs of lake fish communities using stable isotopes, gut content morphology and DNA. DESCRIPTION:Data sets containing fish species caught in Miramichi Lake, McKiel Lake and Nashwaak Lake. USE LIMITATION:To ensure scientific integrity and appropriate use of the data, we would encourage you to contact the data custodian.
Sea Pen Fields in the Eastern Arctic (Alfredo Trawl Sample)
Polygons denoting concentrations of sea pens, small and large gorgonian corals and sponges on the east coast of Canada have been identified through spatial analysis of research vessel survey by-catch data following an approach used by the Northwest Atlantic Fisheries Organization (NAFO) in the Regulatory Area (NRA) on Flemish Cap and southeast Grand Banks. Kernel density analysis was used to identify high concentrations and the area occupied by successive catch weight thresholds was used to identify aggregations. These analyses were performed for each of the five biogeographic zones of eastern Canada. The largest sea pen fields were found in the Laurentian Channel as it cuts through the Gulf of St. Lawrence, while large gorgonian coral forests were found in the Eastern Arctic and on the northern Labrador continental slope. Large ball-shaped Geodia spp. sponges were located along the continental slopes north of the Grand Banks, while on the Scotian Shelf a unique population of the large barrel-shaped sponge Vazella pourtalesi was identified. The latitude and longitude marking the positions of all tows which form these and other dense aggregations are provided along with the positions of all tows which captured black coral, a non-aggregating taxon which is long-lived and vulnerable to fishing pressures.These polygons identify sea pen fields from the broader distribution of seapens in the region as sampled by Alfredo trawl gear in the Eastern Arctic biogeographic zone. A 0.25 kg minimum threshold for the sea pen catch was identified as the weight that separated the sea pen field habitat from the broader distribution of sea pens with these research vessel tow data and gear type.
Ontario Hydro Network - Hydrographic Poly
A feature is a representation of a real world object, such as a lake, stream, dam or rapid. There are three hydrographic feature classes: points, lines and polys. All may impede or be hazardous to waterflow and/or navigation on a watercourse or waterbody. This data shows natural and manmade poly features. Examples include: * break walls * dams * rapids * shipwrecks [Technical Bulletin: Data migrated to new Ontario Hydro Network (OHN) - Hydrographic Feature Data Classes (PDF)](http://geo2.scholarsportal.info/proxy.html?http:__maps.scholarsportal.info/files/PDFS/public/OGDE/OHN/TB-OHN-PostMigration_101112.pdf)
Phytoplankton pigments along the west coast of Vancouver Island
Phytoplankton pigments, determined by high-performance liquid chromatography (HPLC) have been measured on DFO La Perouse cruises since 2011. Surface samples are taken along a series of transects off the west coast of Vancouver Island twice a year usually in May/June and early September.
Inventory of macroalgae and benthic macroinvertebrates on the north shore of the Saint-Lawrence Estuary (2019)
This inventory, conducted from September 26th to October 3th, 2019, aimed to describe the community structure of macroalgae and benthic macroinvertebrates of five small estuaries of the Upper North Shore of Quebec, namely Barthélemy Bay and the Colombier, Mistassini, Franquelin and Saint-Nicolas rivers. This inventory is part of a doctoral study of Valentine Loiseau on the global changes in the St. Lawrence system, mainly the study of marine benthic communities in response to changes of salinity, to ensure proper management of the environment in the face of future changes. The main objective is to describe the structure and the levels of specific diversities of mediolittoral communities of benthic macroinvertebrates and macroalgae along a salinity gradient. These five small estuaries were selected because of their similar size, hard substrates and easy access. Three levels of hypoosmotic stress (low, medium, high) and one control level (seawater) were used for each of the selected estuaries, with eight quadrats per stress level. Quadrat positions were randomly selected but had to meet two criteria: (1) regular height in the foreshore to control the influence of other stresses (temperature, exposure); and (2) presence of at least one macroalga to maintain homogeneity. A percentage cover by macroalgal and macroinvertebrate species was estimated, and then all organisms were weighed by species and size group. The salinity of the nearest water point was measured at mid-tide with a portable refractometer and a Castaway-type CTD (Conductivity-Temperature-Density) probe. The inventory was done using a stratified random sampling design and the sampling unit was a quadrat measuring 25 x 25 cm. The three files provided (DarwinCore format) are complementary and are linked by the "eventID" key. The "event_information" file includes the generic information of the quadrat, including date and location. The "additional_information_event_and_occurrence" file includes salinity and substrate type of the quadrat, as well as the total weight of all individuals of the same species caught in the quadrat extrapolated to one square metre of surface. For nudibranchs and barnacles, weight was estimated from the size of the individuals so that they were not removed from the environment. The "taxon_occurrence" file includes the taxonomic inventory of macroalgal and benthic macroinvertebrate species observed in the quadrat, identified to the lowest possible species or taxonomic level and biomass by identified species.For quality control, organisms were identified on the field using the following guide: Chabot, Robert et Anne Rossignol. 2003. Algues et faune du littoral du Saint-Laurent maritime : Guide d'identification. Institut des Sciences de la mer de Rimouski, Rimouski ; Pêches et Océans Canada (Institut Maurice-Lamontagne), Mont-Joli. 113 pages. The taxonomy was checked against the World Register of Marine Species (WoRMS) to match recognized standards and using the R obistools and worrms libraries. The WoRMS match was placed in the "scientificNameID" field of the occurrence file. All sample locations were spatially validated. This project was funded by DFO Coastal Environmental Baseline Program under Canada’s Oceans Protection Plan. This initiative aims to acquire environmental baseline data contributing to the characterization of important coastal areas and to support evidence-based assessments and management decisions for preserving marine ecosystems.
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