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Multimegameter-range acoustic data obtained by bottom mounted hydrophone arrays for measurement of ocean temperature
- IEEE J. of Ocean Engineering
, 1999
"... Abstract—Acoustic signals transmitted from the ATOC source on Pioneer Seamount off the coast of California have been received at various sites around the Pacific Basin since January 1996. We describe data obtained using bottom-mounted receivers, including U.S. Navy Sound Surveilance System arrays, a ..."
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Abstract—Acoustic signals transmitted from the ATOC source on Pioneer Seamount off the coast of California have been received at various sites around the Pacific Basin since January 1996. We describe data obtained using bottom-mounted receivers, including U.S. Navy Sound Surveilance System arrays, at ranges up to 5 Mm from the Pioneer Seamount source. Stable identifiable ray arrivals are observed in several cases, but some receiving arrays are not well suited to detecting the direct ray arrivals. At 5-Mm range, travel-time variations at tidal frequencies (about 50 ms peak to peak) agree well with predicted values, providing verification of the acoustic measurements as well as the tidal model. On the longest and northernmost acoustic paths, the time series of resolved ray travel times show an annual cycle peak-to-peak variation of about 1 s and other fluctuations caused by natural oceanic variability. An annual cycle is not evident in travel times from shorter acoustic paths in the eastern Pacific, though only one realization of the annual cycle is available. The low-pass-filtered travel times are estimated to an accuracy of about 10 ms. This travel-time uncertainty corresponds to errors in range- and depth-averaged temperature of only a few millidegrees, while the annual peak-to-peak variation in temperature averaged horizontally over the acoustic path and vertically over the upper 1 km of ocean is up to 0.5 C. Index Terms—Acoustic tomography, climate change. I.
The Conservation of British Cetaceans: A Review of the Threats and Protection Afforded to Whales, Dolphins and Porpoises in UK Waters
"... Cetaceans (whales, dolphins and porpoises) in UK and adjacent waters are being adversely affected by various human generated activities. The precise significance of virtually all of these is poorly known and this situation is made even worse because we also know little of the distributions and habit ..."
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Cetaceans (whales, dolphins and porpoises) in UK and adjacent waters are being adversely affected by various human generated activities. The precise significance of virtually all of these is poorly known and this situation is made even worse because we also know little of the distributions and habitat needs of these animals. In short, we may well be in danger in the seas of repeating the mistakes made earlier on land for many terrestrial species: driving them from their natural habitats, reducing ranges and depleting or even extinguishing populations. For marine animals the old adage of ‘out of sight and out of mind ’ still applies all too often and it is likely that the cumulative impact of human pressures is compromising the very survival of cetaceans around the UK. This review covers the established and emerging threats affecting cetaceans and makes a series of recommendations that should be urgently implemented if the policy makers in the UK really plan to meet their conservation commitments and save British whales and dolphins for future generations. Recommendations
Humpback Whale Song or Humpback Whale Sonar? A Reply to Au et al.
"... Abstract—Au and colleagues ’ arguments against the hypothesis that humpback whale songs function as long-range sonar are based on questionable assumptions rather than on empirical data. Like other echolocating mammals (e.g., bats), singing humpback whales: 1) localize targets in the absence of visua ..."
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Abstract—Au and colleagues ’ arguments against the hypothesis that humpback whale songs function as long-range sonar are based on questionable assumptions rather than on empirical data. Like other echolocating mammals (e.g., bats), singing humpback whales: 1) localize targets in the absence of visual information; 2) possess a highly innervated peripheral auditory system; and 3) modulate the temporal and spectral features of their sounds based on environmental conditions. The sonar equation is inadequate for determining whether humpback whale songs generate detectable echoes from other whales because it does not account for temporal variables that can strongly affect the detectability of echoes. In particular, the sonar equation ignores the fact that much of the noise encountered by singing humpback whales is spectrally and temporally predictable, and that audition in mammals is a dynamic and plastic process. Experiments are needed to test the hypothesis that singing humpback whales listen for and respond to echoes generated by their songs. Index Terms—Baleen whale, cetacean, environmentally-adaptive sonar, low-frequency sonar, mysticete.
TABLE OF CONTENTS TABLE OF CONTENTS............................................................................................................. 2 TERMS AND ABBREVIATIONS.....................................................................................
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Finding of No Significant Environmental Impact
"... turtle species. The proposed action area includes U.S. territorial waters and high seas of the ..."
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turtle species. The proposed action area includes U.S. territorial waters and high seas of the
TABLE OF CONTENTS TABLE OF CONTENTS............................................................................................................. 2 TABLE OF TABLES.............................................................................................
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North Pacific Right Whale Endangered No No No (Eubalaena japonica)
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Consultation by: Endangered Species Act Interagency Cooperation Division ofthe Office of Protected Resources, National Marine Fisheries Service Approved by:
, 2013
"... This biological opinion was prepared by NOAA's National Marine Fisheries Service (NMFS) Endangered ..."
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This biological opinion was prepared by NOAA's National Marine Fisheries Service (NMFS) Endangered
Revised 6/25/99 HUMPBACK WHALE (Megaptera novaeangliae): Central North Pacific Stock
"... The humpback whale is distributed worldwide in all ocean basins, though it is less common in Arctic waters. In winter, most humpback whales occur in the temperate and tropical waters of the North and South Hemispheres (from 10/-23/ latitude). Humpback whales in the North Pacific are seasonal migrant ..."
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The humpback whale is distributed worldwide in all ocean basins, though it is less common in Arctic waters. In winter, most humpback whales occur in the temperate and tropical waters of the North and South Hemispheres (from 10/-23/ latitude). Humpback whales in the North Pacific are seasonal migrants that feed on zooplankton and small schooling fishes in the cool, coastal waters of the
