Killer Whales of Southern Alaska PDF Download

Author: Craig Matkin
Publisher:
ISBN: 9780963346797
Category : Whales
Languages : en
Pages : 96

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Author: Kenneth C. Balcomb
Publisher:
ISBN:
Category : Killer whale
Languages : en
Pages : 73

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Author: Daniel W. Olsen
Publisher:
ISBN:
Category : Killer whale
Languages : en
Pages : 150

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Book Description
The resident killer whale (Orcinus orca) is a genetically and behaviorally distinct ecotype of killer whale that feeds primarily on Pacific salmon (Oncorhynchus spp.). Long-term monitoring over 30 years of study has enabled detailed investigation into pod-specific, seasonal, and compositional differences in space use and behavior. To investigate use of habitat, 33 resident killer whales representing 14 pods in the northern Gulf of Alaska were tagged with satellite transmitters during all years from 2006 to 2014, and transmissions were received during the months of June to January. Core use areas were identified through utilization distributions using a biased Brownian Bridge movement model. Tagging results indicate different core use areas between pods, which could be due to cultural transmission within matrilineal groups. To investigate differences in behavior, 1337 hours of behavioral data were collected from 2006 to 2015. For these observations, chi squared tests were used to determine significant differences in behavior budgets between seasons, regions, haplotypes, and numbers of pods. The presence of 'rarely sighted' pods (sighted in less than 5% of encounters) had a large influence on the frequency of social behavior, which increased from 18.5% without their presence to 31.4% with it (X2 = 17.3, df = 1, P

Author: John K.B. Ford
Publisher: UBC Press
ISBN: 0774844329
Category : Nature
Languages : en
Pages : 98

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Book Description
This book focuses on transient killer whales. Enigmatic and elusive, these mammal-hunting whales are difficult animals to study. They travel in small groups, often moving unpredictably, which makes them less conspicuous than the larger resident pods. For these and other reasons, our understanding of the life history and ecology of transient killer whales has lagged behind that of residents. Transients contains the latest information on the natural history of transient killer whales, including their feeding habits, social lives, and distribution patterns. The catalogue section contains photographs of and notes on over 200 individual whales. Numerous sidebars contain interesting observations on encounters with transients as well as information on how and where to best watch them.

Author: Marilyn E. Dahlheim
Publisher: Seascape Research Alliance
ISBN:
Category : Nature
Languages : en
Pages : 238

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Author: John D. Hall
Publisher:
ISBN:
Category : Killer whale
Languages : en
Pages : 96

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Author: Hubbs-Sea World Research Institute
Publisher:
ISBN:
Category : Killer whale
Languages : en
Pages :

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Author: Stephen Leatherwood
Publisher:
ISBN:
Category : Killer whale
Languages : en
Pages : 59

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Book Description

Author: Stephen Leatherwood
Publisher:
ISBN:
Category : Killer whale
Languages : en
Pages : 10

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Book Description

Author:
Publisher:
ISBN:
Category : Killer whale
Languages : en
Pages : 0

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Book Description
The widespread loss of apex consumers in marine, terrestrial, and freshwater ecosystems throughout the world has precipitated profound trophic cascades and switches to different ecological states. However, conserving top predators can deliver broad biodiversity benefits and improve ecosystem resiliency. Effective conservation and management policy is predicated on a species’ distribution and abundance in a given area and time. In this dissertation, I provide new insight into killer whale (Orcinus orca) distribution, vocal behavior, and abundance in the Gulf of Alaska using passive acoustic monitoring and advance long-term monitoring capacity for this species. First, I describe the year-round spatiotemporal distribution and daily acoustic residency patterns of southern Alaska resident (fish-eating) and two populations of transient (mammal-eating) killer whales. I found distinct seasonal patterns across locations for each genetically distinct population and discovered that both resident and transient killer whales used the coastal monitoring areas more extensively than previously known—including in winter. Second, I estimated resident and transient killer whale calling rates, a prerequisite to acoustic abundance estimation. I found that the mean calling rate for southern Alaska resident (fish-eating) killer whales was consistent across space, time, ambient noise level, which pod was calling, and the presence of other pods. Gulf of Alaska transient (mammal-eating) killer whale calling rates were higher than resident’s and differed across locations. AT1 transients (mammal-eating) produced fewer calls more rapidly than Gulf of Alaska transients, and their mean rate was stable across spatiotemporal factors. Although transients call less often than residents, I found that once vocalizing, they do so at a higher rate. Finally, I estimated and modeled the year-round daily acoustic abundance of resident and transient killer whales across distinct areas in the Gulf of Alaska and developed Bayesian time series models to describe seasonal patterns and predict future abundance. Acoustic abundance estimates for the southern Alaska resident and Gulf of Alaska transient killer whales matched expectations from visual studies. I established distinct seasonal abundance patterns across areas, and acoustic monitoring enabled killer whale abundance estimation across a greater spatiotemporal extent than other methods. This work is critical for an accurate understanding of killer whales’ top-down forcing effects in the marine ecosystem, as well as to inform conservation and management policy for this federally protected species.