Abstract:

Passive acoustic monitoring from autonomous surface vehicles was conducted from 2017-06-08 to 2017-06-17 as part of the 2017 LADC-GEMM (Littoral Acoustic Demonstration Center - Gulf Ecological Monitoring and Modeling) Gulf of Mexico Experiment (R/V Pelican PE17-23). A two-element hydrophone array was towed behind the autonomous surface vehicle (ASV). Raw data were collected at 500 kHz, in 16-bit WAV-format files. Concurrent CTD and GPS data were collected by the ASV during acoustic surveys. The dataset consists of a dataset file inventory, Automatic Identification System (AIS) data recorded from the R/V Pelican, GPS data from the towed hydrophone vehicle and the R/V Pelican, a listing of the depth of the hydrophones on the towed array, calibration data for the towed hydrophone array, the acoustic recordings, recording metadata, a listing of pertinent time/position/measurement rate information for each recording, a PDF description of the project design, and ArcGIS and QGIS files for preparing the planned survey map. The data are organized in directories by data type, with an accompanying descriptive document indicating parameters and units.

Suggested Citation:

Pierpoint, Chris and Lorenzo Scala. 2022. Autonomous surface vehicle-towed passive acoustic data collected during R/V Pelican cruise PE17-23 in the northern Gulf of Mexico from 2017-06-08 to 2017-06-17. Distributed by: GRIIDC, Harte Research Institute, Texas A&M University–Corpus Christi. doi:10.7266/N7154FDQ

Purpose:

Passive acoustic data were collected to localize marine mammal species including dolphins, sperm whales, and beaked whales. These data will be used to estimate population sizes and compare detection platforms with the glider and Environmental Acoustic Recording System (EARS) buoys acoustic datasets.

Data Parameters and Units:

The main parameters included are - Number of channels, sample rate (Hz), sample size (bits), voltage (volts), bit depth, latitude (decimal degrees), longitude (decimal degrees), heading (degrees true), speed (knots), time (UTC). Other detailed data parameters are described in a ReadMe file in the directory containing each type of data.

Methods:

The ASV C-Worker (CW76) was towed to the survey site by the R/V Pelican. Two hydrophones were towed 200 m behind the CW76 at 5 knots. Complete details are described in the document 'LADC_GEMM USV Towed Hydrophone System_2017.pdf.' Errata: The instrument time was synchronized with UTC. The hydrophone data file contains two columns for an additional sensor that was not used; these columns were left empty. The AIS and hydrophone data contain an empty column "UpdateOf" which was not used and left empty. The field "GPSIndex" in the AIS data table is keyed to an identically named variable in the GPS Data table. Unavailable times in the AIS data were set to 1970-01-01.

Instruments:

Hemisphere V102 GPS compass, National Instruments USB-6251 analogue-digital converter, Measurement Computing USB-1208LS (ADC for array depth).

Individual Files: