Download or read book Fin Whale Acoustics as a Tool to Assess Stock Structure in the North Pacific written by Benjamin Jones and published by . This book was released on 2011 with total page 23 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Understanding stock structure is a key component to effective wildlife management (Wiens 1989, Shea et al. 1998). When the spatial distribution of a species during the breeding season is split into a number of independently breeding subpopulations, each referred to as a population stock (Wiens 1989), unique conservation measures must be applied in order to minimize extirpations and genetic loss. In order to accurately predict the population dynamics and response to environmental and anthropogenic changes, resource managers must understand the location and size of these stocks"--Introduction.
Download or read book Future directions for acoustic marine mammal surveys stock assessment and habitat use report of a workshop held in La Jolla California 2022 November 2002 written by and published by DIANE Publishing. This book was released on with total page 45 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 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 Biology and Ecology of Antarctic Krill written by Volker Siegel and published by Springer. This book was released on 2016-08-03 with total page 458 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book gives a unique insight into the current knowledge of krill population dynamics including distribution, biomass, production, recruitment, growth and mortality rates. Detailed analysis is provided on food and feeding, reproduction and krill behaviour. The volume provides an overview on the aspects of natural challenges to the species, which involve predation, parasites and the commercial exploitation of the resource and its management. A chapter on genetics shows the results of population subdivision and summarizes recent work on sequencing transcriptomes for studying gene function as part of the physiology of live krill. The focus of Chapter 4 is on physiological functions such as biochemical composition, metabolic activity and growth change with ontogeny and season; and will demonstrate which environmental factors are the main drivers for variability. Further discussed in this chapter are the bottle necks which occur in the annual life cycle of krill, and the mechanisms krill have adapted to cope with severe environmental condition.
Download or read book The Journal of Cetacean Research and Management written by and published by . This book was released on 2008 with total page 600 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Baleen Whale Acoustic Activity in the North Pacific written by Kathleen M. Stafford and published by . This book was released on 2007 with total page 25 pages. Available in PDF, EPUB and Kindle. Book excerpt: Unclassified historic acoustic data were used to examine long time scale changes in the seasonal and geographic occurrence of large whales in the Pacific and to correlate these changes with oceanographic variables such as sea surface temperature, chlorophyll a, etc. Distribution of northeastern Pacific blue whales (as indicated by the numbers of their calls), while insignificantly related to SST, did show a clear seasonal pattern both to chl a concentration (negative) and to the mixed layer depth (positive). It was speculated that the negative correlation with chl a might be due to a lag from primary to secondary productivity: as phytoplankton are eaten by zooplankton (which in turn become available to whales), the overall amount of chl a decreases. It is recommended that in collaboration with other agencies hydrophones be deployed in the northeastern Gulf of Alaska to provide current information on the occurrence of vocally active whale species, including low frequency baleen whales and higher frequency odontocetes. A likely time might be during the Northern Edge 2008 exercise in Prince William Sound. Meanwhile, a new efficient, low-power, low-cost recorder that can be easily deployed, in an array with other instruments or independently, from a mid-size vessel is being developed.
Download or read book Distribution of Calling Blue Fin and Humpback Whales in the North Pacific written by and published by . This book was released on 2000 with total page 70 pages. Available in PDF, EPUB and Kindle. Book excerpt: The seasonal distribution of calling blue whales (Balaenoptera musculus) and fin whales (B. physalus), and singing humpback whales (Megaptera novaeangliae) has been analyzed from acoustic data recorded by U.S. Navy Sound Surveillance System (SOSUS) and other hydrophone arrays in the North Pacific. The data from ten arrays were selected as representative of four Regions along the continental margins, labeled Northwest (NW), Northcentral (NC), Northeast (NE), and Southeast (SE). The call data indicate that there is a substantial population of blue whales scattered over the North Pacific and concentrated during the Fall season in the NW and NC Regions. Blue whale calls are recorded in all seasons, particularly in these NW and NC Regions. Fin whales are found in groups but also in relatively large numbers in all Regions, with most calling in the Winter season and in the NC Region, and calling is absent in most Regions during Summer. Fin whale calling includes "F" calls from individuals heard in all seasons and "J" calls from too many whales to separate, particularly prominent in the winter reproductive season. Humpback singing is recorded most in the NC and SE Regions at the time of their Winter/Spring migration. The distribution of singing humpbacks changed in both the NC and SE Regions between the 1996-1997 and 1998-2000 periods.
Download or read book Toward an Ecosystem Approach for the Western Pacific Region from Species based Fishery Management Plans to Place based Fishery Ecosystem Plans written by and published by . This book was released on 2009 with total page 660 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Methods for Characterizing Fin Whale Song Notes for Comparative Studies of Geographic Variation in Song written by Shannon Rankin and published by . This book was released on 2018 with total page 33 pages. Available in PDF, EPUB and Kindle. Book excerpt: The identification and delineation of 'stocks' (management units of a species ranging from independent populations to subspecies) is important for understanding and mitigating potential sources of human-caused mortality. This is especially critical for endangered and protected species, such as the large whales. Stock identification for whales has typically been based on ecology, life history, morphology, and genetics. However, for many species, acoustic differences in whale call types may indicate the presence of unidentified populations or subspecies. The potential role of acoustics in identifying structure at various levels of divergence in cetaceans has been recognized in numerous publications; however, this potential has yet to be implemented for large whales. In an effort to include acoustic data in this process, we are contributing to current efforts to update the status of endangered fin whales (Balaenoptera physalus) in the North Pacific. An analysis of North Pacific fin whale populations based on identification of ‘song’ provides hypotheses that can be tested with other lines of evidence such as genetics. Standardized methods for processing recordings from autonomous recorders will be presented in detail with a summary of the data to be processed and published on peer-reviewed contributions.
Download or read book Workshop on the Biology and Target Acoustics of Marine Life written by John W. Foerster and published by . This book was released on 1985 with total page 232 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Whale Call Data for the North Pacific written by and published by . This book was released on 2000 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt: Calls of blue whales (Balaenoptera musculus), fin whales (Balaenoptera physalus), and humpback whales (Megaptera novaeangliae) were identified in the data from U.S. Navy Sound Surveilance System (SOSUS) and other hydrophone arrays. These data on calling whales from November 1995 through July 1999 have been listed here for four offshore, deep-water Regions along continental margins of the North and Northeast Pacific. The occurrence of calling whales was monitored during two-day periods each week. Call data recorded from each array identified species, call occurrence, variation, received beam, and relative numbers of calling whales. This allowed assessment of seasonal distribution of calls for the different species, and provided locations for sources received at multiple arrays. Blue whale tonal sounds were distributed widely, received most in the NW Region, with a peak in occurrence in the fall. Fin whale "20-Hz" repetitive pulse sequences were received from whales grouped in local areas in all Regions, with a peak in occurrence in midwinter. Humpback songs were received from December through May particularly in the SE Region. The offshore listening systems allowed basin-wide monitoring of the seasonal distribution of these callng whales.
Download or read book Identifying and Comparing Important Areas for Marine Sustainable Use and Conservation written by Sofie Van Parijs and published by Frontiers Media SA. This book was released on 2024-05-24 with total page 342 pages. Available in PDF, EPUB and Kindle. Book excerpt: The ocean is under increasing threat from the expansion of human activities. The combined impacts of these threats as well as the potential impacts of climate change and ocean acidification have placed thousands of species at risk of extinction, and have impaired the structure, function, productivity and resilience of marine ecosystems. Currently, some parts of the world's oceans are significantly impacted, yet are without any form of effective management. Only a small proportion of the oceans are within protected area systems. Globally, measures are being taken to increase protection and sustainable management, but application is uncoordinated and not always effective. In order to support effective policy action by countries and competent international and regional organizations, it is critical to build a sound understanding of the most ecologically and biologically important ocean areas that support healthy marine ecosystems so that the necessary steps to ensure the long-term function and resilience of these systems can be taken.
Download or read book North Pacific Acoustic Laboratory written by and published by . This book was released on 2001 with total page 530 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Cape Wind Energy Project written by and published by . This book was released on 2009 with total page 1222 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Atlantic Coast of Maryland Shoreline Protection Project General Reevaluation Study Borrow Sources for 2010 2044 written by and published by . This book was released on 2008 with total page 470 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Marine Fisheries Review written by and published by . This book was released on 1999 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt:
