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Killer whale range expansion and extended seasonal presence in the eastern Canadian Arctic, 2002-2023
PURPOSE: The focus of this research is on changes in the distribution of killer whales in the Canadian Arctic, which is within the field of marine biogeography and marine megafauna. Our research details change in killer whale presence and ties it to changes in sea ice coverage. These are novel results, presenting trends in the arrival and departure dates of killer whales into the eastern Canadian Arctic for the first time. We go on to discuss the impacts of these changes on other aspects of Arctic ecosystems and how increasing in killer whale presence might affect other species and the management of those species in Canada. Killer whales are a widespread species of interest, especially in the Canadian Arctic as their presence is tied to multiple aspects of a region rapidly changing from the effects of climate change. DESCRIPTION: This study examines 20 years of killer whale (Orcinus orca) sightings in the eastern Canadian Arctic, drawing from a comprehensive sighting database spanning 1850-2023. Despite inherent biases favoring data collection near communities and coastal areas, spatiotemporal analyses reveal significant shifts in killer whale distribution linked to changing sea ice conditions. We developed a clustering metric representing the mean distance to the five nearest sightings and results show that killer whales are progressively moving away from historically high-use areas and that sighting locations are becoming more dispersed over time. A significant year × sea ice interaction indicates observations occur earlier during their arrival period at lower sea ice concentrations over time, suggesting that declining sea ice concentration contributes to earlier arrival. Conversely, for departure periods, killer whales are observed farther south later in the year, likely linked to earlier freeze-up at higher latitudes, and are overall observed later into the year over time. This trend has led to a near doubling of their average presence from 26 days in 2002 to 48 days in 2023 (27 July to 13 September) reflecting an extended open-water season. These findings underscore the prolonged seasonal use of Arctic regions by killer whales, driven by diminishing sea ice and expanding openwater habitat. Such shifts highlight potential implications for Arctic marine ecosystems as killer whales increasingly overlap with endemic species.
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Winter occurrence of killer whale populations off eastern Vancouver Island, British Columbia (2015-2018)
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This study constitutes the first quantitative assessment of winter use of the northern Strait of Georgia by killer whales, which presents a substantial contribution to the limited knowledge of killer whale habitat use in British Columbia during the winter. Passive acoustic monitoring revealed extensive use of this area by three sympatric killer whale populations from November to April over three seasons. This study also evaluated the effect of using multiple simultaneous acoustic recorders to characterize killer whale habitat use, and developed a data-driven approach to define acoustic residency time.
AFSC/NMML: Killer whale surveys in the Aleutian Islands, Bering Sea, and western and central Gulf of Alaska, 2001 - 2010
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This dataset is a compilation of line-transect data collected on surveys in the Aleutian Islands, Bering Sea, and western and central Gulf of Alaska, 2001 - 2010. All the surveys were conducted with similar methods using line-transect protocols, allowing effort to be quantified, but there were differences in transect design in some years (some surveys were systematic, some were not). Sighting information for all cetacean and at-sea pinniped species was collected. The database was compiled with the intent of including all surveys with sighting data on killer whales, in order to assess killer whale population biology in this region. Surveys included in this database are 2001 - 2007, 2009 and 2010 NMML killer whale surveys.
AFSC/NMML: Killer Whale encounter data in the Aleutian Islands, Bering Sea, and the western and central Gulf of Alaska from 2000 - 2010
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Comprises data from surveys focused on killer whales with opportunistic data from other cetacean species; includes data describing encounters for photo-identifications, biopsy, and acoustic sampling. Data includes surveys conducted by CAEP/NMML, and also contributed data from Alaska Ecosystem Program/NMML, Southwest Fisheries Science Center and other collaborators. Surveys were conducted in the Aleutian Islands, Bering Sea, and western Gulf of Alaska, 2000 to the present.
Killer whale surveys conducted in the Aleutian Islands, Bering Sea, and western and central Gulf of Alaska by Alaska Fisheries Science Center, National Marine Mammal Laboratory from 2001-07-01 to 2010-07-12 (NCEI Accession 0137766)
공공데이터포털
This dataset is a compilation of line-transect data collected on surveys in the Aleutian Islands, Bering Sea, and western and central Gulf of Alaska, 2001 - 2010. All the surveys were conducted with similar methods using line-transect protocols, allowing effort to be quantified, but there were differences in transect design in some years (some surveys were systematic, some were not). Sighting information for all cetacean and at-sea pinniped species was collected. The database was compiled with the intent of including all surveys with sighting data on killer whales, in order to assess killer whale population biology in this region. Surveys included in this database are 2001 - 2007, 2009 and 2010 NMML killer whale surveys.
AFSC/NMML: North Pacific Killer whale genetic dataset, 1990-2010
공공데이터포털
The difficulties associated with detecting population boundaries have long constrained the conservation and management of highly mobile marine species, especially for wide-ranging cetaceans such as killer whales (Orcinus orca). In this study, we use molecular genetic data to test a priori hypotheses about population subdivisions generated from a decade of killer whale surveys across the northern North Pacific. A total of 462 skin biopsies were collected from free-swimming killer whales from 1990 to 2010 between the northern Gulf of Alaska in the east and the Sea of Okhotsk in the west, representing both the piscivorous resident and the mammal-eating Biggs (or transient) killer whales. Geographic patterns of genetic differentiation were supported by significant regions of genetic discontinuity providing evidence of population structuring within both lineages, and corroborating direct observations of restricted movements of individual whales. In the Aleutian Islands (Alaska), population strata were largely delimited by major oceanographic boundaries for resident killer whales. In contrast, subdivisions among Biggs killer whales indicated multiple genetic clusters in the Eastern Aleutians and Bering Sea. The presence of sympatric genetic clusters within Biggs whales suggests the presence of isolating mechanisms other than geographic distance within this highly mobile top predator.
Killer whale morphology - Variation in morphology of killer whale ecotypes
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We are using elliptic Fourier analysis to determine the patterns of variation in morphology of dorsal fin shape, saddle patch shape, and eye patch shape of resident, transient, and offshore killer whales in the northeastern Pacific ocean. We will also be looking for evidence of genetic variation underlying these patterns in southern resident killer whales. Morphology and heritability of morphology by ecotype, sex (if available), age (if available), and parentage (if available).
Population abundance, trend, structure and distribution of the endangered Antarctic blue whale
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This is a parent record for data collected from AAS project 4102. Project 4102 also follows on from ASAC project 2683, "Passive acoustic monitoring of antarctic marine mammals" (see the related metadata record at the provided URL). Public Summary: Half a century ago the Antarctic blue whale was perilously close to extinction. Over 350,000 were killed before the remaining few were fully protected. A decade ago this elusive and poorly understood species was estimated to be less than 5% of its pre-whaling abundance. This multi-national, circumpolar project will develop and apply powerful new techniques to survey these rare whales and gain an insight into their recovery and ecology. The project is the flagship of the Southern Ocean Research Partnership - an International Whaling Commission endorsed collaborative program.
North Pacific killer whale genetic studies conducted by Alaska Fisheries Scientific Center, National Marine Mammal Laboratory from 1990-10-26 to 2010-07-07 (NCEI Accession 0142202)
공공데이터포털
The difficulties associated with detecting population boundaries have long constrained the conservation and management of highly mobile marine species, especially for wide-ranging cetaceans such as killer whales (Orcinus orca). In this study, we use molecular genetic data to test a priori hypotheses about population subdivisions generated from a decade of killer whale surveys across the northern North Pacific. A total of 462 skin biopsies were collected from free-swimming killer whales from 1990 to 2010 between the northern Gulf of Alaska in the east and the Sea of Okhotsk in the west, representing both the piscivorous resident and the mammal-eating Biggs (or transient) killer whales. Geographic patterns of genetic differentiation were supported by significant regions of genetic discontinuity providing evidence of population structuring within both lineages, and corroborating direct observations of restricted movements of individual whales. In the Aleutian Islands (Alaska), population strata were largely delimited by major oceanographic boundaries for resident killer whales. In contrast, subdivisions among Biggs killer whales indicated multiple genetic clusters in the Eastern Aleutians and Bering Sea. The presence of sympatric genetic clusters within Biggs whales suggests the presence of isolating mechanisms other than geographic distance within this highly mobile top predator.
SRKW seasonal occurence - Population structure and viability of SRKW and other top marine predators
공공데이터포털
The Southern Resident killer whale (SRKW) population is threatened by a number of identified risk factors including prey availability, contaminants, vessel noise and disturbance, and small population size. However, the population may also be subject to internal factors that limit population growth. Continued assessment of the discreetness of this population through morphological and genetic characteristics is important to maintaining ESA status. In addition, an annual census provides important information that allows demographic analyses of this population to be conducted in order to assess population viability. The components of the project represent a significant level of investment of base funds over many years and these data and analyses provide the foundation of information on the population against which all research and management actions are measured that are attempting to address key risk factors of the SRKW population as protected under the ESA and MMPA. Data taken seasonally.
Killer Whale Genetic Data - Incidence of inbreeding and inbreeding depression in Southern Resident Killer Whales
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The southern residents face several well-documented external threats. However, the population might also be subject to internal factors that limit population growth, including a reduction in fitness due to inbreeding. Understanding how inbreeding affects individual fitness and thus the health status of the population is critical for evaluating the relative influence of other factors on southern resident recovery. Assessing the risk of inbreeding depression – specifically called for in the NMFS recovery plan – is important for conducting accurate Population Viability Analyses and correctly understanding the urgency of recovery efforts. Here, we propose using genomic methods to evaluate inbreeding and inbreeding depression in the southern resident population and a comparable but healthier Alaskan resident population. Measures of inbreeding will serve as an important health marker, supporting the integration of individual metrics aimed at understanding population performance. Measures of inbreeding can be obtained directly by estimating variation at millions of DNA markers in an individual’s genome. Complete genomic sequences for 100 southern and 50 Alaska residents will be collected in collaboration with the genomics company BGI. Inbreeding values for each individual will be obtained using genome wide measures of homozygosity and relatedness. We will then combine measured of inbreeding with data on individual fitness, to evaluate whether inbreeding leads to inbreeding depression. Generalized additive models will be used to determine whether survivorship, fecundity and size-at-age is influenced by different levels of inbreeding. Using this data, we will measure the degree of current and predicted future of inbreeding in the southern residents and compare this risk with the Alaska residents that have experienced consistent population growth. We will then evaluate whether inbreeding depression explains individual variance in fitness, and estimate its influence on the status of southern residents, using Population Viability Analyses. Microsatellite, SNP, and mtDNA sequence data from southern resident killer whales.
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