Toward the Social and Acoustic Ecology of Social Foraging Humpback Whales (Megaptera Novaeangliae) in Southeast Alaska PDF Download

Author: Sean Frederick Thurman Hanser
Publisher:
ISBN:
Category :
Languages : en
Pages : 400

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Author: Fred Sharpe
Publisher:
ISBN:
Category : Humpback whale
Languages : en
Pages : 129

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Book Description
Relative to other baleen whale populations, the humpback whales Megaptera novaeangliae inhabiting Southeast Alaska are noteworthy in that they form large, enduring groups when foraging on schools of Pacific herring Clupea harengus pallasi. These groups use a variety of unusual feeding tactics when attacking prey, including the production of loud feeding calls, the release of bubbles, and the waving of their large pectoral flippers. Past observations of these groups have been largely anecdotal so little is known about their social behavior or the function of their feeding tactics. In particular, it is unclear if these pods are based on cooperative interactions or if they represent groups of individuals who are competing for prey that occurs in dense aggregations. In addition, little is known about the underlying social structure of these pods and whether they are composed of kin. The objective of this study was to employ field and laboratory techniques to gain insight into the function of the unusual feeding tactics, and to describe the basic social structure of these pods. In order to test the prediction that bubbles, feeding calls, and flipper movements represent prey manipulation tactics, herring schools were brought into the laboratory and subjected to various simulated humpback whale feeding behaviors. I found that these simulated behaviors produced strong avoidance responses from the herring schools, suggesting that humpback whales use these tactics to manipulate the behavior of their prey. Seven years of field observations revealed that humpbacks with enduring social bonds (i.e., high coefficients of association) specialized on herring and represented a small proportion of the entire whale population. Calves born to these "core members" were never observed to return and feed with their mothers in subsequent years, suggesting that these groups are not composed of close kin. This was verified by analysis of haplotype variation in the mitochondrial genome and microsatellite variation in the nuclear genome. Individuals within these pods appear to invest in by-product benefits, with the enduring bonds between whales in Chatham Strait (cf. krill feeders in Frederick Sound) possibly representing combinations of individuals performing compatible tasks (Le., bubble blower, herder, vocalizer).

Author: Andrew Szabo
Publisher:
ISBN:
Category : Humpback whale
Languages : en
Pages : 137

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The North Pacific humpback whale (Megaptera novaeangliae) population has been increasing at an average annual rate of ~6% since the early 1990s. In northern Southeast Alaska alone, there are now more whales than estimated for the entire North Pacific several decades ago. An understanding of how this growing population is repopulating traditional foraging grounds will benefit from detailed investigations of their prey preferences and trends in whale abundance and distribution relative to those prey. This dissertation examines these issues from late May until early September 2008 in Frederick Sound and Stephens Passage, a Southeast Alaskan feeding area historically used by humpback whales. The foundation for the study is an analysis of the life histories and abundance patterns of euphausiids, the principal prey of humpbacks in the area, during late spring and summer. Four species, Thysanoessa raschii, T. longipes, T. spinifera, and Euphausia pacifica, were identified in plankton net samples collected at random locations throughout the study site (n = 49) and in locations where a strong scattering layer was observed on a 120 kHz echosounder (n = 48). Both sample types varied in euphausiid species composition. Abundance patterns of immature euphausiids coupled with observations of females carrying spermatophores indicated differences between species in spawning schedules. Thysanoessa spp. began spawning in early April with the spring phytoplankton bloom and continued until late June, whereas E. pacifica began spawning in early June and continued until late August. This protracted recruitment of immature euphausiids was geographically widespread throughout the summer in contrast to adults, which, although present all summer, were found primarily in slope and shallow (

Author: Michelle Elizabeth Hardy Fournet
Publisher:
ISBN:
Category : Humpback whale
Languages : en
Pages : 110

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Humpback whales (Megaptera novaeangliae) are vocal baleen whales that exhibit complex social interactions that vary spatially and seasonally. Across their range, humpback whales produce a wide array of vocalizations including 'song', foraging vocalizations, and a range of vocalizations known as social calls -- unclassified non-song vocalizations. This study investigates the vocal repertoire and social calling behavior of Southeast Alaskan humpback whales from a sample of 299 vocalizations paired with 365 visual surveys collected over a three-month period on a foraging ground in Frederick Sound in Southeast Alaska. The results of this study describe a more varied and diverse repertoire of social vocalizations than has been previously documented, and identifies variability in vocal behavior as a function of social-spatial context. We used a three-part classification system that included aural-visual analysis, statistical cluster analyses, and discriminant function analysis to describe and classify social vocalizations. Vocalizations were classified into sixteen individual call types nested in seven vocal subclasses, within four vocal classes. The vocal repertoire of Southeast Alaskan humpbacks shows that call stereotypy ranges from discrete to continuous. This discrimination occurs at the vocal class and vocal subclass levels, and may be associated with call function. Social calls from Southeast Alaska showed anecdotal overlap with song from the 2012 North Pacific breeding season, and moderate overlap with vocalizations recorded in North Atlantic foraging grounds and along the East Australian migratory corridor. At the vocal class level aural-visual analysis had 83% agreement with cluster analysis and 90% agreement with discriminant function analysis. Results indicate that call use is not indiscriminant, and that some call types were commonly produced while others were rare. Moreover, calling rates in one vocal class, the pulsed (P) vocal class, were negatively correlated with mean nearest neighbor distance, indicating that P calling rates increased as animals clustered. This suggests the use of P calls may be spatially mediated. Results of a Poisson log linear (PLL) regression indicated that whale abundance in the survey area had no effect on vocal behavior; however, vocal behavior did vary significantly based on the spatial proximity of animals. The highest calling diversity occurred when whales were in clustered dispersion states, while the lowest calling diversity occurred when only a single whale was present. The type of calls produced during each dispersion state (clustered, random, evenly dispersed, single) varied significantly. While calls from all four vocal classes were detected during surveys containing clustered or randomly dispersed whales, calls from only two of the four classes were detected when whales were evenly distributed, and only one vocal class was detected from solitary whales. Our results indicated that vocal behavior is not correlated with abundance, that vocal behavior does vary based on social context, and that vocal behavior trends toward complexity as the potential for social interactions increases. Our evidence supports the hypothesis that social vocalizations serve a communicative purpose and may be used to maintain animal spatial proximity.

Author: Christopher W. Clark
Publisher: Springer Nature
ISBN: 3030984494
Category : Science
Languages : en
Pages : 390

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In this book, an international team of leading marine mammal scientists, with a remarkably diverse set of backgrounds and areas of expertise, lead you through a synthesis of current knowledge on baleen whales. Baleen whales are the largest animals ever to have lived on this planet. They also have the lowest and most intense voices on Earth, most likely evolved to take advantage of ocean acoustic transmission conditions so as to be detectable across ocean basins. Some baleen whales can live to be 150-200 years old. They migrate many thousands of kilometers between feeding and breeding areas. They produce songs and calls that serve as behavioral foundations for establishing, maintaining and expanding their cultural identities. To conclude that we know the behavioral limits of these large brained, long-lived animals would be naïve. As baleen whale scientists, we are still beginning to comprehend the enormous complexities and natural histories of these remarkable animals. Today, the fact that whales sing is known throughout much of the world. This awareness started 50 years ago with the publication and popularization of a collection of humpback song recordings that motivated research into baleen whale behavioral ethology. In this book’s chapters, a reader’s experiences will stretch from learning about baleen whale laryngeal anatomy associated with their different voices to learning about the vast ocean areas over which their voices can be heard and the emerging complexities of their culturally defined societies. These are accompanied by chapters on the fundamental ethological contexts of socializing, migrating, and foraging. Two common themes permeate the book. One theme highlights the phenomenal increase in scientific knowledge achieved through technological advancements. The other theme recognizes the impacts of human-made activities on ocean acoustic environments and the resultant influences on the health and survival of individual whales and their populations. Although the book is intentionally ambitious in its scope, as scientists, we fully recognize that baleen whale science is still in its infancy. Many profound revelations await discovery by cohorts of young, multi-talented explorers, some of whom are stretching their wings in this volume and some of whom are reading these scientific stories for the first time.

Author: Frederick A. Sharpe
Publisher: National Library of Canada = Bibliothèque nationale du Canada
ISBN: 9780612616790
Category : Humpback whale
Languages : en
Pages : 258

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Author: A. Rus Hoelzel
Publisher: John Wiley & Sons
ISBN: 1444311336
Category : Science
Languages : en
Pages : 448

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This book provides a general introduction to the biology of marine mammals, and an overview of the adaptations that have permitted mammals to succeed in the marine environment. Each chapter, written by experts in their field, will provide an up-to-date review and present the major discoveries and innovations in the field. Important technical advances such as satellite telemetry and time-depth-recorders will be described in boxes.

Author: David M. P. Jacoby
Publisher: Frontiers Media SA
ISBN: 2889747239
Category : Science
Languages : en
Pages : 186

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Author:
Publisher:
ISBN:
Category : Humpback whale
Languages : en
Pages : 2

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Author: John E. Reynolds
Publisher: Smithsonian Institution
ISBN: 1588344207
Category : Science
Languages : en
Pages : 589

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Book Description
Taking an integrated approach to the biology of marine carnivores, cetaceans, and sirenians, twenty-two prominent researchers compare marine mammals with one another and with terrestrial mammals, providing a framework for fundamental biological and ecological concepts. They describe functional morphology, sensory systems, energetics, reproduction, communication and cognition, behavior, distribution, population biology, and feeding ecology. They also detail the physiological adaptations—for such activities and processes as diving, thermo-regulation, osmoregulation, and orientation—that enable marine mammals to exploit their aquatic environment.