Download or read book Male Reproductive Success Relatedness and the Mating System of Weddell Seals in Mcmurdo Sound Antarctica written by Thomas Scott Gelatt and published by . This book was released on 2001 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Reproductive Strategies of Weddell Seals in McMurdo Sound Antarctica written by Ludivine Blandine Rousseau and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Phocid seals (true seals, Order Carnivora, Family Phocidae) use a diverse array of breeding habitats and strategies, and produce many vocalizations. Therefore, phocids are well suited as subjects for study of reproductive strategies and the role of vocalizations in species mating at sea. However, the amount of information is still limited for aquatically breeding pinnipeds. Using underwater audio and video recordings of Weddell seals (Leptonychotes weddellii) interacting in McMurdo Sound, I compared the frequencies of vocalizations and behaviors of males and females during the mating season. I also investigated differences in these frequencies based on the social context. Finally, I identified patterns of vocalizations and behaviors to help determine the behavioral context of calls and used this information as a basis for considering the degree of ritualization in Weddell seal displays. Mews, growls, knocks, and trills were found to be almost exclusively male-specific. The territorial male produced chirps more often when another male was present in its territory; whereas, mews and growls were more frequent when one or more free-ranging females were present. Several vocal and behavioral padeparture of the territorial male into or from the breathing hole. In the context of an evolutionary-based model of communication, these findings suggest that low-frequency vocalizations and stereotyped displays produced by territorial males may have been favored by sexual selection: they may provide reliable information to females about the fitness of the signaler and influence their choice of mate. They may also help in limiting conflicts between the territorial male and females over access to the breathing hole.
Download or read book Dynamics of a Weddell Seal Leptonychotes Weddellii Population in McMurdo Sound Antarctica written by Michael Foley Cameron and published by . This book was released on 2001 with total page 202 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Reproductive Ecology of Weddell Seals Leptonychotes Wedelli in McMurdo Sound Antarctica written by Susanne Elaine Braun Hill and published by . This book was released on 1985 with total page 106 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Sea Ice written by David N. Thomas and published by John Wiley & Sons. This book was released on 2008-04-15 with total page 419 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sea ice, which covers up to 7% of the planet’s surface, is a major component of the world’s oceans, partly driving ocean circulation and global climate patterns. It provides a habitat for a rich diversity of marine organisms, and is an extremely valuable source of information in studies of global climate change and the evolution of present day life forms. Increasingly sea ice is being used as a proxy for extraterrestrial ice covered systems. Sea Ice provides a comprehensive review of our current available knowledge of polar pack ice, the study of which is severely constrained by the logistic difficulties of working in such harsh and remote regions of the earth. The book’s editors, Drs Thomas and Dieckmann have drawn together an impressive group of international contributing authors, providing a well-edited and integrated volume, which will stand for many years as the standard work on the subject. Contents of the book include details of the growth, microstructure and properties of sea ice, large-scale variations in thickness and characteristics, its primary production, micro-and macrobiology, sea ice as a habitat for birds and mammals, sea ice biogeochemistry, particulate flux, and the distribution and significance of palaeo sea ice. Sea Ice is an essential purchase for oceanographers and marine scientists, environmental scientists, biologists, geochemists and geologists. All those involved in the study of global climate change will find this book to contain a wealth of important information. All libraries in universities and research establishments where these subjects are studied and taught will need multiple copies on their shelves. David Thomas is at the School of Ocean Sciences, University of Wales, Bangor, UK. Gerhard Dieckmann is at the Alfred Wegener Institute for Polar and Marine Research, Bremerhaven, Germany
Download or read book Exploring the relationship between parental relatedness and male reproductive success in the Antarctic fur seal Arctocephalus gazella written by J.I. HOFFMAN and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Weddell Seals written by Jeremy Schmidt and published by Weddell Seal Science. This book was released on 2023-10-06 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt: For more than 50 years, the Weddell Seal Science project has been studying the world’s southernmost breeding mammal in its farthest-south location, McMurdo Sound, on the ice-bound edge of Antarctica. This book explores the life history of Weddell seals — surprisingly approachable big-eyed, smiling-faced creatures — and details the science of studying them: the techniques, the motivations, the objectives, and the results. Although science is at the heart of the book, this is also an adventure story about scientists living in a remote field camp, far out on the sea ice, surrounded by glaciers, where you can feel the ocean pulsing beneath your feet. Seals are all around, penguins walk through camp, the weather can be exquisitely beautiful or too severe to step outside. Simply being there would be a wonderful experience on its own but in this case the objective is science — a deeper understanding of our endlessly fascinating planet.
Download or read book Reproductive Ecology of Weddell Seals Leptonychotes Weddell in McMurdo Sound Antaractica written by Suzanne Elaine Braun Hill and published by . This book was released on 1987 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Recruitment Probabilities and Reproductive Costs for Weddell Seals in Erebus Bay Antarctica written by Gillian Louise Hadley and published by . This book was released on 2006 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt: The study of life history traits such as age at first reproduction and the evaluation of recruitment probabilities and reproductive costs allow insight regarding the diverse factors and mechanisms shaping reproductive strategies. We investigated these mechanisms using a 26-year mark-resight dataset for Weddell seals (Leptonychotes weddellii) in Erebus Bay, Antarctica. Mean age at first reproduction was 7.62 years of age (SD=1.71), but varied from four to 14 suggesting the presence of important heterogeneity in quality among females. Survival rate was maximized for offspring of age-14 mothers (=0.70 [=0.08]), whereas recruitment probability was highest for pups born to youngest-breeding mothers. For example, probability of recruitment at age 7 was an average of 43% lower for seals born to age-14 mothers than for seals born to age-6 mothers. These results suggest the influence of countervailing selection (where favored genotypes for reproductive success are generally those that are selected against as juveniles). Sea-ice extent affected annual recruitment rates, likely due to cascading effects of oceanographic conditions on marine primary productivity and fluctuations in food availability for female Weddell seals. Results from the reproductive cost analysis strongly supported the presence of reproductive costs to survival (£p. SE£p. was 0.91 for breeders versus 0.94 for nonbreeders). Costs to fecundity were present for first-time breeders (mean probability of breeding the next year was 0.20 lower for first-time breeders than for experienced breeders). Females that delayed breeding until later in life experienced highest reproductive costs to fecundity, possibly due to their inferiority relative to other individuals in the population, again suggesting the influence of heterogeneity in individual quality. From these analyses we have gained insight into 1) the extent of within-population variation in important life-history characteristics for a long-lived species, and 2) the sources of this variation and potential linkages with environmental variables. Keys to future research will be 1) explaining variation in individual quality with random effects models or by using mass as an indicator variable, and 2) more detailed exploration of appropriate climate and sea-ice indices to elucidate linkages between this top trophic level predator and variation in the Antarctic marine environment.
Download or read book Dissertation Abstracts International written by and published by . This book was released on 2001 with total page 850 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Population Genetics and Mating System of Antarctic Fur Seals Arctocephalus Gazella at Livingston Island Antarctica written by Carolina Aimoré Bonin and published by . This book was released on 2012 with total page 139 pages. Available in PDF, EPUB and Kindle. Book excerpt: Antarctic fur seals, Arctocephalus gazella, were hunted to near-extinction in the early 1800's, but have recovered during the past 70 years to re-colonize most of their historical range. The large South Georgia (SG) fur seal population has been considered the main source of immigrants that re-colonized other areas, including Livingston Island (LI). Despite being one of the most exploited marine mammal species, clear evidence for a genetic bottleneck is lacking and instead, exceptionally high genetic diversity has been detected. Nevertheless, little is known about population-level patterns of genetic structure, or how this species' polygynous mating system may influence such patterns. This thesis fills some of this knowledge gap via extensive efforts in the field and in the laboratory, where over 1,000 individual samples were processed to obtain data on 17 highly polymorphic microsatellite markers; of these, 365 were also sequenced for mtDNA hypervariable region 1. The results of this work uncovered : (i) unexpected genetic differentiation between SG and LI indicating that LI was re-colonized by immigrants from one or more sources in addition to SG, (ii) remarkably high male reproductive success at a low-density LI colony during four breeding seasons, suggesting reduced competition among males at LI relative to the high-density colony of Bird Island (SG) (iii) a low percentage of rematings among individuals over the course of a decade, which was surprising considering the high level of breeding site fidelity and male reproductive skew found in this species, and (iv) one case of multiple-paternity in Antarctic fur seals among twins, showing that females may often escape control of territorial males within a breeding period. Not only do these findings provide unique insights into the remarkable re-colonization of Antarctic fur seals, but they also emphasize the importance of satellite populations for harboring genetic diversity through a period of profound anthropogenic disturbance. Additionally, by revealing complexities within male and female breeding behavior, this work advances our overall understanding of polygyny, providing insight into how it might function under different population densities and how individuals may interact over the course of their lives within this mating system.
Download or read book Canadian Journal of Zoology written by and published by . This book was released on 2004 with total page 742 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Long Term Patterns in Life History Characteristics and Population Dynamics of Weddell Seals Leptonychotes Weddelli in McMurdo Sound Antarctica written by J. Ward Testa and published by . This book was released on 1987 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt: The population dynamics of Weddell seals in McMurdo Sound, Antarctica, were studied between 1970 and 1984 using various methods. This thesis is a synthesis of the results of that research.
Download or read book Ecology of the Weddell seal in McMurdo Sound Antarctica written by I. STIRLING and published by . This book was released on 1969 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Evolution From Molecules to Men written by D. S. Bendall and published by CUP Archive. This book was released on 1983 with total page 612 pages. Available in PDF, EPUB and Kindle. Book excerpt: Giving a broad view of biological evolution the topics discussed here range from the history of the development of evolutionary thought, through current problems in molecular evolution and the evolution of whole organisms, to evolution of behaviour, sociobiology and man's place in evolution.
Download or read book American Doctoral Dissertations written by and published by . This book was released on 2000 with total page 816 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Population dynamics of Weddell seals Leptonychotes weddelli in McMurdo Sound Antarctica written by J.W. TESTA and published by . This book was released on 1987 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
