Biological and Behavioral Response Studies of Marine Mammals in Southern California, 2011 (“SOCAL-11”) Final Project Report.

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NPS-OC-12-005CR.pdf (5.01 MB)
Authors
Southall, Brandon
Subjects
SOCAL-11
SOCAL-BRS
marine mammals
acoustic surveys
visual surveys
Southern California Bight
blue whales
beaked whales
Risso’s dolphin
Cuvier’s beaked whale
Baird’s beaked whale
Passive Acoustic Monitoring (PAM)
Advisors
Date of Issue
2012-09
Date
2012-09
Publisher
Monterey, California. Naval Postgraduate School
Department of Oceanography
Language
en_US
Abstract
This report summarizes the results from SOCAL-11, the second year of the research project Southern California Behavioral Response Study (SOCAL-BRS) conducted in the Southern California Bight. The study’s overall objective is to provide a better understanding of marine mammal behavior and a direct scientific basis to estimate the risk and minimize adverse effects of human sounds, particularly military sonar, on marine mammals. During a scouting phase and two operational legs of SOCAL-11, researchers observed, photographed, and/or tracked thousands of individuals of 18 marine mammal species. Thirty-eight tags were secured on 35 individual animals of four different marine mammal species, including many on focal species including blue whales, Risso’s dolphins, and Cuvier’s beaked whales. Eighteen controlled exposure experiments (CEEs) were conducted on eighteen individuals from three marine mammal species. Simulated military sonar signals and noise bands of comparable frequency were presented (under strict safety—for the animals—protocols) as stimuli. Changes in behavior from baseline conditions were measured as a function of sound exposure. Preliminary results based primarily on clearly observable behavior in the field and from initial data assessment indicate variable responses (that range from none to apparent temporary avoidance) depending upon species, type of sound, and behavioral state during the experiments. Results of sound source testing and verification prior to the start of SOCAL-11 fieldwork are also presented. Finally, results of Passive Acoustic Monitoring (PAM) using towed hydrophone arrays to detect and track beaked and sperm whales in real-time using their echolocation clicks are presented. It is concluded that, although localization could still be improved, distinguishing Cuvier’s from Baird’s and Mesoplodon beaked whales is now fairly reliable in real-time.
Type
Technical Report
Description
URI
https://hdl.handle.net/10945/13857
Series/Report No
Department
Oceanography
Organization
Identifiers
NPS Report Number
NPS-OC-12-005CR
Sponsors
Prepared for: Chief of Naval Operations Energy and Environmental Readiness Division, Washington, D.C.
Funder
N00244-10-1-0033
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Citation
Distribution Statement
Rights
This publication is a work of the U.S. Government as defined in Title 17, United States Code, Section 101. Copyright protection is not available for this work in the United States.
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