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We have found 50 datasets for the keyword " pleuronectidae". You can continue exploring the search results in the list below.
Datasets: 106,031
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50 Datasets, Page 1 of 5
Steller sea lion (Eumetopias jubatus) counts and haulout locations across the British Columbia coast
Considered the "king" of sea lions, the Steller sea lion (Eumetopias jubatus) is the biggest of all sea lions and enjoys a lifespan of up to thirty years. In Canada, the Steller can be spotted along the rocky coast of British Columbia. This hefty mammal usually travels alone or in a small group, but wisely, it joins others for protection during the mating and birthing season. Little is known about its oceanic lifestyle; however, the good news for this sea-loving mammal is that since the Steller sea lion first became protected in 1970, the size of the adult population has more than doubled. Recent trends in the abundance of Steller sea lions (Eumetopias jubatus) in British Columbia were assessed based on a series of thirteen province-wide aerial surveys conducted during the breeding season (27-June to 06-July) between 1971 and 2013.
Steller Sea Lion Haulout Counts in British Columbia
The Steller sea lion (Eumetopias jubatus) is the largest of all sea lions and enjoys a lifespan of up to thirty years. In Canada, the Steller can be spotted along the rocky coast of British Columbia. These highly mobile marine mammals typically travel alone or in small groups, but they congregate in large numbers at traditional rookeries and haul-outs during the mating and pupping season. The population was severely depleted in Canada but following its protection in 1970, the size of the adult population has more than doubled.The survey targeted Steller sea lions and sites were chosen based on knowledge of historically occupied rookeries and haul-out sites with nearby areas monitored for potential shifts in distribution. This dataset contains counts that have been collected from sightings of individuals in the 2016/2017 survey season.
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
Harbour seal (Phoca vitulina) counts and haulout locations along BC coast
Harbour seals (Phoca vitulina) are found along temperate and Arctic marine coastlines of the Northern Hemisphere. They are found in coastal waters of the northern Atlantic and Pacific Oceans, as well as those of the Baltic and North Seas. In Canada, they may be found off the coastal waters of British Columbia, Nunavut, Manitoba, Ontario, Quebec, New Brunswick, Prince Edward Island, Nova Scotia, and Newfoundland and Labrador.Population trends and abundance of harbour seals in British Columbia are assessed based on aerial surveys conducted during 1966-2019. Based on counts conducted in Index Areas distributed throughout the province, the trend observed in the Strait of Georgia appears to be generally indicative of harbour seal populations throughout British Columbia. Total abundance of harbour seals on the B.C. coast in 2008 was estimated to be on the order of about 105,000 (95% confidence interval of 90,900 to 118,900) seals. Total abundance was re-estimated in 2022 (estimate and CI pending completion of CSAS process). Historic reconstructions indicate the population was depleted by a period of commercial harvesting during 1879-1914, and subsequently maintained below natural levels by predator control programs until the early 1960s. Already depleted, the population could not sustain a second period of intense commercial harvesting during 1962-1968 and was further depleted, but now appears to have fully recovered.
Scientific trawl surveys of American lobster (Homarus americanus) and rock crab (Cancer irroratus) in the Magdalene Island
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
Coleophora laricella
Historical finds of Coleophora laricella
Marine mammal records collected by the At-Sea Observer program in Arctic, Newfoundland and Labrador and Maritimes regions
Records of marine mammal sightings (N = 5,324) collected by ASOs and submitted to Fisheries and Oceans Canada (DFO) between 1979-2024, across three DFO regions: the Arctic, Newfoundland and Labrador, and the Maritimes. Methods for initial data compilation are provided in the associated technical report "Marine mammal records collected by the at-sea observer (ASO) program in Arctic, Newfoundland and Labrador, and Maritimes regions: a summary of challenges and opportunities for future research." Cite this data as: Feyrer, L.J., Colbourne, N., Lawson, J.W., Moors-Murphy, H.B., Ferguson, S. Dataset update to Marine mammal records collected by the At-Sea Observer program in Arctic, Newfoundland and Labrador and Maritimes regions. Published: February 2025. Ocean Ecosystems Science Division, Fisheries and Oceans Canada, Dartmouth, N.S.
Operophtera brumata
Historical finds of Operophtera brumata
Sightings, Strandings, and Entrapment Data For Sea Turtles in Newfoundland and Labrador, Canada
The data in this dataset represent an amalgamation of sea turtle sighting, stranding, and entrapment events, mainly near Newfoundland and Labrador (NL), Canada.This document summarises the detection events data for Leatherback (Dermochelys coriacea), Loggerhead (Caretta caretta), and Green (Chelonia mydas) Turtles that has been collected from opportunistic and systematic survey sources, plus stranding and entrapment records, in the waters of NL from 1946 to 2023. To a much lesser extent there are also detection records for the southern Gulf of St. Lawrence. Scotian Shelf, and northeastern U.S. waters.These detection records are mostly derived from opportunistic reports, so there are rarely data for a report that includes measures of the observer effort expended to make the detection, and rarely associated imagery. During DFO aerial surveys there are measures of effort in most cases, enabling the turtle sightings reports to be used in habitat modelling (e.g., Mosnier et al. 2018).Most of the information variables (such as “Date”, “Latitude”, “Longitude”, “Number of Animals”) have been obtained from the detection report. In some cases data for variables such as “Location Reliability”, “ID Reliability”, “Platform”, and “Strand or Entrapment Outcome” were derived from interpretation of the comments associated with the report, if available. For description of the variables in the dataset see the Data Dictionary.References:Mosnier, A., Gosselin, J.-F., Lawson, J., Plourde, S., and Lesage, V. 2018. Predicting seasonal occurrence of leatherback turtles (Dermochelys coriacea) in eastern Canadian waters from turtle and sunfish (Mola mola) sighting data and habitat characteristics. Can. J. Zool. 97: 464-478. https://doi.org/10.1139/cjz-2018-0167
Blue whale - Trajectories and locations of Area-Restricted Search
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.
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