Anthropogenic Disturbance of Western Gray Whale Behavior Off Sakhalin Island, Russia
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 th...
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fttexasamuniv:oai:oaktrust.library.tamu.edu:1969.1/149559 2023-07-16T04:00:43+02:00 Anthropogenic Disturbance of Western Gray Whale Behavior Off Sakhalin Island, Russia Gailey, Glenn Andrew Würsig, Bernd Davis, Randall Marshall, Christopher Rowe, Gilbert 2013-10-03T15:09:00Z application/pdf https://hdl.handle.net/1969.1/149559 en eng https://hdl.handle.net/1969.1/149559 Gray Whales Movement Respirations Seismic Anthropocentric Activity Disturbance Thesis text 2013 fttexasamuniv 2023-06-27T22:29:14Z 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 ... Thesis Sakhalin Texas A&M University Digital Repository Pacific |
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Texas A&M University Digital Repository |
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fttexasamuniv |
language |
English |
topic |
Gray Whales Movement Respirations Seismic Anthropocentric Activity Disturbance |
spellingShingle |
Gray Whales Movement Respirations Seismic Anthropocentric Activity Disturbance Gailey, Glenn Andrew Anthropogenic Disturbance of Western Gray Whale Behavior Off Sakhalin Island, Russia |
topic_facet |
Gray Whales Movement Respirations Seismic Anthropocentric Activity Disturbance |
description |
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 ... |
author2 |
Würsig, Bernd Davis, Randall Marshall, Christopher Rowe, Gilbert |
format |
Thesis |
author |
Gailey, Glenn Andrew |
author_facet |
Gailey, Glenn Andrew |
author_sort |
Gailey, Glenn Andrew |
title |
Anthropogenic Disturbance of Western Gray Whale Behavior Off Sakhalin Island, Russia |
title_short |
Anthropogenic Disturbance of Western Gray Whale Behavior Off Sakhalin Island, Russia |
title_full |
Anthropogenic Disturbance of Western Gray Whale Behavior Off Sakhalin Island, Russia |
title_fullStr |
Anthropogenic Disturbance of Western Gray Whale Behavior Off Sakhalin Island, Russia |
title_full_unstemmed |
Anthropogenic Disturbance of Western Gray Whale Behavior Off Sakhalin Island, Russia |
title_sort |
anthropogenic disturbance of western gray whale behavior off sakhalin island, russia |
publishDate |
2013 |
url |
https://hdl.handle.net/1969.1/149559 |
geographic |
Pacific |
geographic_facet |
Pacific |
genre |
Sakhalin |
genre_facet |
Sakhalin |
op_relation |
https://hdl.handle.net/1969.1/149559 |
_version_ |
1771549794805743616 |