title: The effect of depth on the target strength of a humpback whale (Megaptera novaeangliae).
abstract: Marine mammals are very seldom detected and tracked acoustically at different depths. The air contained in body cavities, such as lungs or swimbladders, has a significant effect on the acoustic energy backscattered from whale and fish species. Target strength data were obtained while a humpback whale (Megaptera novaeangliae) swam at the surface and dove underneath a research vessel, providing valuable multi-frequency echosounder recordings of its scattering characteristics from near surface to a depth of about 240 m. Increasing depth dramatically influenced the backscattered energy coming from the large cetacean. This study is tightly linked to the ultimate goal of developing an automated whale detection system for mitigation purposes.
authors: Institute of Marine Research, P.O. Box 1870, Nordnes 5817 Bergen, Norway.
authors: M
authors: M
authors: Bernasconi
authors: CodeLab Bergen, Klostergaten 26, 5005 Bergen, Norway.
authors: R
authors: R
authors: Patel
authors: Institute of Marine Research, P.O. Box 1870, Nordnes 5817 Bergen, Norway.
authors: L
authors: L
authors: Nøttestad
authors: Christian Michelsen Research AS, P.O. Box 6031, NO-5892, Bergen, Norway.
authors: G
authors: G
authors: Pedersen
authors: Pelagic Ecology Research Group, Scottish Oceans Institute, University of St Andrews, St Andrews, Fife, KY16 8LB, Scotland, United Kingdom.
authors: A S
authors: AS
authors: Brierley
mesh_terms: D000162:Acoustics; D000818:Animals; D001331:Automation; D004242:Diving; D004784:Environmental Monitoring / Q000379:methods*; D050640:Humpback Whale / Q000502:physiology*; D009038:Motion; D009792:Oceans and Seas; D012542:Scattering, Radiation; D012815:Signal Processing, Computer-Assisted; D013016:Sound; D013018:Sound Spectrography; D013997:Time Factors