Download or read book An Assessment of Gray Whale Movements in Acoustically Changing Nearshore Environments written by Bruce R. Mate and published by . This book was released on 1999 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This grant helped fluid six field seasons over four years. The initial objective was to investigate the movements of gray whales in environments with varying levels of development and acoustic stimuli. The objective eventually broadened to identify the critical habitats of whales and investigate how natural variability and human activities affect the ways endangered whales utilize their environments. To accomplish these objectives, gray whales (1996) and humpbacks (1998) were tagged in Baja, blue whales were tagged along California (1998-99), and humpbacks were tagged around Hawaii (1998-99). The detailed route and rate of a gray whale's northbound migration was determined. Female gray whales with calves stayed in lagoons much longer than singular whales (x=22 days) suggesting the importance of these areas for development of newborn calves. We determined: Hawaiian humpbacks' movements in and around the winter reproductive grounds, various spring migration routes, new feeding areas, associations with oceanographic features, and movement patterns within the feeding grounds. Tagged blue whales were tracked during their feeding season off California, south along the Baja coast during their fall migration and to an upwelling area near the equator which is likely where some of the population goes to breed and calve.
Download or read book System Open Market Account written by and published by . This book was released on 1988 with total page 2 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Anthropogenic Disturbance of Western Gray Whale Behavior Off Sakhalin Island Russia written by Glenn Andrew Gailey and published by . This book was released on 2013 with total page 283 pages. Available in PDF, EPUB and Kindle. Book excerpt: The western North Pacific population of gray whales (Eschrichtius robustus) is critically endangered of extinction. The population size is estimated to be 131 individuals with 31 reproductive females. Throughout their potential home range, the western gray whale population face several threats to their future survival. On their only known feeding grounds off the northeastern coast of Sakhalin Island, Russia, anthropogenic activity has increased in the past decade due to oil and gas exploration and platform/pipeline construction. This dissertation examines the influences of geophysical seismic surveys (pulse sounds) and platform/pipeline installation (continuous sounds). Each chapter progressively improves upon behavioral models that assess changes in gray whale movements and respirations relative to anthropogenic activity. Theodolite tracking and focal follow methodologies were employed to collect gray whales' movement and respiration information during and in the absence of anthropogenic activity. Spatial, temporal, environmental, and acoustic (pulse and/or continuous) sound levels and non-sound related anthropogenic variables were included as explanatory variables to examine their influence on movement and respiration response variables, such as speed, orientations, dive/surface time, breathing rates, etc. During the 3-D seismic activity, gray whales traveled faster, changed directions of movement less, were recorded farther from shore and stayed underwater longer between respirations as the received sound level exposure increased. During platform/pipeline installations, western gray whales increased their distance from shore with indicators of stress (rapid breathing) and observed to be sensitive to close distance of approach by vessels. No acoustic influence on western gray whale behavior was found during a 4-D seismic survey; however, sample sizes were small in this study to sufficiently detect more subtle to moderate changes in gray whale behavior. These studies illustrate short-term influences anthropogenic activity had on western gray whale behavior which could lead to longer-term responses that may be detrimental to the survival of certain individuals and/or the population. A comprehensive analyses are proposed to increase sample sizes to identify subtle to moderate behavioral changes as well as examine alternative hypotheses to the null hypothesis of no impact used in this dissertation. With the potential to displace individuals/population out of critical feeding habitats needed for their annual survival and the expected increase of anthropogenic activity in the future, this dissertation highlights the importance to monitor and identify problems and suggest alternatives to development/activities that may be impacting this endangered population of gray whales. The electronic version of this dissertation is accessible from http://hdl.handle.net/1969.1/149559
Download or read book Gray Whale Monitoring Study written by and published by . This book was released on 1989 with total page 208 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Migrating Eastern North Pacific Gray Whale Behavior Compared Over Multiple Timescales written by Regina Anne Guazzo and published by . This book was released on 2018 with total page 165 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mysticetes (baleen whales) often make long, annual migrations from high latitude summer feeding areas to low latitude wintering areas. Eastern North Pacific gray whales (Eschrichtius robustus) migrate within a few kilometers from shore for most of their route from summer feeding areas in the Bering, Chukchi, and Beaufort Seas to wintering areas in the lagoons along the south-western coast of the Baja California Peninsula in Mexico. This dissertation combines passive acoustic recordings, infrared camera video, and visual sightings to investigate gray whale behavior and how it changes across different timescales. I use a four-element hydrophone array in central California to present the first published full-season acoustic monitoring and tracking of migrating gray whales. I describe the characteristics of calls produced by migrating gray whales and analyze how these characteristics change due to propagation. I show that gray whale behavior changes on diel and seasonal timescales. Notably, gray whales increase their vocalizations at night but their mean swimming behavior does not change, contrary to previous assumptions used in population size estimates. Over seasonal timescales, vocalizing gray whale swimming behavior aligns with previous observations. I explore how passive acoustic and infrared camera monitoring can help quantify whales by calculating cue rates or call and blow rates for migrating gray whales. Acoustic calling rates indicate that the gray whale population size is greater than estimated using visual sightings alone and that calling rate increases over the southbound migration. Infrared camera blow rates are less affected by whale behavior and are useful for daytime and nighttime monitoring, but are limited by visibility and distance. To understand gray whale behavior over seven migration seasons, I use visual daily counts at two sites and single-hydrophone call detections which indicate that migratory behavior seems to be driven more by intrinsic than the tested environmental factors. I find that the proportion of the population using a coastal route through the Southern California Bight, especially past Los Angeles, increased over these years. Understanding the behavior of migrating gray whales will help improve abundance estimates and determine how these whales may be impacted by nearshore anthropogenic activities and climate change.
Download or read book Documents concernant le film la Raison du coeur film Fran ais written by and published by . This book was released on with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Factors Influencing the Acoustic Behavior and Nearshore Residence of the Gray Whale Eschrichtius Robustus Along Their Migration Route written by and published by . This book was released on 2009 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: Our long-term goal is to quantify the acoustic behavior of gray whales in the coastal waters of the Northeast Pacific Ocean and to characterize the link between coastal residency patterns of these migratory mammals and the distribution of hyperbenthic swarms of their primary prey, mysids.
Download or read book Gray whale monitoring study written by and published by . This book was released on 1989 with total page 70 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book An Evaluation of Three Radio Tags Applied to Gray Whales and Their Utility in Assessing Whale Movements and Dive Characteristics written by Bruce R. Mate and published by . This book was released on 1991 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effects of Noise on Marine Mammals written by William John Richardson and published by . This book was released on 1991 with total page 488 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Gray Whale Eschrichtius Robustus written by Mary Lou Jones and published by Academic Press. This book was released on 2012-12-02 with total page 625 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Gray Whale: Eschrichtius robustus provides an introduction to the understanding of Eschrichtius robustus or the gray whale. This book explores the life processes, reproduction, and growth of large cetacean populations. Organized into four parts encompassing 25 chapters, this book begins with an overview of the gray whale evolution, fossils, and subfossil remains, range, and systematics in historical times. This text then presents the historical of gray whale exploitation and the economic importance of these whales to humans. Other chapters consider the gray whale migration, abundance, and seasonal distribution in the wake of the California population's recovery from depletion. This book discusses as well the methods used in shore-based censuses during migration and in aerial surveys of gray whales taken on their winter grounds. The final chapter deals with some innovative approaches to the study of free-ranging cetaceans. This book is a valuable resource for anthropologists, paleontologists, biologists, and naturalists.
Download or read book Hearing by Whales and Dolphins written by Whitlow W.L. Au and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 499 pages. Available in PDF, EPUB and Kindle. Book excerpt: Here, experts in different areas of the field provide an overview of the bioacoustics of whales and dolphins as well as a thorough introduction to the subject for investigators of hearing in other animals. Topics covered include the structure and function of cetacean auditory systems, the unique sound production system of odontocetes, acoustic communication, psychoacoustics, echolocation and models of sound propagation.
Download or read book Ocean Noise and Marine Mammals written by National Research Council and published by National Academies Press. This book was released on 2003-05-22 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt: For the 119 species of marine mammals, as well as for some other aquatic animals, sound is the primary means of learning about the environment and of communicating, navigating, and foraging. The possibility that human-generated noise could harm marine mammals or significantly interfere with their normal activities is an issue of increasing concern. Noise and its potential impacts have been regulated since the passage of the Marine Mammal Protection Act of 1972. Public awareness of the issue escalated in 1990s when researchers began using high-intensity sound to measure ocean climate changes. More recently, the stranding of beaked whales in proximity to Navy sonar use has again put the issue in the spotlight. Ocean Noise and Marine Mammals reviews sources of noise in the ocean environment, what is known of the responses of marine mammals to acoustic disturbance, and what models exist for describing ocean noise and marine mammal responses. Recommendations are made for future data gathering efforts, studies of marine mammal behavior and physiology, and modeling efforts necessary to determine what the long- and short-term impacts of ocean noise on marine mammals.
Download or read book Arctic Research of the United States written by and published by . This book was released on 2006 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Chukchi Sea Planning Area Oil and Gas Sale 193 and the Seismic Surveying Activities in the Chukchi Sea written by and published by . This book was released on 2007 with total page 372 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Passive Acoustic Monitoring of Cetaceans written by Walter M. X. Zimmer and published by Cambridge University Press. This book was released on 2011-04-21 with total page 367 pages. Available in PDF, EPUB and Kindle. Book excerpt: Passive acoustic monitoring is increasingly used by the scientific community to study, survey and census marine mammals, especially cetaceans, many of which are easier to hear than to see. PAM is also used to support efforts to mitigate potential negative effects of human activities such as ship traffic, military and civilian sonar and offshore exploration. Walter Zimmer provides an integrated approach to PAM, combining physical principles, discussion of technical tools and application-oriented concepts of operations. Additionally, relevant information and tools necessary to assess existing and future PAM systems are presented, with Matlab code used to generate figures and results so readers can reproduce data and modify code to analyse the impact of changes. This allows the principles to be studied whilst discovering potential difficulties and side effects. Aimed at graduate students and researchers, the book provides all information and tools necessary to gain a comprehensive understanding of this interdisciplinary subject.
Download or read book Mariana Islands Range Complex written by and published by . This book was released on 2010 with total page 612 pages. Available in PDF, EPUB and Kindle. Book excerpt:
