title: Beaked whale (Mesoplodon densirostris) passive acoustic detection in increasing ambient noise.
abstract: Passive acoustic detection is being increasingly used to monitor visually cryptic cetaceans such as Blainville's beaked whales (Mesoplodon densirostris) that may be especially sensitive to underwater sound. The efficacy of passive acoustic detection is traditionally characterized by the probability of detecting the animal's sound emissions as a function of signal-to-noise ratio. The probability of detection can be predicted using accepted, but not necessarily accurate, models of the underwater acoustic environment. Recent field studies combining far-field hydrophone arrays with on-animal acoustic recording tags have yielded the location and time of each sound emission from tagged animals, enabling in-situ measurements of the probability of detection. However, tagging studies can only take place in calm seas and so do not reflect the full range of ambient noise conditions under which passive acoustic detection may be used. Increased surface-generated noise from wind and wave interaction degrades the signal-to-noise ratio of animal sound receptions at a given distance leading to a reduction in probability of detection. This paper presents a case study simulating the effect of increasing ambient noise on detection of M. densirostris foraging clicks recorded from a tagged whale swimming in the vicinity of a deep-water, bottom-mounted hydrophone array.
authors.affiliation: Naval Undersea Warfare Center, Division Newport, 1176 Howell Street, Newport, Rhode Island, USA. jessica.ward@navy.mil
authors.forename: Jessica
authors.initials: J
authors.lastname: Ward
authors.forename: Susan
authors.initials: S
authors.lastname: Jarvis
authors.forename: David
authors.initials: D
authors.lastname: Moretti
authors.forename: Ronald
authors.initials: R
authors.lastname: Morrissey
authors.forename: Nancy
authors.initials: N
authors.lastname: Dimarzio
authors.forename: Mark
authors.initials: M
authors.lastname: Johnson
authors.forename: Peter
authors.initials: P
authors.lastname: Tyack
authors.forename: Len
authors.initials: L
authors.lastname: Thomas
authors.forename: Tiago
authors.initials: T
authors.lastname: Marques
mesh_terms: D000162:Acoustics / Q000295:instrumentation; D000818:Animals; D003198:Computer Simulation; D004784:Environmental Monitoring / Q000295:instrumentation; D005247:Feeding Behavior; D005260:Female; D005583:Fourier Analysis; D008297:Male; D009622:Noise / Q000009:adverse effects*; D012815:Signal Processing, Computer-Assisted; D013018:Sound Spectrography; D013550:Swimming; D014159:Transducers; D014828:Vocalization, Animal; D014907:Whales / Q000502:physiology*