DOI: 10.5061/dryad.8gtht76w1
title: Ziphius cavirostris presence relative to vertical and temporal variability of oceanographic conditions in the southern california bight

description: The oceanographic conditions of the Southern California Bight (SCB)
 dictate the distribution and abundance of prey resources and therefore the
 presence of mobile predators, such as goose-beaked whales (Ziphius
 cavirostris). Goose-beaked whales are deep-diving odontocetes that spend a
 majority of their time foraging at depth. Due to their cryptic behavior,
 little is known about how they respond to seasonal and interannual changes
 in their environment. This study utilizes passive acoustic data recorded
 from two sites within the SCB to explore the oceanographic conditions that
 goose-beaked whales appear to favor. Utilizing optimum multiparameter
 analysis, modeled temperature and salinity data are used to identify and
 quantify these source waters: Pacific Subarctic Upper Water (PSUW),
 Pacific Equatorial Water (PEW), and Eastern North Pacific Central Water
 (ENPCW). The interannual and seasonal variability in goose-beaked whale
 presence was related to the variability in El Niño Southern Oscillation
 events and the fraction and vertical distribution of the three source
 waters. Goose-beaked whale acoustic presence was highest during the winter
 and spring and decreased during the late summer and early fall. These
 seasonal increases occurred at times of increased fractions of PEW in the
 California Undercurrent and decreased fractions of ENPCW in surface
 waters. Interannual increases in goose-beaked whale presence occurred
 during El Niño events. These results establish a baseline understanding of
 the oceanographic characteristics that correlate with goose-beaked whale
 presence in the SCB. Furthering our knowledge of this elusive species is
 key to understanding how anthropogenic activities impact goose-beaked
 whales.
description: Acoustic data was collected using High-frequency Acoustic
 Recording Packages (HARPs, Wiggins and Hildebrand, 2007), passively
 recorded the ocean soundscape with a 200 kHz sampling frequency and 16-bit
 quantization, resulting in an effective bandwidth of 10 Hz to 100 kHz.
 Each HARP hydrophone was calibrated in the laboratory before initial
 deployment, while representative full systems were also calibrated at the
 US Navy’s Transducer Evaluation Center facility to verify the laboratory
 calibrations. Consistent deployments provided a near-continuous time
 series at both acoustic monitoring sites. Any gaps in the time series were
 due to battery life, data storage capacity, system failure, and/or vessel
 and crew availability to service the instruments.
 Goose-beaked whale echolocation signals were identified using a
 combination of automated detection and manual verification techniques
 (Baumann-Pickering et al., 2014). All echolocation clicks were first
 identified using the automated Teager Kaiser energy detector (Soldevilla
 et al., 2008: Roch et al., 2011). Individual click detections were then
 filtered with a 10-pole Butterworth band-pass filter with a passband
 between 5 kHz and 95 kHz. The absence or presence of beaked whale FM
 echolocation pulses was determined based on 75 second segments with a
 minimum requirement of seven detections. These segments were then
 classified as containing beaked whale presence if more than 13% of all
 initially detected signals had peak and center frequencies above 32 and 25
 kHz, a duration longer than 355 μs, and an upsweep rate of more than 23
 kHz/ms (Baumann-Pickering et al., 2013). The
 automatically detected beaked whale clicks were then verified using
 DetEdit, an open-source software for visualizing events within large
 acoustic datasets (Solsona-Berga et al., 2020). Once clicks were verified
 by a trained analyst, the number of FM pulse positive minutes was summed
 for each day and month. Goose-beaked whale presence data was determined as
 the number of FM pulse positive minutes recorded. Total monthly minutes of
 goose-beaked whale presence were used to examine the seasonal and
 interannual patterns in presence. Finally, to account for variations in
 recording efforts over time at each site, minutes of presence were divided
 by percent effort for each month. References:
 Baumann-Pickering, S., McDonald, M. A., Simonis, A. E., Solsona
 Berga, A., Merkens, K. P. B., Oleson, E. M., Roch, M. A., Wiggins, S. M.,
 Rankin, S., Yack, T. M., & Hildebrand, J. A. (2013).
 Species-specific beaked whale echolocation signals. <em>Journal of
 the Acoustical Society of America, 134</em>, 2293-2301. https://doi.org/10.1121/1.4817832 Baumann-Pickering, S., Roch, M. A., Brownell Jr, R. L., Simonis, A. E., McDonald, M. A., Solsona-Berga, A., Oleson, E. M., Wiggins, S. M., & Hildebrand, J. A. (2014). Spatio-temporal patterns of beaked whale echolocation signals in the North Pacific. PLoS ONE, 9(1). https://doi.org/10.1371/journal.pone.0086072 Roch, M. A., Klinck, H., Baumann-Pickering, S., Mellinger, D. K., Qui, S., Soldevilla, M. S., & Hildebrand, J. A. (2011). Classification of echolocation clicks from Odontocetes in the Southern California bight. The Journal of the Acoustical Society of America, 129(1), 467–475. https://doi.org/10.1121/1.3514383  Soldevilla, M. S., Henderson, E. E., Campbell, G. S., Wiggins, S. M., Hildebrand, J. A., & Roch, M. A. (2008). Classification of risso’s and Pacific white-sided dolphins using spectral properties of echolocation clicks. The Journal of the Acoustical Society of America, 124(1), 609–624. https://doi.org/10.1121/1.2932059  Solsona-Berga, A., Frasier, K. E., Baumann-Pickering, S., Wiggins, S. M., & Hildebrand, J. A. (2020). DetEdit: A graphical user interface for annotating and editing events detected in long-term acoustic monitoring data. <em>PLOS Computational Biology</em>, <em>16</em>(1). https://doi.org/10.1371/journal.pcbi.1007598 Wiggins, S. M., & Hildebrand, J. A. (2007). High-frequency acoustic recording package (harp) for broad-band, long-term Marine Mammal Monitoring. <em>2007 Symposium on Underwater Technology and Workshop on Scientific Use of Submarine Cables and Related Technologies</em>. https://doi.org/10.1109/ut.2007.370760 
description: # Ziphius cavirostris presence relative to vertical and temporal
 variability of oceanographic conditions in the southern california bight
 [https://doi.org/10.5061/dryad.8gtht76w1](https://doi.org/10.5061/dryad.8gtht76w1) **Dates of Collection: July 2007-September 2020 (H), January 2009-September 2020 (N)** **Geographic Location of Data Collection:** | **Site** | **Latitude** | **Longitude** | **Depth (m)** | | :------- | :--------------- | :---------------- | :------------ | | **H** | **32° 50.76’N**  | **119° 10.57’ W** | **1000** | | **N** | **32° 22.21’ N** | **118° 33.85’ W** | **1300** | ## Description of the data and file structure **File List:** 1. SiteH_Zc_monthly_bin.csv 2. SiteN_Zc_monthly_bin.csv This study used passive acoustic monitoring to study goose-beaked whale presence at two sites within the Southern California Bight; sites H and N. Each site has a separate csv file that includes the monthly bins, minutes of presence without percent effort accounted for, the percent effort, and the minutes of presence adjusted for percent effort. The first column, “bin”, indicates the month and year of the monthly bins. Goose-beaked whale presence, not accounting for percent effort, is given in minutes per month, indicated by “Zc_pres”. Percent effort can be found in the column “perc_eff”. Total monthly minutes of goose-beaked whale presence, adjusted for percent effort, is in the final column, “Zc_pres_eff_adj”. Times of “NaN” presence indicate periods of no effort.