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Variation in blubber cortisol as a measure of stress in beluga whales of the Canadian ArcticTrana, Marci Renée 11 April 2014 (has links)
Exposure to stressors in free-living mammals can be measured via glucocorticoid hormones concentrations. Using adipose from marine mammals (blubber) as a tissue for extracting cortisol provides a means for measuring cortisol concentrations not associated with capture stress. Beluga whale range is limited to the Arctic where climate change is exaggerated. Our objectives were to compare cortisol concentrations among archived blubber samples with varying quality and blubber depth, compare blubber cortisol from beluga whales in a high-stress entrapment event to whales harvested during subsistence hunts, and compare blubber cortisol among beluga whale populations in relation to conservation status, diet, sex, age and year sampled. Blubber samples showing signs of deterioration had lower cortisol concentrations. The deepest blubber contained the highest concentration of cortisol compared to other depths. Blubber cortisol concentrations from entrapped whales were higher than from harvests. Blubber cortisol was higher in the threatened population when compared to healthy populations.
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Comprehensive Video Ethogram on Beluga (Delphinapterus leucas) BehaviorCampbell, Carolyn Ann 2011 May 1900 (has links)
Research is limited for belugas in both the wild and in the care of humans. To address this lack of knowledge, I created a comprehensive video ethogram of beluga behavior, collected from the beluga population located at Sea World San Antonio.
The purpose of this study was to create an educational tool to train future research observers and to increase public awareness. Video recordings were taken from above water and then imported into video editing software. A total of 103 videos were reviewed, which represented 24 hours 49 minutes of video data. Each video was examined for the best examples of each behavior of interest. Clips of these behaviors were recorded and edited together into a single video paired with a voiceover commentary to explain the clip. The video ethogram comprises 82 percent of the behaviors in the comprehensive ethogram. A total of 268 clips of behaviors are in the video. The full running length of the video ethogram is 1 hour 5 minutes 2.03 seconds. Of all the potential behaviors, 64 percent were found to be frequent and 36 percent were found to be rare. The video portion provides visual examples of the behavior while the voiceover commentary provides explanations.
Due to the lack of a comprehensive ethogram in the literature and time consuming process of training observers, this video ethogram is a necessary and practical addition to the study of belugas.
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Understanding the evolution of Beluga entrapment co- management in the Inuvialuit Settlement Region using Social Network AnalysisKocho-Schellenberg, John-Erik 24 September 2010 (has links)
Co-management of fisheries in the Inuvialuit Settlement Region (ISR) began with the
establishment of the Fisheries Joint Management Committee (FJMC) in 1986, one of the
provisions of the Inuvialuit Final Agreement (IFA) signed in 1984. The agreement
between the Inuvialuit and the Canadian Government with regards to renewable resource
management was arranged as a collaborative management process that included
knowledge and insight from both sides. This thesis uses the case of beluga entrapment in
the Husky Lakes, NWT, to explore how co-management between the Tuktoyaktuk
Hunter and Trapper Committee (HTC) and the Department of Fisheries and Oceans
(DFO) has changed through time in structure and process, and to determine what impacts
co-management has had on Inuvialuit involvement in management. Additionally, the
linkage between co-management and adaptive capacity at the local level is analyzed in
order to better understand how Inuvialuit involvement in fisheries management can have
beneficial impacts on cultural preservation, youth education, and employment. This study
employed the use of mixed qualitative and quantitative methods within a participatory
approach, which aimed at including the community of Tuktoyaktuk in every step of the
research process. Qualitative methods included informal discussions, semi-directed
interviews, participant observation, and document analysis. Community research partners
were also essential in accessing information and interviews. The quantitative method
used in this study was the use of questionnaires for Social Network Analysis (SNA) in
attempting to describe the changes in the management network over time.
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Understanding the evolution of Beluga entrapment co- management in the Inuvialuit Settlement Region using Social Network AnalysisKocho-Schellenberg, John-Erik 24 September 2010 (has links)
Co-management of fisheries in the Inuvialuit Settlement Region (ISR) began with the
establishment of the Fisheries Joint Management Committee (FJMC) in 1986, one of the
provisions of the Inuvialuit Final Agreement (IFA) signed in 1984. The agreement
between the Inuvialuit and the Canadian Government with regards to renewable resource
management was arranged as a collaborative management process that included
knowledge and insight from both sides. This thesis uses the case of beluga entrapment in
the Husky Lakes, NWT, to explore how co-management between the Tuktoyaktuk
Hunter and Trapper Committee (HTC) and the Department of Fisheries and Oceans
(DFO) has changed through time in structure and process, and to determine what impacts
co-management has had on Inuvialuit involvement in management. Additionally, the
linkage between co-management and adaptive capacity at the local level is analyzed in
order to better understand how Inuvialuit involvement in fisheries management can have
beneficial impacts on cultural preservation, youth education, and employment. This study
employed the use of mixed qualitative and quantitative methods within a participatory
approach, which aimed at including the community of Tuktoyaktuk in every step of the
research process. Qualitative methods included informal discussions, semi-directed
interviews, participant observation, and document analysis. Community research partners
were also essential in accessing information and interviews. The quantitative method
used in this study was the use of questionnaires for Social Network Analysis (SNA) in
attempting to describe the changes in the management network over time.
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Beluga whale, Delphinapterus leucas, vocalizations and their relation to behaviour in the Churchill River, Manitoba, CanadaChmelnitsky, Elly 13 September 2010 (has links)
The investigation of a species’ repertoire and the contexts in which different calls are used is central to understanding vocal communication among animals. Beluga whale, Delphinapterus leucas, calls were classified and described in association with behaviours, from recordings collected in the Churchill River, Manitoba, during the summers of 2006-2008. Calls were subjectively classified based on sound and visual analysis into whistles (64.2% of total calls; 22 call types), pulsed or noisy calls (25.9%; 15 call types), and combined calls (9.9%; seven types). A hierarchical cluster analysis, using six call measurements as variables, separated whistles into 12 groups and results were compared to subjective classification. Beluga calls associated with social interactions, travelling, feeding, and interactions with the boat were described. Call type percentages, relative proportions of different whistle contours (shapes), average frequency, and call duration varied with behaviour. Generally, higher percentages of whistles, more broadband pulsed and noisy calls, and shorter calls (<0.49s) were produced during behaviours associated with higher levels of activity and/or apparent arousal. Information on call types, call characteristics, and behavioural context of calls can be used for automated detection and classification methods and in future studies on call meaning and function.
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Beluga whale, Delphinapterus leucas, vocalizations and their relation to behaviour in the Churchill River, Manitoba, CanadaChmelnitsky, Elly 13 September 2010 (has links)
The investigation of a species’ repertoire and the contexts in which different calls are used is central to understanding vocal communication among animals. Beluga whale, Delphinapterus leucas, calls were classified and described in association with behaviours, from recordings collected in the Churchill River, Manitoba, during the summers of 2006-2008. Calls were subjectively classified based on sound and visual analysis into whistles (64.2% of total calls; 22 call types), pulsed or noisy calls (25.9%; 15 call types), and combined calls (9.9%; seven types). A hierarchical cluster analysis, using six call measurements as variables, separated whistles into 12 groups and results were compared to subjective classification. Beluga calls associated with social interactions, travelling, feeding, and interactions with the boat were described. Call type percentages, relative proportions of different whistle contours (shapes), average frequency, and call duration varied with behaviour. Generally, higher percentages of whistles, more broadband pulsed and noisy calls, and shorter calls (<0.49s) were produced during behaviours associated with higher levels of activity and/or apparent arousal. Information on call types, call characteristics, and behavioural context of calls can be used for automated detection and classification methods and in future studies on call meaning and function.
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The good, the bad and the ugly: lessons learned from vitamins, persistent organic pollutants, and the interaction of the two in western Arctic beluga whalesDesforges, Jean-Pierre 04 April 2013 (has links)
Many of the factors that shape contaminant accumulation profiles in marine mammals also strongly influence fat soluble vitamin accumulation. Vitamin A and E are essential fat soluble nutrients for numerous biological processes, including reproduction, growth, endocrine and immune function. Contaminants, such as polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs), can alter vitamin dynamics; as such these vitamins have been proposed as sensitive biomarkers of contaminant exposure in wildlife. In light of these considerations, the present thesis was aimed at better understanding the factors that influence the accumulation of lipophilic contaminants and vitamins in western Arctic beluga whales, and to determine if there was an interaction between the two.
Maternal offloading to neonates during gestation reduced overall contaminant (PCBs and PBDEs) and vitamin (A and E) concentrations in reproductively active female whales. The PCB and PBDE congener pattern in mothers changed during gestation as a result of preferential transfer of light-low Log KOW congeners to the fetus. Overall, female beluga whales transferred approximately 11% of their PCB and PBDE blubber burden to their fetus. In terms of vitamins transfer, lower concentrations of tocopherols, retinol and retinyl esters were found in reproductively active females relative to males and reproductively inactive females. Metabolism was also found to be an important factor for contaminant and vitamin accumulation in beluga tissues. In a principal components analysis, PCBs clustered into metabolically-derived structure-activity groups, which separated along the first principal component according to its metabolic potential (metabolizable vs. recalcitrant). Contaminant-related up-regulation of metabolizing enzymes, including cytochrome P450, likely explained changes in the concentration and pattern of PCB and PBDE congeners, as well as hepatic, plasma, and blubber vitamin A and E.
Since vitamins and lipophilic contaminants accumulated in beluga whales in the same way in relation to most biological processes, including sex, reproduction, size, condition, and feeding ecology, it was important to control and reduce the number of these confounding factors before claiming any tissue vitamin change was indeed the result of chemical exposure. In doing so, it was found that vitamin A and E homeostasis was influenced by PCBs in beluga whales, resulting in reduced hepatic storage and increased plasma and blubber concentrations. Overall, these results suggest that liver, plasma, and inner blubber vitamin A and E concentrations can be sensitive biomarkers of contaminant exposure only if major confounding effects are taken into consideration. The implications of altered vitamin dynamics on the health of beluga whales is unknown at this time; however, as Arctic marine mammals face continued stress related to climate change, increased human disturbance and emergence of infectious diseases, this study can serve as essential baseline data that can be used to monitor the health status of western Arctic beluga whales. / Graduate / 0383 / 0329 / 0768 / jpdesforges@gmail.com
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Population Genetic Structure of Beluga Whales Delphinapterus leucus Mitochondrial DNA Sequence Variation Within and Among North American Populations / Population Genetic Structure of Beluga WhalesBrennin, Ree January 1992 (has links)
Beluga whales are migratory over much of their range, congregating in small groups around shallow river estuaries in summer, and overwintering in large groups in areas with reliable open water. This complicates management issues because it is unclear if belugas from the common wintering ground represent one large group with exchange of individuals, or if each summer estuarine concentration should be managed as a separate stock. To examine the genetic structuring, we analyzed variation in mitochondrial DNA (mtDNA) restriction sites among 101 beluga whales from 10 regions across North America, including Greenland. Using 11 restriction enzymes, 9 haplotypes were identified among 71 whales. The remaining 30 whales were tested with only the six restriction enzymes found to identify polymorphisms. We found a marked segregation of divergent haplotypes for both sexes between eastern and western Hudson Bay. Haplotype 1 was found in 19 out of 21 animals on the east coast, while haplotype 5 was found in 18 out of 20 animals on the west coast. Sequence divergence among the 71 belugas was estimated to be 2.03%. Haplotypes fell into two major phylogenetic groups, labelled lineage I and II. Lineage I haplotypes occurred primarily in the St. Lawrence Estuary and the eastern Hudson Bay. Lineage II haplotypes occurred primarily along the western Hudson Bay, Southern Baffin Island, western Greenland, the Canadian high arctic, and the Beaufort Sea. These findings support the hypothesis that belugas exhibit maternally directed philopatry to summering grounds, and are consistent with the hypothesis that after deglaciation, the arctic was recolonized by at least two stocks of belugas divergent in their mtDNA, possibly representing Atlantic and Pacific stocks. / Thesis / Master of Science (MS)
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Tethered balloon measurements during Arctic spring conditions in Ny-Ålesund in the framework of HALO-(AC)3Lonardi, M., Ehrlich, A., Müller, J., Saavedra Garfias, P., Wendisch, M. 08 December 2023 (has links)
The tethered balloon system BELUGA (BalloonbornE moduLar Utility for
profilinG the lower Atmosphere) was operated in spring 2022 at the AWIPEV research
station (Ny-Ålesund, Svalbard). In-situ profiles of thermodynamic parameters, thermalinfrared
radiation, aerosol particle concentrations, and turbulence, were measured and
analyzed. Additionally, samples of ice-nucleating particles were collected at various
heights. In combination with previous BELUGA datasets, measurements from this
campaign provide a solid base for studying the vertical profiles of the radiative energy
budget and heating rates in different atmospheric states in the Arctic lower troposphere.
Here, example thermal-infrared radiation profiles are presented for a period of persisting
cloudless conditions related to a series of marine cold air outbreaks in late March/early
April. Measurements in clouds are analyzed for a developing cloud observed on 6 May
and display the impact of cloudiness on radiation profiles. / Das Fesselballonsystem BELUGA (BalloonbornE moduLar Utility
for profilinG the lowerAtmosphere) wurde im Frühjahr 2022 an der Forschungsstation
AWIPEVStation (Ny-Ålesund, Svalbard) eingesetzt. In-situ-Profile von thermodynamischen
Parametern, terrestrische Strahlung, Aerosolpartikelkonzentrationen und Turbulenz
wurden gemessen und ausgewertet. Zusätzlich wurden in verschiedenen Höhen Proben
von eiskeimbildenden Partikeln gesammelt. In Kombination mit früheren BELUGA
Messungen zu anderen Jahreszeiten und an anderen arktischen Messstandorten bieten die
Messungen in Ny-Ålesund eine Grundlage fürweitereUntersuchungen des Strahlungsenergiehaushalts
und des Einflusses vonWolken auf atmosphärische Heizraten. Profile der
Strahlungsbilanz werden für eine anhaltende Kälteperiode zwischen Ende März bis Anfang
April 2022 vorgestellt. Über diesen Zeitraum herrschten vor allem wolkenlose
Bedingungen. Weitere Beobachtungen unter einer sich entwickelnden Wolkendecke am
6. Mai 2022 zeigen den Einfluss der Bewölkung auf die Strahlungsprofile.
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Bioaccumulative contaminants in marine mammals: uptake and effectsNoel, Marie 12 April 2013 (has links)
This thesis provides insights into the transport and fate of contaminants of concern (polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and mercury (Hg)), as well as results on the impacts of these compounds on marine mammal health.
Atmospheric transport is known to be a significant pathway for the delivery of contaminants to remote food webs. Air and rain samples were collected from one remote site on the west coast of Vancouver Island, British Columbia (BC), Canada, and from one near-urban site in the Strait of Georgia, BC. While global atmospheric dispersion was observed for the legacy PCBs, 40% of PBDEs detected in BC air appeared to be originating from trans-Pacific transport. It was estimated that 3kg of PCBs and 17kg of PBDEs were deposited every year in the Strait of Georgia.
Once deposited, PCBs, PBDEs and Hg biomagnify up the food chain. Harbour seals are non-migratory and can be used to provide signals of local contaminant sources. They have been extensively used as indicators of PCB and PBDE food web contamination in the BC coastal environment. The collection of over 200 harbour seal fur samples from various locations around Vancouver Island, BC and Puget Sound, WA, USA helped us pinpoint three sites where Hg levels were significantly higher than our reference site, Bella Bella (Queen Charlotte Strait, Port Renfrew and central Puget Sound). A combination of anthropogenic sources and marine food web processes appeared to influence the delivery of methylmercury (MeHg) to the top of this coastal marine food chain. Our results also suggested that these Hg levels (1.6-46.9 µg/g) could be a concern for the health of these harbour seals.
Genomic techniques were used to generate insights into the implications of contaminant exposure on the health of marine mammals inhabiting industrialized regions (harbour seals from the Northeastern Pacific and Northwestern Atlantic) and remote, supposedly pristine, environment (Arctic beluga whales). In harbour seal blubber, there were positive correlations between the mRNA levels of several genes, including estrogen receptor alpha (Esr1), thyroid hormone receptor alpha (Thra), and glucocorticoid receptor (Nr3c1), and PCB levels. In beluga blubber, aryl hydrocarbon receptor (Ahr) and cytochrome P450 (Cyp1a1) mRNA levels increased with PCBs, consistent with their role in toxicity.While PCB-related toxic responses were observed in both species, additional factors appeared to be affecting the expression of important genes in beluga. Our results suggested that a shift in beluga diet during periods of low sea ice extent, as evidenced by changes in δ13C isotope ratios, had a significant impact on mRNA levels coding for genes involved in growth, metabolism and development.
The use of a dual study design to evaluate the long range versus local sources of contaminants highlighted the importance of trans-Pacific transport in the delivery of PBDEs to coastal BC and the occurrence of local Hg sources in this marine environment. However, consistent with previous studies, our results suggested that PCBs remain the top contaminant of concern for marine mammal health. We also raised questions about the potential exacerbation of toxic risks due to PCBs as a consequence of climate changes currently underway in the Arctic. / Graduate / 0768 / 0383 / marie.t.noel@gmail.com
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