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We have found 137 datasets for the keyword " broad whitefish". You can continue exploring the search results in the list below.
Datasets: 106,156
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137 Datasets, Page 1 of 14
Mackenzie River Exploratory Fishery 1989-1993; Investigation of the Population Structure of Broad Whitefish (Coregonus nasus) and Biological Analysis and Population Assessment of Northern Pike (Esox lucius), Inconnu (Stenodus leucichthys), and Lake Whitefish (Coregonus clupeaformis)
An exploratory fishery was carried out in the Mackenzie River Delta between 1989 and 1993 at the request of the Inuvik Hunters and Trappers Committee to assess the commercial fishery potential in this area. Data collected during this exploratory fishery was used in two technical reports. Broad whitefish were the target species of this fishery (DFO Technical Report 2180), however other species such as northern pike, inconnu, and lake whitefish were also harvested (DFO Technical Report 2330).Biological data from broad whitefish (fork length, age, gonadosomatic index and instantaneous mortality) were analyzed to assess the impact of an exploratory fishery in the Mackenzie River Delta. The data were collected using variable mesh experimental gill nets and commercial harvesters' 139 mm (5.5”) mesh gill nets. The data suggest that the broad whitefish population might be separated, with larger mature spawners gathering in the main channels prior to spawning and smaller, immature or resting fish staying in side channels away from strong currents. From this analysis we conclude that the size and structure of the broad whitefish population(s) found in this area are stable at the current level of total harvest (commercial and subsistence combined) There may be room for increased harvests but to what level is uncertain.Biological data from northern pike, inconnu, and lake whitefish were analyzed to assess the impact of the fishery on population abundance and structure. All three by catch species support subsistence fisheries in the Mackenzie Delta. lnconnu and lake whitefish migrate substantial distances, crossing land claim borders and are likely fished by a variety of user groups. Northern pike, on the other hand tend to be non-migratory with localized populations that are mainly fished by people living in the near vicinity. A concern was that commercial fishing pressure might reduce the numbers of fish available to subsistence users. Based on trends in size and age frequency, age at maturity, sex ratio, growth rates, and mortality rates, we conclude that inconnu and lake whitefish populations in the Mackenzie Delta have remained healthy and stable at the current harvest levels, however northern pike populations showed a decrease in the proportion of older fish, possibly indicating over-fishing of local stocks. lnconnu and lake whitefish may be able to withstand increased harvest, but to what extent is unknown, given that little reliable information is available on subsistence harvest levels in this region. Increasing harvest levels of pike may be risky and we suggest that a reduction of current commercial harvest quotas be considered.
Broad Ecosystem Units - West Central Region
Broad Ecosystem Units were mapped using predictive modeling methods from various data sources (ranging from 1:50,000 to 1:250,000 in scale) and are referenced to the CanVec digital spatial framework (1:50,000). Broad Ecosystem Units (BEU) are a level in the Yukon bioclimate ecosystem classification system that represents areas with similar broad vegetation communities, terrain type (soils and topography) within bioclimate zones. Broad Ecosystem Units are described in the accompanying report "Regional Ecosystems of West-Central Yukon, Part 1: Ecosystem descriptions ".The intended application for mapped broad ecosystem units is 1:100,000 or smaller (1:100,000 - 1:250,000 scale) - interpretations derived from the map products should not be applied at more detailed scales, even though the resultant 30m raster map allows users to view results at more detailed resolutions. With new information, boundaries and designations of Broad Ecosystem Units can change. Updates to Broad Ecosystem Units occur only periodically. For the most current information, or if you have questions, please contact the Ecological and Landscape Classification Program (ELC@yukon.ca).Distributed from [GeoYukon](https://yukon.ca/geoyukon) by the [Government of Yukon](https://yukon.ca/maps) . Discover more digital map data and interactive maps from Yukon's digital map data collection.For more information: [geomatics.help@yukon.ca](mailto:geomatics.help@yukon.ca)
Ecodomains - Ecoregion Ecosystem Classification of British Columbia
Ecodomains are areas broad climatic uniformity, defined at the global level
Ecodivisions - Ecoregion Ecosystem Classification of British Columbia
Ecodivisions are areas of broad climatic and physiographic uniformity, defined at the continental level.
Ground ice map of Canada - segregated ice
The mapping depicts the relative abundance of segregated ice in upper permafrost at a national scale. The mapping is based on modelling by O'Neill et al. (2019) (https://doi.org/10.5194/tc-13-753-2019). The mapping offers an improved depiction of ground ice in Canada at a broad scale, incorporating current knowledge on the associations between geological and environmental conditions and ground ice type and abundance. It provides a foundation for hypothesis testing related to broad-scale controls on ground ice formation, preservation, and melt.
Ground ice map of Canada - wedge ice
The mapping depicts the relative abundance of wedge ice in upper permafrost at a national scale. The mapping is based on modelling by O'Neill et al. (2019) (https://doi.org/10.5194/tc-13-753-2019). The mapping offers an improved depiction of ground ice in Canada at a broad scale, incorporating current knowledge on the associations between geological and environmental conditions and ground ice type and abundance. It provides a foundation for hypothesis testing related to broad-scale controls on ground ice formation, preservation, and melt.
Ground ice map of Canada - relict ice
The mapping depicts the relative abundance of relict (buried glacier) ice preserved in upper permafrost at a national scale. The mapping is updated and based on modelling by O'Neill et al. (2019) (https://doi.org/10.5194/tc-13-753-2019). The mapping offers an improved depiction of ground ice in Canada at a broad scale, incorporating current knowledge on the associations between geological and environmental conditions and ground ice type and abundance. It provides a foundation for hypothesis testing related to broad-scale controls on ground ice formation, preservation, and melt.
Ground ice map of Canada
The mapping depicts a first-order estimate of the combined volumetric percentage of excess ice in the top 5 m of permafrost from segregated, wedge, and relict ice. The estimates for the three ice types are based on modelling by O'Neill et al. (2019) (https://doi.org/10.5194/tc-13-753-2019), and informed by available published values of ground ice content and expert knowledge. The mapping offers an improved depiction of ground ice in Canada at a broad scale, incorporating current knowledge on the associations between geological and environmental conditions and ground ice type and abundance. It provides a foundation for hypothesis testing related to broad-scale controls on ground ice formation, preservation, and melt.
National Human Settlement - Social Fabric and Capacity Thresholds
The Social Vulnerability component of the National Human Settlement Layer (NHSL) includes information about broad spatial patterns of social vulnerability at the neighbourhood scale, and indicators about the capacities for a community to withstand and recover from disaster events based on intrinsic characteristics of housing, family structure, individual autonomy and financial agency.Information in the model provides a means of comparing relative levels of social vulnerability from one region to another across Canada and helps to identify specific dimensions within a community that contributes to their relative levels of social vulnerability. This information is not intended for site-specific study, but instead to understand broad patterns of social characteristics and vulnerability across multiple census dissemination areas.
Broad-leaved species in Canada 2011
The raster maps depict a suite of forest attributes in 2001* and 2011 at 250 m by 250 m spatial resolution. The maps were produced using the k nearest neighbours method applied to MODIS imagery and trained from National Forest Inventory photo plot data. For detailed information about map production methods please refer to Beaudoin et al. (2018) "Tracking forest attributes across Canada between 2001 and 2011 using the k nearest neighbours mapping approach applied to MODIS imagery." Canadian Journal of Forest Research 48, 85-93. https://cfs.nrcan.gc.ca/publications?id=38979 The map datasets may be downloaded from https://nfi.nfis.org/downloads/nfi_knn2011.zip or https://open.canada.ca/data/en/dataset/ec9e2659-1c29-4ddb-87a2-6aced147a990 * Note: the forest composition (leading tree genus) map depicts forest attributes in 2001.How can this data be used?The resolution and accuracy of these map products are best suited for strategic-level forest reporting and informing policy and decision making at regional to national scales. As these maps also offer a coherent set of quantitative values for a large suite of forest attributes, they can be used as baseline information for modelling and in calculations such as merchantable forest volume or percentage of tree species. It is also possible to overlay these maps with other maps produced on the same pixel grid to make assessments of disturbance impacts, such as fire and harvests.
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