TY - JOUR

T1 - Acoustic detection range and population density of Cuvier's beaked whales estimated from near-surface hydrophones

AU - Barlow, Jay

AU - Fregosi, Selene

AU - Thomas, Len

AU - Harris, Danielle

AU - Griffiths, Emily T.

N1 - Funding Information: Funding for this research was provided by the U.S. Office of Naval Research (Project Nos. N00014-15-1-2142 and MIPR N0001416IP00059) and NOAA’s Southwest Fisheries Science Center. Vessel time on the Horizon was funded by NOAA’s Cooperative Research Program. Funding for DASBR development and some equipment was provided by the U.S. Navy’s N45 and Living Marine Resource programs and NOAA’s Acoustics Program. S.F. was supported by the National Science and Engineering Graduate Fellowship. We thank Mike Weise, Frank Stone, Jason Gedamke, Lisa Ballance, and Anu Kumar for their support. Field assistance was provided by Dave Mellinger, Holger Klinck, Jennifer McCullough, and Eiren Jacobson. Vessel operators were Trevor Oudin, Juan Carlos Aguilar, and Spencer Salmon. Analysis methods were developed with helpful ideas from Tiago Marques and Jeff Moore. This manuscript was improved by helpful comments from Jeff Moore. This is Pacific Marine Environmental Laboratory (PMEL) Contribution No. 5071. Publisher Copyright: © 2021 U.S. Government. Copyright: Copyright 2021 Elsevier B.V., All rights reserved.

PY - 2021/1

Y1 - 2021/1

N2 - The population density of Cuvier's beaked whales is estimated acoustically with drifting near-surface hydrophone recorders in the Catalina Basin. Three empirical approaches (trial-based, distance-sampling, and spatially explicit capture-recapture) are used to estimate the probability of detecting the echolocation pulses as a function of range. These detection functions are used with two point-transect methods (snapshot and dive-cue) to estimate density. Measurement errors result in a small range of density estimates (3.9-5.4 whales per 1000 km2). Use of multiple approaches and methods allows comparison of the required information and assumptions of each. The distance-sampling approach with snapshot-based density estimates has the most stringent assumptions but would be the easiest to implement for large scale surveys of beaked whale density. Alternative approaches to estimating detection functions help validate this approach. The dive cue method of density estimation has promise, but additional work is needed to understand the potential bias caused by animal movement during a dive. Empirical methods are a viable alternative to the theoretical acoustic modeling approaches that have been used previously to estimate beaked whale density.

AB - The population density of Cuvier's beaked whales is estimated acoustically with drifting near-surface hydrophone recorders in the Catalina Basin. Three empirical approaches (trial-based, distance-sampling, and spatially explicit capture-recapture) are used to estimate the probability of detecting the echolocation pulses as a function of range. These detection functions are used with two point-transect methods (snapshot and dive-cue) to estimate density. Measurement errors result in a small range of density estimates (3.9-5.4 whales per 1000 km2). Use of multiple approaches and methods allows comparison of the required information and assumptions of each. The distance-sampling approach with snapshot-based density estimates has the most stringent assumptions but would be the easiest to implement for large scale surveys of beaked whale density. Alternative approaches to estimating detection functions help validate this approach. The dive cue method of density estimation has promise, but additional work is needed to understand the potential bias caused by animal movement during a dive. Empirical methods are a viable alternative to the theoretical acoustic modeling approaches that have been used previously to estimate beaked whale density.

UR - http://www.scopus.com/inward/record.url?scp=85099205920&partnerID=8YFLogxK

U2 - 10.1121/10.0002881

DO - 10.1121/10.0002881

M3 - Journal article

C2 - 33514185

AN - SCOPUS:85099205920

VL - 149

SP - 111

EP - 125

JO - Acoustical Society of America. Journal

JF - Acoustical Society of America. Journal

SN - 0001-4966

IS - 1

ER -