Download or read book Spring Distribution and Habitat Use of Belugas Delphinapterus Leucas in the Eastern Beaufort Sea written by Natalie Claudette Asselin and published by . This book was released on 2011 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt: An understanding of the adaptability of belugas (Delphinapterus leucas) to changing ice-conditions is required to interpret and predict possible changes in habitat selection in response to projected loss of sea ice throughout the circumpolar Arctic. Beluga spring distribution in the eastern Beaufort Sea was described by analyzing observations from aerial surveys conducted from 1975 to 1979. Repeated surveys along the Franklin Bay fast-ice edge in June 2008 were used to study the distribution and behaviour of belugas and bowheads. Despite inter-annual variability in ice extent, belugas consistently selected areas with water depths of 200-500 m, heavy ice concentrations (8/10 to 10/10) and seafloor slope [greater than or equal to]0.5 degrees in spring 1975 to 1979. While predator avoidance may partially explain the observed distribution, foraging success likely has more influence on beluga habitat selection in the spring. In ice-covered offshore regions, belugas may be engaged in under-ice and deep water foraging on Arctic cod (Boreogadus saida). In lighter ice years, belugas may expand their distribution and shift shoreward to take advantage of high prey densities along fast-ice edges. Both belugas and bowheads appeared to be feeding along the Franklin Bay ice edge in June 2008. More research is required to examine and compare possible changes in distribution since the late 1970s and to investigate the factors driving the patterns described.
Download or read book Seasonal Movement and Habitat Use of Beluga Whales in the Canadian Beaufort Sea written by Claire Hornby (Alexandra) and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Exploration of Grouping Characteristics and Spatial Distribution of Beluga Whales Delphinapterus Leucas in the Eastern Beaufort Sea written by Alexandra Mayette and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Beluga whales (Delphinapterus leucas) are considered social whales, but like any other cetaceans, the study of social behaviour is challenging to conduct. Due to the wide distribution of the Eastern Beaufort Sea beluga whale population across its summering grounds, little is known about the large-scale grouping behaviour and spatial distribution of groups. The aim of this research is to explore the grouping characteristics and organization of beluga groups, as well as the habitat preference of different social groups in summer. First, we used aerial photographs captured in July 2019 to describe group size, age composition, inter-individual distance, and swimming direction of beluga groups. We compared characteristics between two key summer habitats: the extended offshore of the Beaufort Sea shelf and the inshore of the Mackenzie Estuary. Results showed that group size and inter-individual distance were similar in both habitats. The average distance in a group varied with age composition and the swimming direction varied between the offshore and inshore. Second, we used GPS locations of beluga sightings recorded by visual observers during aerial surveys conducted in July and August 2019. We investigated the distribution of three beluga social group types (individual belugas, groups of adults, and groups with calf) using hierarchical generalized additive models. The sea surface temperature, bathymetry, and slope described best the summer distribution. Areas of high preference were often associated with prey distribution, suggesting foraging as the main driver of habitat preference. We also hypothesized that body size energy requirements contributed to the variation between the group types. This study revealed for the first-time observations of grouping behaviour in the summer habitat of the Eastern Beaufort Sea beluga whales. Although the results do not reflect the extent and complexity of beluga social behaviour, this study now provides an information baseline for this beluga population. We also encourage multidisciplinary research as an opportunity to further collect data and explore other elements of beluga whale sociality.
Download or read book Beluga Whale Distribution Migration and Behavior in a Changing Pacific Arctic written by Donna D. W. Hauser and published by . This book was released on 2016 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sea ice is disappearing at unprecedented rates in the Pacific Arctic with potential impacts to ice-associated marine predators that migrate to this seasonally accessible and productive ecosystem. In this dissertation I used satellite telemetry data spanning 1993-2012 collected from two migratory populations of beluga whales (Delphinapterus leucas) in the Pacific Arctic (i.e., Eastern Chukchi Sea and Eastern Beaufort Sea populations) to investigate how loss of sea ice and changes in other environmental factors affect distribution, movement, and behavior. I quantified fidelity to summer areas, sexual segregation, and migration timing as well as variations in diving behavior among regions. These analyses illustrate that population-scale patterns of philopatry, migration, and foraging are mediated by the combined effects of seasonal sea ice and oceanographic fluctuations, prey distribution, and social interactions. I also addressed the question of whether belugas would adjust their distribution, migration, and behavior to shifting sea ice conditions and to what extent matrilineally-learned behavior might supersede environmental forcing through the development of resource selection functions. Results indicate that sea ice is a contributing factor but not sole determinant of beluga habitat preferences. One population (Eastern Chukchi Sea) exhibits delayed fall migration in response to later sea ice freeze-up. Changing environmental conditions also seem to favor deeper, longer dives for this population. There were few overall differences in preferred habitat selection during 1990-2014, and summer distribution appears to be governed by philopatry rather than ice conditions. These results correspond to a conclusion that Eastern Chukchi Sea belugas are responding to a changing Pacific Arctic environment through behavioral plasticity in migration timing and foraging behavior. In contrast, there were few examples where migration timing or sea ice associations of Eastern Beaufort Sea belugas changed between the 1990s and 2000s. Taken as a whole, these results suggest population-specific responses by belugas in the face of fluctuating sea ice conditions. Across the circumpolar Arctic, some beluga populations may be more likely than others to adapt and persist in a changing climate.
Download or read book The Pacific Arctic Region written by Jacqueline M. Grebmeier and published by Springer. This book was released on 2014-06-10 with total page 461 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Pacific Arctic region is experiencing rapid sea ice retreat, seawater warming, ocean acidification and biological response. Physical and biogeochemical modeling indicates the potential for step-function changes to the overall marine ecosystem. This synthesis book was coordinated within the Pacific Arctic Group, a network of international partners working in the Pacific Arctic. Chapter topics range from atmospheric and physical sciences to chemical processing and biological response to changing environmental conditions. Physical and biogeochemical modeling results highlight the need for data collection and interdisciplinary modeling activities to track and forecast the changing ecosystem of the Pacific Arctic with climate change.
Download or read book Beluga Whale Habitat Selection and Distribution in the Mackenzie Estuary and the Tarium Niryutait Marine Protected Area written by Aurelie Noel and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Eastern Beaufort Sea (EBS) beluga population migrates to the Mackenzie Estuary and to the Tarium Niryutait Marine Protected Area every summer and the reasons behind this selection are not fully understood. Once in the Estuary, beluga whales (Delphinapterus leucas) are harvested by Inuvialuit communities of the Inuvialuit Settlement Region for whom they represent an essential country food, contributing to their well-being. In the last decade, community members voiced their concerns and identified research priorities pertaining to belugas resources, baselines and habitats. To enhance our understanding of EBS beluga whale habitat and further anticipate effects of a changing climate, it was crucial to understand why belugas select these habitats. We created a habitat model based on aerial surveys observations from the late summer 2019 paired with remote sensing imagery to establish a baseline of environmental and spatial conditions selected by belugas. Then we assessed the baseline against historical data. We finally evaluated the habitat model with concurrent tagged observations to integrate the inferences made at a larger spatio-temporal scale. High turbidity and warm water temperatures were the two most important factors explaining beluga presence and were associated with the inshore waters of the Mackenzie River channels and along unprotected coastlines. Comparisons with past observations suggested that the observed beluga distribution had shifted from the baseline and was probably the results of the influence of changing environmental conditions on beluga response, either on a temporary (i.e., acclimatisation) or permanent basis (i.e., adaptation). The evaluation of the habitat model showed mixed results. The inferences of selection, created in combining quality of environmental conditions and belugas mechanisms of selection, explained the intertwined patterns of beluga habitat distribution. Those findings enhanced our understanding of EBS beluga ecology and highlighted the complexity in defining and predicting beluga habitat distribution. This complexity, by preventing an accurate assessment of the changing beluga habitat distribution, represents new challenges for harvesters that who may have to switch the timing and location of their harvest in response.
Download or read book Study of Summer and Fall Movements and Dive Behaviour of Beaufort Sea Belugas Using Satellite Telemetry 1992 95 written by and published by . This book was released on 1997 with total page 39 pages. Available in PDF, EPUB and Kindle. Book excerpt: Describes project methods and presents highlights of results from a study of Beaufort Sea belugas, involving the tracking and recording of dive behaviour using satellite-linked time-depth recorders. Over four years of field and laboratory work and analysis, 14 males and six female belugas were live-captured and tagged in the Mackenzie River delta with satellite transmitters that were used to obtain detailed behavioural data to study migration routes to summer and winter concentration areas, to understand the effect of beluga movements and diving on population estimates based on aerial surveys, and to study habitat preferences and habitat use. Results showed unexpected behaviour on the part of Beaufort Sea belugas.
Download or read book Effects of Anthropogenic Noise on Animals written by Hans Slabbekoorn and published by Springer. This book was released on 2018-08-20 with total page 322 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the past several years, many investigators interested in the effects of man-made sounds on animals have come to realize that there is much to gain from studying the broader literature on hearing sound and the effects of sound as well as data from the effects on humans. It has also become clear that knowledge of the effects of sound on one group of animals (e.g., birds or frogs) can guide studies on other groups (e.g., marine mammals or fishes) and that a review of all such studies together would be very useful to get a better understanding of the general principles and underlying cochlear and cognitive mechanisms that explain damage, disturbance, and deterrence across taxa. The purpose of this volume, then, is to provide a comprehensive review of the effects of man-made sounds on animals, with the goal of fulfilling two major needs. First, it was thought to be important to bring together data on sound and bioacoustics that have implications across all taxa (including humans) so that such information is generally available to the community of scholars interested in the effects of sound. This is done in Chaps. 2-5. Second, in Chaps. 6-10, the volume brings together what is known about the effects of sound on diverse vertebrate taxa so that investigators with interests in specific groups can learn from the data and experimental approaches from other species. Put another way, having an overview of the similarities and discrepancies among various animal groups and insight into the “how and why” will benefit the overall conceptual understanding, applications in society, and all future research.
Download or read book Advances in Research on the Beluga Whale Delphinapterus Leucas written by Thomas G. Smith and published by . This book was released on 1990 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt: Collection of 14 articles representing a cross-section of current research on beluga whales, Delphinapterus leucas, in North American waters.
Download or read book Beaufort Sea Beluga Whales written by Lisa Lucia Loseto and published by . This book was released on 2007 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Mercury (Hg) levels in the Beaufort Sea beluga (Delphinapterus leucas) population have been increasing since the 1990's. Ultimately, it is the Hg content of prey that determines beluga Hg levels. However, the Beaufort Sea beluga diet is not understood, and little is known about the food webs and Hg sources in their summer habitat. Using satellite telemetry data, the Beaufort Sea Beluga were found to segregate into habitat use groups, by length, sex and reproductive status. Segregation of habitat use lead to the hypothesis that beluga may feed differently, explaining Hg dietary sources. Mercury levels were measured in three food webs in the western Canadian Arctic to assess their dietary Hg contribution. Results revealed that potential beluga prey had variable Hg concentrations. With the use of the diet biomarkers stable isotopes and fatty acids in both prey items and beluga, the beluga diet was evaluated by incorporating beluga biological variables such as age, length, sex and harvest location. Here, we show the factors driving beluga diet variability lead to differences in dietary Hg uptake. Diet variability within the Beaufort Sea beluga was evident, whereby larger beluga appeared to feed predominantly on offshore arctic cod (Boreogadus Saida), and medium and smaller sized beluga incorporated more near-shore fish collected from the Mackenzie shelf. The variation in beluga diet was supported by the differences in Hg concentrations and 815N values in both prey and beluga. For the first time, we demonstrate that food web Hg biomagnification processes drive beluga muscle Hg levels, rather than Hg bioaccumulation over time. This conclusion revealed that dietary Hg levels varied with habitat use, where the shelf was low source of Hg and the offshore was a high source. Therefor, incorporating beluga habitat use along with food web complexity was important in determining the factors driving beluga Hg levels. These observations lend support to the possibility that the high levels of Hg leaving the Mackenzie River only become bioavailability for food web uptake once entering offshore habitats"--Leaves [i]-ii.
Download or read book Beaufort Sea Beluga Whales written by Lisa Lucia Loseto and published by . This book was released on 2007 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Mercury (Hg) levels in the Beaufort Sea beluga (Delphinapterus leucas) population have been increasing since the 1990's. Ultimately, it is the Hg content of prey that determines beluga Hg levels. However, the Beaufort Sea beluga diet is not understood, and little is known about the food webs and Hg sources in their summer habitat. Using satellite telemetry data, the Beaufort Sea Beluga were found to segregate into habitat use groups, by length, sex and reproductive status. Segregation of habitat use lead to the hypothesis that beluga may feed differently, explaining Hg dietary sources. Mercury levels were measured in three food webs in the western Canadian Arctic to assess their dietary Hg contribution. Results revealed that potential beluga prey had variable Hg concentrations. With the use of the diet biomarkers stable isotopes and fatty acids in both prey items and beluga, the beluga diet was evaluated by incorporating beluga biological variables such as age, length, sex and harvest location. Here, we show the factors driving beluga diet variability lead to differences in dietary Hg uptake. Diet variability within the Beaufort Sea beluga was evident, whereby larger beluga appeared to feed predominantly on offshore arctic cod (Boreogadus Saida), and medium and smaller sized beluga incorporated more near-shore fish collected from the Mackenzie shelf. The variation in beluga diet was supported by the differences in Hg concentrations and 815N values in both prey and beluga. For the first time, we demonstrate that food web Hg biomagnification processes drive beluga muscle Hg levels, rather than Hg bioaccumulation over time. This conclusion revealed that dietary Hg levels varied with habitat use, where the shelf was low source of Hg and the offshore was a high source. Therefor, incorporating beluga habitat use along with food web complexity was important in determining the factors driving beluga Hg levels. These observations lend support to the possibility that the high levels of Hg leaving the Mackenzie River only become bioavailability for food web uptake once entering offshore habitats"--Leaves [i]-ii
Download or read book Beluga Habitats in the St Lawrence written by R. Michaud and published by . This book was released on 1990 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book For the Future of the Beluga written by Jacques Prescott and published by Sillery, Québec : Presses de l'Université du Québec. This book was released on 1990 with total page 382 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Le 29 septembre 1988, plus de 300 personnes envahissaient l'hôtel Tadoussac. Parmi ces participants se trouvaient quelque 30 chercheurs invités à faire le point sur l'état de la population des bélugas du Saint-Laurent, sa distribution dans l'estuaire, l'état de son habitat naturel et les impacts de la pollution de l'eau sur la santé de ces mammifères marins."--Page xvii.
Download or read book Sexual Segregation in Vertebrates written by Kathreen Ruckstuhl and published by Cambridge University Press. This book was released on 2005 with total page 512 pages. Available in PDF, EPUB and Kindle. Book excerpt: Males and females of many species can, and do, live separately for long periods of time. This sexual segregation is widespread and can be on social, spatial or habitat scales. An understanding of sexual segregation is important in the explanation of life history and social preference, population dynamics and the conservation of rare species. Sexual Segregation in Vertebrates explores the reasons why this behaviour has evolved and what factors contribute to it.
Download or read book Marine Fisheries Review written by and published by . This book was released on 1984 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Beluga Whales written by Anthony R. Martin and published by . This book was released on 2002 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dr Anthony Martin is a biologist and in this book he explores what we know about the beluga or white whale, and relates to the reader what research is currently being carried out on this species.
Download or read book Marine Mammals Ashore written by Joseph R. Geraci and published by National Aquarium in Baltimore. This book was released on 2005 with total page 386 pages. Available in PDF, EPUB and Kindle. Book excerpt: Comprehensive manual for understanding and carrying out marine mammal rescue activities for stranded seals, manatees, dolphins, whales, or sea otters.
