Download or read book Abundance and Distribution of Arctic Cod Boreogadus Saida in the Southeastern Beaufort Sea written by Canadian Atlantic Fisheries Scientific Advisory Committee and published by . This book was released on 1979 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Abundance and Distribution of Arctic Cod Boreogadus Saida in the Southeastern Beaufort Sea written by Canadian Atlantic Fisheries Scientific Advisory Committee and published by . This book was released on 1979 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Spatial Patterns Environmental Correlates and Potential Seasonal Migration Triangle of Arctic Cod Boreogadus Saida Distribution in the Chukchi and Beaufort Seas written by Caitlin Forster and published by . This book was released on 2019 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt: Arctic Cod (Boreogadus saida) is a key forage fish species in the Arctic marine ecosystem and provides a critical energetic link between lower and upper trophic levels. Despite its ecological importance, spatially explicit studies synthesizing Arctic Cod distribution across a multitude of research efforts previously have not been conducted in the western portion of its range. I used spatial generalized additive models (GAM) to map the distribution of Arctic Cod by size class and relative to environmental variables. I compiled demersal trawl data from 21 research cruises conducted from 2004 to 2017 in the Chukchi and Beaufort seas, and investigated size-specific patterns in distribution to infer movement ecology of Arctic Cod as it develops from juvenile to adult life stages. High abundances of small, juvenile Arctic Cod (70 mm total length) in the northeastern Chukchi Sea and western Beaufort Sea were separated from another region of high abundances in the eastern Beaufort Sea, near the US and Canadian border, suggesting possible population structure in the Pacific Arctic. In both the Chukchi and Beaufort seas, large, adult Arctic Cod (130 mm total length) were found offshore and spatially segregated from small and medium (71–130 mm total length) fish, indicating an ontogenetic offshore movement of Arctic Cod as it matures. Relating environmental correlates to Arctic Cod abundance demonstrated that temperature and salinity were related to juvenile distribution patterns, while depth was the primary correlate of adult distribution. Furthermore, a comparison of spring and summer 2017 abundances of Arctic Cod in the southern Chukchi Sea, from the Bering Strait to Cape Lisburne found low abundance in the spring when compared to the summer. Differences in Arctic Cod abundance at different times of year suggest that Arctic Cod migrate seasonally, potentially following patterns of biological production in the Chukchi Sea. Arctic Cod migration may follow a classical ‘migration triangle’ route between nursery grounds as juveniles, feeding grounds as subadults, and spawning grounds as adults, in relation to ice cover and seasonal production in the Chukchi Sea. The analysis presented here is necessary to address federally mandated research requirements, which include improving understanding of stock structure and resolving essential fish habitat (EFH) for different life stages, as well as to gain better general understanding of the role of Arctic Cod in the Pacific Arctic.

Download or read book Age Growth and Movement Dynamics of Arctic Cod Boreogadus Saida in the Chukchi and Beaufort Seas written by Alyssa Frothingham and published by . This book was released on 2020 with total page 166 pages. Available in PDF, EPUB and Kindle. Book excerpt: Arctic Cod (Boreogadus saida) dominates fish assemblages in the Arctic and provides a valuable food source to upper trophic level predators. Little is known about several important facets of its biology and ecology in the Pacific Arctic, including in the Chukchi and Beaufort seas. The physical connectivity of these two biologically and hydrologically unique seas provides an excellent opportunity to explore differences in Arctic Cod life history characteristics such as age, growth, and movement dynamics in these two adjacent areas. To establish a current benchmark of Arctic Cod life history and movement characteristics for the Pacific Arctic, Arctic Cod otoliths collected from 2009 to 2014 during twelve research cruises conducted throughout the Chukchi and Beaufort seas were used to estimate growth and age structure for this species from the two regions. Ages of Arctic Cod ranged from 0 to 5 years with significant overlap in size at age. Growth of Arctic Cod collected in the southern Chukchi Sea and eastern Beaufort Sea regions were similar, suggesting freshwater-influenced regions may enhance growth compared to other areas. Additionally, microchemistry of age-0 Arctic Cod otoliths was analyzed to determine potential differences in elemental signatures between the Chukchi and Beaufort seas, and to infer movement between them. Otolith trace element concentrations were distinct between the Chukchi and Beaufort seas, indicating populations of Arctic Cod from the Chukchi and Beaufort seas can be differentiated based on otolith elemental signatures. Furthermore, elemental signatures from the cores of otoliths were significantly different from those from the edges in both seas suggesting early life history movement. As the Pacific Arctic faces warming sea temperatures and sea ice reduction, predicting a species-level adaptation to a changing environment is nearly impossible without establishing a benchmark for future comparison. This research will provide valuable insight into Arctic Cod across a broad portion of its distribution.

Download or read book Diets Distribution and Population Dynamics of Arctic Cod Boreogadus Saida in Arctic Shelf Ecosystems written by Jennifer Marie Marsh and published by . This book was released on 2019 with total page 306 pages. Available in PDF, EPUB and Kindle. Book excerpt: With climate warming and longer open-water seasons in the Arctic, there is an increased interest in shipping, oil exploration and the expansion or development of commercial fisheries. Anticipated natural and anthropogenic changes are expected to alter the Arctic shelf ecosystems, including their fish communities. As a component of the Arctic Ecosystem Integrated Survey (Arctic Eis), this project presented a unique opportunity to assess the ontogenetic, spatial and temporal variability in the distribution, abundance and trophic roles (trophic level and diet sources) of key fish species in the Chukchi Sea. For my dissertation, I addressed three objectives to advance our understanding of Arctic cod (Boreogadus saida) as a key component of Arctic ecosystems. First, I characterized the current range of variability in trophic roles within the system and explored the role of advection in shaping the fish communities’ diet (isotopic signatures) with a focus on Arctic cod. Second, I examined environmental and biological influences on the distribution and abundance of Arctic cod and provided an updated stock assessment for the Chukchi Sea. Finally, I broadened the geographic scope and used available time series of survey data at the southern margin of their range in the Pacific (eastern Bering Sea) and Atlantic (Newfoundland/Labrador shelves) sectors to assess the influence of temperature, predators and competitors on their distribution. Compared to age-1+ Arctic cod, age-0 Arctic cod had a less diverse diet regardless of water mass and were limited to colder temperatures. Together, this suggests that younger Arctic cod are more vulnerable to climate change. Estimates of egg production and early survival suggest that the numbers of mature Arctic cod present in the survey area during summer are unlikely to produce the observed high abundances of age-0 Arctic cod in the Chukchi Sea. Moreover, Arctic cod distributions in their southern ranges were highly influenced by temperature and to a lesser extent by competitors and predators. When temperatures were warmer, Arctic cod occupied a smaller area. These results inform the management of Arctic cod in a rapidly changing environment and provide benchmarks against which to assess future changes.

Download or read book Sex and Age Dependent Differences and Habitat Influences on Demersal Arctic Cod Boreogadus Saida Lepechin 1774 Diet and Energy Allocation in the Canadian Beaufort Sea written by Brittany Lynn and published by . This book was released on 2016 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Arctic Cod, Boreogadus saida (Lepechin 1774) occur throughout the circumpolar north at all levels of the water column depending on their life history stage, the time of day, the season, and their activity. Arctic Cod are the most abundant fish species in the Canadian Beaufort Sea (CBS) ecosystem, and are an important link in the flow of energy within the food web. This study examined differences in energy acquisition and usage in Arctic Cod among three depth zones in the CBS (from 15-800m) by examining stomach contents and physiological indicators, taking into account sex, age and body size. Nonparametric comparison analyses found no differences with depth, but support for an ontogenetic shift in diet regarding prey size, a difference in energy content of an average diet between size classes 1 (30-60mm) and 2-4 (2: 60-90mm; 3: 90-120mm; 4: >120mm), and a slight positive relationship between physiological indicators and body size.

Download or read book Special Report written by and published by . This book was released on 1993 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Arctic Ecology written by David N. Thomas and published by John Wiley & Sons. This book was released on 2021-01-26 with total page 468 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Arctic is often portrayed as being isolated, but the reality is that the connectivity with the rest of the planet is huge, be it through weather patterns, global ocean circulation, and large-scale migration patterns to name but a few. There is a huge amount of public interest in the ‘changing Arctic’, especially in terms of the rapid changes taking place in ecosystems and exploitation of resources. There can be no doubt that the Arctic is at the forefront of the international environmental science agenda, both from a scientific aspect, and also from a policy/environmental management perspective. This book aims to stimulate a wide audience to think about the Arctic by highlighting the remarkable breadth of what it means to study its ecology. Arctic Ecology seeks to systematically introduce the diverse array of ecologies within the Arctic region. As the Arctic rapidly changes, understanding the fundamental ecology underpinning the Arctic is paramount to understanding the consequences of what such change will inevitably bring about. Arctic Ecology is designed to provide graduate students of environmental science, ecology and climate change with a source where Arctic ecology is addressed specifically, with issues due to climate change clearly discussed. It will also be of use to policy-makers, researchers and international agencies who are focusing on ecological issues and effects of global climate change in the Arctic. About the Editor David N. Thomas is Professor of Arctic Ecosystem Research in the Faculty of Biological and Environmental Sciences, University of Helsinki. Previously he spent 24 years in the School of Ocean Sciences, Bangor University, Wales. He studies marine systems, with a particular emphasis on sea ice and land-coast interactions in the Arctic and Southern Oceans as well as the Baltic Sea. He also edited a related book: Sea Ice, 3rd Edition (2017), which is also published by Wiley-Blackwell.

Download or read book Beaufort Environmental Monitoring Project 1983 1984 written by Northern Affairs Program (Canada) and published by Canadian Museum of Civilization/Musee Canadien Des Civilisations. This book was released on 1985 with total page 374 pages. Available in PDF, EPUB and Kindle. Book excerpt: The research and monitoring program recommended by this projectis structured around a set of hypothesized environmental impacts. For each of these nineteen hypotheses, the report diagrams anddetails the environmental linkages that need to be examined, describes how work should proceed and provides references on thetopic. The project draws conclusions as to the validity, testability and likelihood of each of the hypothesized effects.

Download or read book Aspects of the biology of Arctic cod Boreogadus saida and its importance in Arctic marine food chains written by M.S.W. Bradstreet and published by . This book was released on 1986 with total page 193 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Arctic written by and published by . This book was released on 1983 with total page 450 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Beaufort Sea Coastal Fish Studies written by Robert K. Harris and published by . This book was released on 1993 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Alaska Outer Continental Shelf Seismic Surveys in the Beaufort and Chukchi Seas written by and published by . This book was released on 2007 with total page 468 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book FAO Species Catalogue written by Daniel M. Cohen and published by . This book was released on 1990 with total page 460 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Mechanics and Physiology of Animal Swimming written by L. Maddock and published by Cambridge University Press. This book was released on 1994-09-15 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume brings together current research on a wide range of swimming organisms, with an emphasis on the biomechanics, physiology and hydrodynamics of swimming in or on water. Several chapters deal with different aspects of fish swimming, from the use of different 'gaits' to the operation of the locomotor muscles. All chapters are by recognised authorities in their different fields, and all are accessible to biologists interested in aquatic locomotion.

Download or read book Fish and Shellfish written by Rasmus Nielsen and published by Nordic Council of Ministers. This book was released on 1994 with total page 280 pages. Available in PDF, EPUB and Kindle. Book excerpt:

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.