Download or read book Estimation of Abundance of Blue Whale Calls Off Central California Using a Seafloor mounted Hydrophone written by Anurag Kumar and published by . This book was released on 2003 with total page 102 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Estimating Whale Abundance Using Sparse Hydrophone Arrays written by Danielle V. Harris and published by . This book was released on 2012 with total page 331 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Blue Whale Acoustic Behavior Off Southern California written by Leah Allison Lewis and published by . This book was released on 2017 with total page 97 pages. Available in PDF, EPUB and Kindle. Book excerpt: The acoustic repertoire of the Northeast Pacific population of blue whales (Balaenoptera musculus) consists of three different sounds: A, B, and D calls. The pulsed A and tonal B calls can be produced singularly or in phrases or songs, while downswept D calls are only produced as singular calls. Although these sounds have been well described, the behavioral context of sound production is poorly understood. To investigate spatial and temporal variability in blue whale call and song usage off southern California, passive acoustic data collected from four High-Frequency Acoustic Recording Packages (HARPs) were analyzed. The acoustic and dive profile data collected through tags deployed on blue whales were also analyzed to describe the behavioral context of sound production. Singular call and phrase production rates were calculated to assess variability in sound type abundances on different spatial, temporal and behavioral scales. Distinct differences in song type preference were apparent, with offshore sites featuring songs comprised of multiple sequential B units following a single A, while inshore, A and B units alternated. Most blue whale sounds were produced during the summer and fall. The majority of all sounds produced by tagged blue whales occurred during non-lunging dives at shallow depths (less than 30 m). Song production was associated with shallow, non-lunging dives, while singular calls often occurred during lunging dives or bouts of surface behavior. The observed differences in blue whale acoustic behavior off southern California will aid in the development of context specific rates for future models of density estimation.

Download or read book Numbers of Calling Whales in the North Pacific written by William A. Watkins and published by . This book was released on 2001 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since November 1995, the U.S. Navy's Sound Surveillance System (SOSUS) and other hydrophone arrays were used to regularly sample the occurrence of whale sounds in four regions bordering the continental margins across the North Pacific. The numbers of whales heard calling varied with season and location for each species, blue whales (Balaenoptera musculus), fin whales (Balaenoptera physalus), and humpback whales (Megaptera novaeangliae). For blue whales, calling during the fall season averaged 5 whales per event, winter averaged 1.5 whales per event, spring averaged 1 whale, and summer averaged 1.5 whales. For fin whales the numbers of whales heard ('F' calls from individuals) during winter averaged 3 whales per event, spring and fall calling averaged 1.5 whales, and summer averaged 1 whale. The 'J' calling events, regardless of season, were judged to be from at least 6 fin whales. Humpback singing typically was from 3 whales. These number demonstrated seasonal variations in calling whales for each region.

Download or read book Characterization of Blue Whale Calls from the Northeast Pacific and Development of a Matched Filter to Locate Blue Whales on the U S Navy SOSUS SOund SUrveillance System Arrays written by Kathleen Mary Stafford and published by . This book was released on 1995 with total page 158 pages. Available in PDF, EPUB and Kindle. Book excerpt: Blue whales (Balaenoptera musculus) are the largest of the baleen whales. Blue whale calls were recorded off the coast of California in fall, 1993 and measured for frequency and time characteristics. On average, blue whale calls lasted 16 s, swept down from 18.9 to 17.3 Hz and were repeated every 38 s. These results are similar to blue whale calls recorded elsewhere in that they possess a frequency downsweep component which lasts from 16-18 s. Ambient noise levels in the ocean due to sources such as wind, waves or shipping can make it difficult to detect blue whale calls in raw hydrophone data. The characteristics of the blue whale calls recorded in the field were sufficiently similar to design a matched filter (kernel) to automatically detect calls obscured by ambient noise. This filter worked well at identifying blue whale calls when applied to the data from which it was derived and on data from the U.S. Navy's SOSUS (SOund SUrveillance System) array. The U.S. Navy has been monitoring low-frequency sounds in the northeast Pacific using bottom-mounted hydrophone arrays since the mid- 1950's. The use of this system was extended to the study of low-frequency whale calls. By applying the matched filter developed from field data to each of three hydrophone arrays and using location algorithms developed for seismic work, it was possible to pick the same call on each array and determine its location by examining the arrival time differences at each hydrophone and comparing this to a predefined location. To confirm the validity of these locations, a ground-truthing experiment was conducted whereby a Navy P-3 aircraft was given locations determined with the matched filter to try to visually and/or acoustically locate blue whales off the Oregon coast. Other locations were determined for 10 days in July and August, 1994.

Download or read book Calling Behavior of Blue and Fin Whales Off California written by Erin Marie Oleson and published by . This book was released on 2005 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Estimation of the Source Signal Characteristics and Variability of Blue Whale Calls Using a Towed Array written by Therese C. Moore and published by . This book was released on 1999 with total page 59 pages. Available in PDF, EPUB and Kindle. Book excerpt: A four-day experiment was conducted to study the feasibility of locating, tracking, and counting blue whales acoustically in the Monterey Bay National Marine Sanctuary (MBNMS) at long ranges using the shore-based NPS Ocean Acoustic Observatory (OAO) hydrophone array. In concert with the shore-based acoustic monitoring, an aircraft was assigned to locate whales and a research vessel was manned with observers and instrumented with a towed hydrophone array to determine whale locations and characterize their vocalizations in the near-field. Two transiting blue whales were observed and their vocalizations were recorded by the towed array in close proximity. In this thesis research, these towed array data were deverberated using modeled-based matched signal processing and least-squares fitting.

Download or read book Master s Theses Directories written by and published by . This book was released on 2004 with total page 324 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Education, arts and social sciences, natural and technical sciences in the United States and Canada".

Download or read book Estimation of the Source Signal Characteristics and Variability of Blue Whale Calls Using a Towed Array written by and published by . This book was released on 1999 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: A four-day experiment was conducted to study the feasibility of locating, tracking, and counting blue whales acoustically in the Monterey Bay National Marine Sanctuary (MBNMS) at long ranges using the shore-based NPS Ocean Acoustic Observatory (OAO) hydrophone array. In concert with the shore-based acoustic monitoring, an aircraft was assigned to locate whales and a research vessel was manned with observers and instrumented with a towed hydrophone array to determine whale locations and characterize their vocalizations in the near-field. Two transiting blue whales were observed and their vocalizations were recorded by the towed array in close proximity. In this thesis research, these towed array data were deverberated using modeled-based matched signal processing and least-squares fitting.

Download or read book Blue and Fin Whale Acoustics and Ecology Off Antarctic Peninsula written by Ana Širović and published by . This book was released on 2006 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Blue whales (Balaenoptera musculus) and fin whales (B. physalus) in the Southern Ocean were subjects of extensive whaling industry during the twentieth century. Their current population numbers remain low, making population monitoring using traditional visual surveys difficult. Both blue and fin whales produce low frequency, regularly repeated calls and are suitable for acoustic monitoring. Eight continuously recording acoustic recorders were deployed off the Western Antarctic Peninsula (WAP) between March 2001 and February 2003. Ranges to calling blue and fin whales were calculated using hyperbolic localization and multipath arrivals up to the distances of 200 and 56 km., respectively. Calls of both species had high intensity, blue whales calls had the average source level 189±3dB re: 1[mu]Pa at 1 meter and the average fin whale call source level was 189±4dB re: 1[mu]Pa at 1 meter. Automatic call detection methods were used for analysis of calling blue and fin whale seasonal presence and habitat preferences. Blue whale calls were detected year round (on average 177 days/year) with peak calling in March and April and a secondary peak in October and November. Fin whale calling rates were seasonal with calls detected between February and June (on average 51 days/year) with a peak in May. During the entire deployment period, detected calls from both species showed negative correlation with sea ice concentrations. Baleen whale sounds were recorded during multiple cruises off the Antarctic Peninsula using sonobuoys. Recordings from two fall cruises off the WAP were used for analyses of habitat preferences of calling blue and fin whales. The presence of calling blue whales was positively correlated with bottom depth and sea surface temperature and negatively correlated with krill biomass in the top 100 meters and abundance of the rest of the zooplankton at depth (101-300 meters). Locations of fin whale calls were associated with a deep trough area and high Chl-a concentrations. Distribution of baleen whale calls recorded in the Scotia Sea (east of the Antarctic Peninsula) indicated that fin whales occur in open water, and blue, southern right (Eubalaena australis), minke (B. bonaerensis), and humpback whales (Megaptera novaeangliae) occur near islands or close to the ice edge.

Download or read book Blue Whale Ecology and Behavior in a Human impacted Marine Ecosystem written by Angela Renee Szesciorka and published by . This book was released on 2021 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt: To avoid missing peak prey abundances, blue whales must detect available environmental cues and time migration by shifting arrival or departure dates to/from feeding grounds and balancing the time they spend foraging versus breeding. Blue whale feeding habitat overlaps with dense vessel traffic, making them vulnerable to vessel strikes--the leading cause of human mortality for blue whales off Southern California. Any changes to migration timing that increase residence time on the feeding grounds may increase vessel strike risk. The contextual factors influencing vessel strike risk are poorly understood and uncertainty remains about whale behavioral response to vessels. Understanding those interactions is important in preventing vessel strikes. Here, I investigated the timing and drivers of blue whale migration and blue whale-vessel interactions using seafloor- and animal-mounted acoustic devices. This allowed me to (a) examine the relationship among migration timing (inferred from blue whale "D" and "B" calls), environmental indices (e.g., sea surface temperature anomalies), and prey (spring krill biomass from annual net tow surveys) during a 10 year period (2008-2017) off Southern California and (b) assess vessel, environmental, and whale contextual variables associated with 216 close passages (2 km) between 174 vessels and 35 tagged whales and look for differences and uniqueness in dive behavior resulting from close passages. Colder sea surface temperature anomalies the previous season were correlated with greater krill biomass the following year, and earlier arrival by blue whales, demonstrating a plastic response of whales to interannual variability and the importance of krill as a driving force behind migration timing. By the end of the 10-year period, whales were arriving at the feeding grounds more than one month earlier, suggesting climate change has led to blue whales extending their overall time in Southern California. None of the contextual variables showed any relationship with close passage distance with vessels. Whales did not leave the area, even when passages were chronic (5/day), and we found no evidence of behavioral response. With no evidence of behavioral responses to close vessel passages, we need to continue managing vessel traffic under the assumption that whales do not avoid vessels.

Download or read book Photographic Identification and Abundance Estimates of Humpback and Blue Whales Off California in 1991 92 written by John Calambokidis and published by . This book was released on 1993 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Journal of the Acoustical Society of America written by Acoustical Society of America and published by . This book was released on 2002 with total page 1636 pages. Available in PDF, EPUB and Kindle. Book excerpt:

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 The Stocks of Whales written by Neil Alison Mackintosh and published by . This book was released on 1965 with total page 264 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 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.