Download or read book The Detection and Analysis of Fin Whale Vocalizations Recorded Offshore of Galicia written by Jamie Burford and published by . This book was released on 2015 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Characteristics of Fin Whale Vocalizations Recorded on Instruments in the Northeast Pacific Ocean written by Maria Michelle Josephine Weirathmueller and published by . This book was released on 2016 with total page 123 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis focuses on fin whale vocalizations recorded on ocean bottom seismometers (OBSs) in the Northeast Pacific Ocean, using data collected between 2003 and 2013. OBSs are a valuable, and largely untapped resource for the passive acoustic monitoring of large baleen whales. This dissertation is divided into three parts, each of which uses the recordings of fin whale vocalizations to better understand their calling behaviors and distributions. The first study describes the development of a technique to extract source levels of fin whale vocalizations from OBS recordings. Source levels were estimated using data collected on a network of eight OBSs in the Northeast Pacific Ocean. The acoustic pressure levels measured at the instruments were adjusted for the propagation path between the calling whales and the instruments using the call location and estimating losses along the acoustic travel path. A total of 1241 calls were used to estimate an average source level of 189 +/-5.8 dB re 1uPa @ 1m. This variability is largely attributed to uncertainties in the horizontal and vertical position of the fin whale at the time of each call, and the effect of these uncertainties on subsequent calculations. The second study describes a semi-automated method for obtaining horizontal ranges to vocalizing fin whales using the timing and relative amplitude of multipath arrivals. A matched filter is used to detect fin whale calls and pick the relative times and amplitudes of multipath arrivals. Ray-based propagation models are used to predict multipath times and amplitudes as function of range. Because the direct and first multiple arrivals are not always observed, three hypotheses for the paths of the observed arrivals are considered; the solution is the hypothesis and range that optimizes the fit to the data. Ray-theoretical amplitudes are not accurate and solutions are improved by determining amplitudes from the observations using a bootstrap method. Data from ocean bottom seismometers at two locations are used to assess the method: one on the Juan de Fuca Ridge, a bathymetrically complex mid-ocean ridge environment, and the other at a flat sedimented location in the Cascadia Basin. At both sites, the method is reliable up to ~4 km range which is sufficient to enable estimates of call density. The third study explores spatial and temporal trends in fin whale calling patterns. The frequency and inter-pulse interval of fin whale 20 Hz vocalizations were observed over 10 years from 2003-2013 on bottom mounted hydrophones and OBSs in the northeast Pacific Ocean. The instrument locations extended from 40°N and 130°W to 125°W with water depths ranging from 1500-4000 m. The inter-pulse interval (IPI) of fin whale song sequences was observed to increase at a rate of 0.59 seconds/year over the decade of observation. During the same time period, peak frequency decreased at a rate of 0.16 Hz/year. Two primary call patterns were observed. During the earlier years, the more commonly observed pattern had a single frequency and single IPI. In later years, a doublet pattern emerged, with two dominant frequencies and two IPIs. Many call sequences in the intervening years appeared to represent a transitional state between the two patterns. The overall trend was consistent across the entire geographical span, although some regional differences exist.
Download or read book Tracking and Monitoring Fin Whales Offshore the Galicia Margin Using Passive Acoustic Methods written by Jessica Fisher and published by . This book was released on 2017 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Singing Fin Whales Tracked Acoustically Offshore of Southern California written by Leah McLean Varga and published by . This book was released on 2016 with total page 45 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fin whales (Balaenoptera physalus) produce a stereotyped low frequency call (15-30 Hz) that can be detected at great range and is considered song when produced in a repeated pattern. These calls, referred to as 20 Hz calls, were localized and animals were tracked using a kilometer-scale array of four passive acoustic recorders deployed at approximately 800m depth, northwest of San Clemente Island in the Southern California Bight. A total of 4969 calls were localized over four continuous weeks during late fall of 2007. The average estimated source level for the localized calls was 190.9 ± 7.4 dB peak-to-peak re 1[mu]Pa2 at 1m. The majority of the calls in these data were in the form of a doublet song pattern, with average inter-pulse intervals (IPI) 13s and 18s. The tracks were the first to be recorded for singing fin whales transiting alone using passive acoustic monitoring. Acoustic tracking of fin whales provides insight into the ecology and behavior of the species. Estimating call source levels help future predictions of how these whales are impacted by anthropogenic noise. Call source level, along with calling behavior, provide important parameters required for population density estimation. Furthermore, studying fin whale song patterns may aid in distinguishing different subpopulations.
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 Noisy Oceans written by Gaye Bayrakci and published by John Wiley & Sons. This book was released on 2023-12-19 with total page 293 pages. Available in PDF, EPUB and Kindle. Book excerpt: Noisy Oceans Measuring devices such as ocean bottom seismometers and hydrophones designed to detect earthquakes pick up many other signals. These were previously ignored as background noise from unknown sources, but advanced technology now allows insights into the noise created from icebergs, ships, hydrothermal vents, whales, rain, marine engineering, and more. Noisy Oceans: Monitoring Seismic and Acoustic Signals in the Marine Environment is a comprehensive guide to non-tectonic marine noise originating from different environmental, biological, and anthropogenic sources. Volume highlights include: Overview of marine soundscapes and their sources Existing and new methods for studying acoustic signals Case studies from around the world Spans disciplines from geology and geophysicists to biology Explores the impacts and implications of marine noise The American Geophysical Union promotes discovery in Earth and space science for the benefit of humanity. Its publications disseminate scientific knowledge and provide resources for researchers, students, and professionals.
Download or read book Detection and Analysis of Low frequency Sperm Whale Vocalizations with a Towed Array written by Alexander Bohn and published by . This book was released on 2015 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sperm whale vocalizations recorded during a sea test and calibration experiment in the Gulf of Maine on a single towed, horizontal, densely sampled, low-frequency (
Download or read book Characterization of St Lawrence Blue Whale Vocalizations and Their Correlation with Field Observations written by Catherine L. Berchok and published by . This book was released on 2004 with total page 442 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 Site Specific Passive Acoustic Detection and Densities of Humpback Whale Calls Off the Coast of California written by Tyler Adam Helble and published by . This book was released on 2013 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt: Passive acoustic monitoring of marine mammal calls is an increasingly important method for assessing population numbers, distribution, and behavior. Automated methods are needed to aid in the analyses of the recorded data. When a mammal vocalizes in the marine environment, the received signal is a filtered version of the original waveform emitted by the marine mammal. The waveform is reduced in amplitude and distorted due to propagation effects that are influenced by the bathymetry and environment. It is important to account for these effects to determine a site-specific probability of detection for marine mammal calls in a given study area. A knowledge of that probability function over a range of environmental and ocean noise conditions allows vocalization statistics from recordings of single, fixed, omnidirectional sensors to be compared across sensors and at the same sensor over time with less bias and uncertainty in the results than direct comparison of the raw statistics. This dissertation focuses on both the development of new tools needed to automatically detect humpback whale vocalizations from single-fixed omnidirectional sensors as well as the determination of the site-specific probability of detection for monitoring sites off the coast of California. Using these tools, detected humpback calls are "calibrated" for environmental properties using the site-specific probability of detection values, and presented as call densities (calls per square kilometer per time). A two-year monitoring effort using these calibrated call densities reveals important biological and ecological information on migrating humpback whales off the coast of California. Call density trends are compared between the monitoring sites and at the same monitoring site over time. Call densities also are compared to several natural and human-influenced variables including season, time of day, lunar illumination, and ocean noise. The results reveal substantial differences in call densities between the two sites which were not noticeable using uncorrected (raw) call counts. Additionally, a Lombard effect was observed for humpback whale vocalizations in response to increasing ocean noise. The results presented in this thesis develop techniques to accurately measure marine mammal abundances from passive acoustic sensors.
Download or read book An Analysis of Wild Killer Whale Orcinus Orca Vocalizations Recorded in Mc Murdo Sound Antarctica written by Stephanie Lynn Billon and published by . This book was released on 1984 with total page 156 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 2006 with total page 988 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fin Whale Distribution in the Indian and Equatorial Pacific Oceans in Support of Passive Acoustic Density Estimation written by Julia Vernon and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The use of passive acoustic monitoring in population density estimation of marine mammals is a developing capability, providing an efficient and cost-effective alternative to visual surveys. However, this method of density estimation introduces new challenges. Passive acoustic density estimation incorporates several variables, including the number of animal vocalizations detected over a period of time, the probability of detecting vocalizations in a given area, and the vocalization rate of the species of interest. Automatic detectors are needed to quickly and effectively detect vocalizing animals in a large data set. Such detectors need to be assessed for effectiveness, accounting for inefficiencies and quantifying the probability of detecting a vocalization by the species of interest. Another challenge that arises is uncertainty in the geographic distribution of individuals. Estimating distribution through consideration of the horizontal azimuths of vocalizing animals reduces bias introduced by the assumption that on average, animals are uniformly distributed around the sensors.Low-frequency ambient noise data (
Download or read book Spatio temporal Patterns in Antarctic Minke Whale Balaenoptera Bonaerensis Vocal Behaviour in the Weddell Sea written by Diego Andrés Filun Hernández and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Antarctic minke whales (AMW) have a circum-antarctic distribution and are known to occur in both open and ice-covered waters of the Southern Ocean (SO). They are a pagophilic species and are regularly observed in heavily sea-ice covered areas. Because of this, current knowledge about Antarctic minke whales is scarce and limited to austral summer and ice-free regions where the majority of visual survey data have been collected. Hence, very little is known on their winter distribution in high latitude waters and to what extent the wintering individuals that are occasionally observed in Antarctic waters represent single observations or a structurally present behavioral trait of the species. Likewise, AMW population structure is poorly known. As most baleen whale species, AMWs are known to undertake annual migrations between high latitude feeding areas and low latitude breeding areas. However, available data to date suggest that for AMWs, migrations seem more protracted and complex than in other baleen whale species. The recent identification of vocalizations produced by AMWs (“bio-duck call”) now makes it possible to also use passive acoustic technology to study occurrence patterns and behavior. Passive acoustic monitoring (PAM) offers a versatile technology with which long-term archival data can be collected on sound-producing species using autonomous recording units. Acoustic observation has the additional advantages that it can continue data collection independent of light conditions and under poor weather conditions. Furthermore, it can monitor large areas at the same time, since it collects data omnidirectionally, and it can collect data over extended periods (i.e., multi-year time scales) through the use of autonomous devices. In the scope of this doctoral thesis, I analysed passive acoustic data from high and low latitudes collected in the Atlantic Ocean sector of the Southern Ocean (Weddell Sea) and southern Atlantic Ocean, to investigate spatio-temporal patterns in the acoustic presence and vocal behaviour of AMWs. In Chapter I, I investigate year-round spatial- temporal patterns in AMW occurrence in ice-covered areas. Our analysis was based on a 9-year passive acoustic dataset (2008- 2016) from 21 locations throughout the Weddell Sea (WS). AMW bio-duck calls were detected acoustically at all mooring locations from May to December, with the highest presence between August and November (bio-duck calls present at more than 80% of days). At the southernmost recording locations, bio-duck calls were present up to 10 months of the year. We identified a substantial inter-annual variation in the seasonality of vocal activity correlated to variation in local ice concentration. Our analysis indicates that part of the AMW population stays in the Weddell Sea during austral winter. In Chapter II, I used PAM data from 6 positions located along the WS during 2013 as well as three consecutive years of PAM data (2015-2016-2017) recorded at the stationary coastal acoustic observatory PALAOA to study both spatial and inter-annual variability in the acoustic behavior of AMWs. During 2013, between May and December throughout the WS, we detected 11 different bio-duck call types. The comparative analyses of the AMW bio-duck call repertoire throughout the WS showed that these 11 call types can be attributed to four call type groups. Furthermore, multi-year data from PALAOA on AMW repertoire composition showed an inter-annual difference in bio-duck call type usage. The observed patterns in AMW vocal behavior show that AMW vocal behavior matches the definition of song, exhibiting regional differences and highly dynamic revolutions over time. This study provides new information to potentially explore stock structures and movement patterns using passive acoustic methods. In Chapter III, my work addressed the occurrence of the AMW through bio-duck acoustic detections in the Santos Basin, South-Southeastern Brazil (22o and 28o S / 42o and 48o W), recorded between 12 November and 19 December 19, 2015, utilizing advanced passive acoustic technologies, i.e., an autonomous underwater vehicle (SeaGlider), for sampling. AMW calls were detected during 12 days. We detected and classified 9 different bio-duck calls in Brazilian coastal waters, evidencing a highly diverse acoustic behavior on this potential Antarctic minke whale breeding ground. Finally, in Chapter IV, our study investigated the temporal patterns of acoustic occurrence of baleen whales in a presumed baleen whale breeding area off Namibia. Our results show seasonal acoustic presence of humpback whales, fin whales and Antarctic minke whales from November to January and from June to August. Their acoustic absence from February to May possibly indicates that most animals migrated to other areas (presumably in higher latitudes) in austral summer to feed. Our findings support the presumed ecological importance of the oceanic area off Namibia, providing (part of) a suitable cetacean wintering and, possibly, breeding range or migratory corridor. Furthermore, the occurrence of Antarctic blue and minke whales off Namibia, concurrent with their reported acoustic presence in high-latitude feeding areas, adds to growing evidence that baleen whale migration is not obligate but much more dynamic than previously assumed. Overall, this PhD thesis highlights the significance of using long-term and large-scale datasets for the investigation of distribution patterns, habitat preferences, behavior and the effects of environmental variation on AMW distribution. The results present new information about fundamental and ecological knowledge of AMWs that can be implemented for the conservation and management of populations and ecosystems.
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 Effects of EMFs from Undersea Power Cables on Elasmobranchs and Other Marine Species Final Report written by T. Tricas and published by DIANE Publishing. This book was released on 2012-12 with total page 426 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Maritime Traffic Effects on Biodiversity in the Mediterranean Sea written by Ameer Abdulla and published by IUCN. This book was released on 2008 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt:
