Acoustic methods are frequently used to monitor endangered marine mammal species. Advantages of acoustic methods over visual ones include the ability to detect submerged animals, to work at night, and to work in any weather conditions. A relatively inexpensive and easy-to-use acoustic float, the QUEphone, was developed by converting a...
The energy ratio mapping algorithm (ERMA) was developed to improve the performance of
energy-based detection of odontocete echolocation clicks, especially for application in environments
with limited computational power and energy such as acoustic gliders. ERMA systematically
evaluates many frequency bands for energy ratio-based detection of echolocation clicks produced
by a...
Full Text:
, Newport, Oregon 97365
(Received 23 February 2012; accepted 24 February 2012)
[DOI: 10.1121/1.3699190
The energy ratio mapping algorithm (ERMA) was developed to improve the performance of
energy-based detection of odontocete echolocation clicks, especially for application in environments
with limited computational power and energy such as acoustic gliders. ERMA systematically
evaluates many frequency bands for energy ratio-based detection of echolocation clicks produced
by a...
Full Text:
pilot whales). VC 2011 Acoustical Society of America. [DOI: 10.1121/1.3531924]
PACS number(s): 43.30.Sf
The energy ratio mapping algorithm (ERMA) was developed to improve the performance of
energy-based detection of odontocete echolocation clicks, especially for application in environments
with limited computational power and energy such as acoustic gliders. ERMA systematically
evaluates many frequency bands for energy ratio-based detection of echolocation clicks produced
by a...
Acoustic backscattering strength is often used as an index of biomass; however, the relationship between these variables has not been directly validated. Relationships were investigated between acoustic cross section at 200 kHz, measured as part of a previous study, and measured values of length, biovolume, dry weight, ash-free dry weight,...
Fluctuations of the low frequency sound field in the presence of an internal solitary wave packet during the Shallow Water ’06 experiment are analyzed. Acoustic, environmental, and on-board ship radar image data were collected simultaneously before, during, and after a strong internal solitary wave packet passed through the acoustic track....
In 2009 two calibrated acoustic recorders were deployed in polar waters of the North Atlantic to study the seasonal occurrence of blue, fin, and sperm whales and to assess current ambient noise levels. Sounds from these cetaceans were recorded at both locations in most months of the year. During the...
Vocalizations of Indo-Pacific humpback dolphins (Sousa chinensis) in west Hong Kong waters were described from 12 recordings in 2010. A broadband hydrophone system recorded sounds. Vocalizations were characterized as broadband click trains, burst pulses, and narrowband frequency modulated sounds, including whistles generally similar to those of some other delphinid cetaceans....
Humpback whales produce a wide range of low-to mid-frequency vocalizations throughout their migratory range. Non-song "calls" dominate this species' vocal repertoire while on high-latitude foraging grounds. The source levels of 426 humpback whale calls in four vocal classes were estimated using a four-element planar array deployed in Glacier Bay National...
Preliminary results are presented from an analysis of mid-frequency acoustic transmission data collected at range 550m during the Shallow Water 2006 Experiment. The acoustic data were collected on a vertical array immediately before, during, and after the passage of a nonlinear internal wave on 18 August, 2006. Using oceanographic data...