Using line acceleration to measure false killer whale (Pseudorca crassidens) source levels during pelagic longline depredation

False killer whales (Pseudorca crassidens) depredate pelagic longlines in offshore Hawaiian waters. On January 28, 2015¿a depredation event was recorded 14¿m from an integrated GoPro camera, hydrophone, and accelerometer, revealing that false killer whales depredate bait and generate clicks and whistles under good visibility conditions. The act of plucking bait off a hook generated a distinctive 15¿Hz line vibration. Two similar line vibrations detected at earlier times permitted the animal's range and thus signal source levels to be estimated over a 25-min window. Peak power spectral density source levels for whistles (4–8¿kHz) were estimated to be between 115 and 130¿dB re 1¿µPa2/Hz @ 1¿m. Echolocation click source levels over 17–32¿kHz bandwidth reached 205¿dB re 1¿µPa @ 1¿m pk-pk, or 190¿dB re 1¿µPa @ 1¿m (root-mean-square). Predicted detection ranges of the most intense whistles are 10 to 25¿km at respective sea states of 4 and 1, with click detection ranges being 5 times smaller than whistles. These detection range analyses provide insight into how passive acoustic monitoring might be used to both quantify and avoid depredation encounters.

Thode, A., L. Wild, J. Straley, D. Barnes, A. Bayless, V. O’Connell, E. Oleson, J. Sarkar, D. Falvey, L. Behnken, S. Martin. 2016. Using line acceleration to measure false killer whale (Pseudorca crassidens) click and whistle source levels during pelagic longline depredation. JASA 140:4288-4297. doi:10.1121/1.4968853.

Data access is governed by the terms of the grant from NOAA's Bycatch Reduction Engineering Program to the University of California San Diego.

BREP Requirement:

Data Sharing Plan- Environmental data and information collected and/or created under NOAA grants/ cooperative agreements must be made visible, accessible, and independently understandable to general users, free of charge or at minimal cost, in a timely manner (typically no later than two (2) years after the data are collected or created), except where limited by law, regulation, policy or security requirements. (a) Unless otherwise noted in the federal funding announcement, a Data/Information Sharing Plan of no more than two pages shall be required. A typical plan should include descriptions of the types of environmental data and information created during the course of the project; the tentative date by which data will be shared; the standards to be used for data/metadata format and content; policies addressing data stewardship and preservation; procedures for providing access, sharing, and security; and prior experience in publishing such data.

(b) The Data/Information Sharing Plan (and any subsequent revisions or updates) must be made publicly available at time of award and, thereafter, will be posted with the published data.

(c) Failing to share environmental data and information in accordance with the submitted Data/Information Sharing Plan may lead to disallowed costs and be considered by NOAA when making future award decisions.

(d) If your proposed activities do not generate any environmental data, your application is still required to have a data sharing plan. Such a data sharing plan could include the statement that “this project will not generate any environmental data”.

UCSD Data Sharing Plan:

The data yielded from this project has four forms: time/spatial information, passive acoustic data, groups of camera images, and acceleration data. For each deployment, all four data types would be stored on backup external hard drives at UAS, with an additional copy shipped to SIO. The time/spatial information would be stored in Microsoft Excel spreadsheet form, and the camera images stored in standard JPEG form, thus making them easily accessible to others in the community. The passive acoustic data are stored in a raw data format along with a text file describing the sampling rate, and start and end times of the data file. A copy of a MATLAB program to import the data will be stored on each individual hard drive.

A subset of images and sound clips that document encounters would be posted on an SIO website (http://scripps.ucsd.edu/labs/athode) and www.seaswap.info. Interested parties wishing access to complete deployment data would be asked to send a portable hard drive to SIO, given that the expected volume of stored data for one deployment will be on the order of 200 Gb.

A subset of images and sound clips that document encounters would be posted on an SIO website (http://scripps.ucsd.edu/labs/athode) and www.seaswap.info. Interested parties wishing access to complete deployment data would be asked to send a portable hard drive to SIO (A. Thode- athode@ucsd.edu), given that the expected volume of stored data for one deployment will be on the order of 200 Gb.

Data access is governed by the terms of the grant from NOAA's Bycatch Reduction Engineering Program to the University of California San Diego.